Cambrain stratigraphy and trilobites Turkey

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Cambrian Stratigraphy and Trilobites of the Samur DaArea, South of Hakkri, Southeastern Turkey

WILLIAM T. DEAN

Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, U.K.(E-mail: [email protected])

Abstract: Carbonates of the higher Koruk Formation at Yayla Tepe, near the Samur Da in southeastern Turkeyand about 17 km north of the Iraq border, contain peri-Gondwanan Middle Cambrian trilobites typical of theMediterranean Subprovince; these comprise at least seven genera and include the easternmost records in the Nearand Middle East of Eccaparadoxidesand the biozonal genus Pardailhania. In the lower half of the succeeding,largely clastic Seydiflehir Formation, Upper Cambrian trilobites from six levels in decalcified limestone interbedsinclude four new species [Coosinoides parthianus, Elegantaspis? montis, Prochuangia turcica, Taishania bassifrons]in addition to Chuangia? sp. and Palaeadotes sp. Unlike underlying Middle Cambrian faunas both here andelsewhere in southern Turkey, the affinities of the Yayla Tepe Upper Cambrian trilobites lie particularly with thoseof, among others, the Kushanian, Changshanian and Fengshanian stages of north and northeast China.

Relationships of these and other Upper Cambrian faunas in Turkey and peri-Gondwanaland are reviewed.

Key Words: trilobites, Cambrian, biostratigraphy, Southeastern Turkey

Samur Da Blgesinin Kambriyen Stratigrafisi ve Trilobitleri,Hakkri Gneyi, Gneydou Trkiye

zet: Gneydou Trkiyede Irak snrndan 17 km kuzeyde Samur Da yaknlarnda yzeyleyen ve KorukFormasyonun en st kesimlerini oluflturan karbonatlar Akdeniz asprovensi iin tipik olan Gondwana evresi OrtaKambriyen tribolitlerini ierirler. Trilobitler en az alt cins ierirken, Yakn ve Orta Dou Eccaparadoxilerin en doukaytlar ile biyozonal cins olan Pardailhaniay kapsarlar. Bu birimleri zerleyen ve ounlukla klastik sedimanlardanoluflan Seydiflehir Formasyonunun en alt kesimlerinde yzeyleyen kirefltafl arakatklarnn alt farkl dzeyindenderlenen trilobitler Chuangia? sp. and Palaeadotessp. trlerinin yan sra drt yeni tr iermektedirler [Coosinoides parthianus, Elegantaspis? montis, Prochuangia turcica, Taishania bassifrons]. Gerek alflma alannda gerekseGneydou Trkiyenin dier blgelerinde yzeyleyen Orta Kambriyen faunasnn aksine, Yayla Tepe st Kambriyentrilobitleri kuzey ve kuzeydou indeki Kushanian, Changshanian and Fengshanian yafll kaya topluluklarndabulunan trilobitlerle benzerlikler sunarlar. Gerek bu alflma srasndan tanmlanan fosiller gerekse Trkiye veGondwana evresine ait dier st Kambriyen faunas arasndaki iliflkiler gzden geirildi.

Anahtar Szckler: trilobitler, Kambriyen, biyostratigrafi, Gneydou Trkiye

Turkish Journal of Earth Sciences(Turkish J. Earth Sci.),Vol. 15, 2006, pp. 225257. Copyright TBTAK

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Introduction

The southeasternmost corner of Turkey (Figure 1),bounded by the borders with Syria, Iraq and Iran, is amostly high, mountainous area which has long remained

isolated from the rest of Asia Minor and Mesopotamia. Aslong ago as the early Roman period access was almostimpossible, and remained unusually difficult relativelyrecently, as described in an account by Freya Stark(1959). In the eastern Taurus Mountains near the Samur[or Samora] Da, about 25 km SSW of the regionalcentre of Hakkri, Lower Palaeozoic rocks form twounequal inliers, elongated eastwest. They are traversed

from north to south by the valley of the River Zap[sometimes Upper or Great Zab], which runs fromHakkri into northern Iraq, eventually to join the RiverTigris south of Mosul, and exposes an extensive NSsection to the north of the small town of ukurca (Figure1). The area falls within the Border Folds, one of themajor structural units into which Turkey has been divided(Ketin 1966a; Gtnic et al. 1979; zgl 1984). LowerPalaeozoic strata were first recognised by Altnl (1963), who reported unnamed thick Cambrian (?) limestones,overlain by almost 1000 m of Giri Formation, comprisingSilurian (in fact, Cambrian and Ordovician) quartzites


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CAMBRIAN TRILOBITES OF SOUTHEASTERN TURKEY

226

with subsidiary limestones and siltstones; some of thelatter contained the trace fossil Cruziana and were

compared by Altnl with analogous rocks in northernIraq. The succession was reviewed briefly by Dean (1975,p. 365, Figure 2) who tentatively correlated thequartzites with corresponding Arenig strata in theSeydiflehir Formation of the Taurides. No Silurianoutcrops have yet been proved in this part of Turkey, butthe search for them continues.

The region south of Hakkri was subsequently re-mapped by geologists of the Turkish Petroleum

Corporation (T.P.A.O.), who demonstrated theimportance of the reference section at Yayla Tepe (2152m; Figure 1), about 2 km from the Samur Da and nearthe village of Ceylanl, in the mountains about 11 km eastof the Zap Valley. Field-work by the writer and OlivierMonod, with the logistical support of T.P.A.O. and itsgeologists, was undertaken in the summers of 1980 and1981; the results were summarised by Dean et al. (1981,

sss

s

IRAQ

Rive

r Zap

ANTICLINAL

AXIS

road

BORDER

NAFS

FOLDS

SYRIAIRAQ

U.I.S.SEABLACK

MEDITERRANEAN SEA

IRAN

PONTIDES

Derik

Yayla Tepe

TAURIDES

0 10 km

Mesozoic & Tertiaryformations (undifferentiated)

Upper Palaeozoicformations (undifferentiated)

?Zabuk Formation,?Lower Cambrian

ALLOCHTHONOUS UNITSTHRUST FROM THE NORTH

ukurca

Hakkari

Yayla Tepe

Kprl

Samur Da

N

road

MEASUREDSECTION

TuzGl

EAFS

LAKEVAN

0 200 km

HakkariHdai

Cal Tepe

Penbegli

-Tut

30 35 40 45

40

Koruk, Seydiflehir &Sort Tepe formations,Cambrian-Ordovician(undifferentiated)

Figure 1. Inset map of Turkey shows principal structural subdivisions of the country, after Ketin (1966a), Gtnic et al. (1979) and zgl(1984). The remainder of the figure is a simplified geological map of the mountainous area south of Hakkri, showing themeasured section on the east side of Yayla Tepe, based on T.P.A.O.s map (inDean et al. 1981; inJanvier et al. 1984). Age ofunits: ?Zabuk Formation = ?Lower Cambrian; Koruk, Seydiflehir and Sort Tepe formations [undifferentiated] = Middle Cambrianto upper Ordovician; Upper Palaeozoic formations [undifferentiated] = Ynl and Kprl formations (Devonian andCarboniferous) and Harbol Formation (Upper Permian carbonates); Mesozoic and Tertiary formations are undifferentiated butinclude Triassic marls, and Mesozoic and Eocene carbonates. EAFS= East Anatolian Fault System, NAFS= North Anatolian FaultSystem.


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W.T. DEAN

227

black limestone

and dolomite

member (part)

limestone

member

38.4m

formationand member bed and lithology trilobite distribution

fossillocality

grey and pink lime-stone and shale 3.2 m

thickly bedded,

grey limestone with

minor shale

interbeds 7.7 m

thickly bedded,

light-grey limestone

7.5 m

massive unit of

grey limestone 4.7 m

bioturbated

black micrite

estimated 38 m

grey limestone withsilty interbeds 1.8 m

red mudstone

with interbedded

nodular, grey lst.

and thin beds

brown siltstone

13.5 m

F

E

D

C

B

A

Z.68C

Z.69A

Z.69B

Z.70

Z.71B

Z.71A

Z.68BZ.68A

Yo.150

Peronopsissp.

Ecc

aparadoxidessp.

KORUKFO

RMATION(part)

Corynexochussp.

Derikaspissp.

Cono

.(Conocoryphe)sp.

Asturi

aspis?sp.

Genus

andspeciesundeterminedB

Genusandspeciesund

eterminedA

Pard

ailhaniahispida

transition beds at base of Seydiehir Formation (1.5 m)

5m

0

Figure 2. Measured section through the higher part of the Koruk Formation (Middle Cambrian) in the gorge along the southeastern side ofYayla Tepe, showing numbered fossil localities and vertical ranges of trilobites. Individual beds are indicated by capital letters A to Eso as to avoid confusion with the lower case letters a to i used for the Upper Cambrian portion of the Seydisehir Formation in Figures3 and 4.


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p. 276), and additional comments were furnished byDean & Monod (1997). Certain of the latter conclusionsare necessarily provisional, and further fieldwork at YaylaTepe and in the Zap Valley, undertaken with the help ofT.P.A.O. during summer 2004 had to be curtailed owingto security problems in the vicinity of the Iraq border.

Lithostratigraphy

The oldest Phanerozoic rocks in the Border Folds regionbelong to the Zabuk Formation, listed originally bySchmidt (1965) as Zabuk quartzite/sandstone formationand named for a village in the Derik-Mardin inliers, 300km west of the Zap Valley (Figure 1), where the unitrests unconformably on almost 500 m of andesites,spilites and tuffs with interbedded red sandstone andshale. The volcanic rocks (with base unexposed) were

termed Derik Volcanics by Kellogg (1960), and DerikFormation by Rigo de Righi & Cortesini (1964), whopostulated a thickness of more than 2000 m, and bySchmidt (1965). Ketin (1966b, p. 77) introduced a newname, Telbismi Formation, for the same rocks, but thishas since been abandoned (Dean 1982a), having beenused earlier (as Telbesmi Formation) by Kellogg (1960)for what is now the Sadan Formation. Positive evidenceof age is lacking, but the Derik Formation is generallyassigned, questionably, to the Precambrian because it isoverlain disconformably by basal sandstones of the ZabukFormation, said by Kellogg to be 584 m thick at the typesection, where they pass upwards into the KorukFormation without any discernible break. In the sides ofthe Zap Valley, outcrops of thickly bedded grey andbrown quartzite and sandstone, often with ripple marksand cross-bedding, are referred questionably to theZabuk Formation (Figure 1); the base is unexposed, butan intercalated limestone bed by the east side of the ZapValley yielded a single, specifically undeterminablefragment of Archaeocyathus, suggesting an EarlyCambrian age (Debrenne in Dean et al. 1981, p. 275).The Koruk Formation marks a change from clastic to

carbonate deposition that is mirrored in other parts ofsouthern Turkey. The name was introduced by Schmidt(1965) as Koruk Ls/Dol Fm and corresponds toKelloggs (1960) Sadan Dolomite, 243 m thick (seeDean 1982a for review of terms). At its type section,southeast of Derik, the succession is divisible into 228 mof thickly bedded dolomite, followed by 15 m of thinlybedded, grey and pink, sometimes nodular calcilutite,

with minor beds of calcarenite. This bipartite subdivisionis broadly applicable, although with minor, local variations in both lithology and age, along parts of theTaurides region. It is certainly appropriate for the ZapValley and Samur Da areas, where an estimated >300 mof thickly bedded, grey dolomite occur, in which nomacrofossils or microfossils were found. The term blacklimestone & dolomite member is used here (Figure 2) forthe lower part of the Koruk Formation, which ends witha 38 m (estimated) unit of thickly bedded, tough, blackbioturbated micrite that yielded a few fragments ofMiddle Cambrian trilobites; this unit represents alithofacies that is diachronous along the length of theTaurides and resembles parts of the black limestonemember which have been dated by means of trilobites aslate Early Cambrian at the al Tepe Formations typesection near Seydiflehir, 1000 km west of the Zap Valley

(Dean & Monod 1970; Dean 2005), and are overlainthere by basal Middle Cambrian light-grey carbonatescontaining the zonal species Acadoparadoxidesmureroensis.

The succeeding limestone member, 38.4 m thick asmeasured in the gorge section along the southeast side ofYayla Tepe, is divided (Figure 2) into six informal beds, Ato F; the lowest unit, Bed A, is thin (1.8 m of greylimstone with silty interbeds) and did not yield anymacrofossils, but most of the other units comprise thicklybedded, light- or medium-grey limestone and some (B, C

and E) contain trilobites which are generally difficult toextract. Bed E (3.2 m) marks a change to pink and greylimestone and calcilutite with subsidiary shale, lithologiesthat are essentially transitional to Bed F (13.5 m), whereinterbeds of grey nodular limestone and thin, brownsiltstone levels occur within conspicuous, often almostbrick-red mudstone from which no macrofossils ormicrofossils were obtained. The Koruk Formations typesection, near Derik, consists mostly of thickly ormassively bedded dolomite and quartzite, but the highest13.6 m (Dean et al. 1981, and authors observations)include thin (5 cm) limestone beds with regressively weathering interbeds of red and grey-green, rubblysiltstone which form an increasing proportion of the unit;no bright red mudstones and siltstones like those at theSamur Da were seen.

Although the Cambrian rock succession from theZabuk Formation to the top of the Koruk Formation inthe vicinity of the Zap valley can be broadly correlated


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with lithologies in the Derik-Mardin inliers, thesucceeding strata are lithologically distinct and coincide with an important change in palaeogeographicrelationships that is related to an episode of UpperCambrian marine transgression along the peri-Gondwanan margin. Southeast of Derik, the lowest partof the largely clastic type section, 1057 m thick, of theSosink Formation (Kellogg 1960; Dean 1982a)comprises 225 m of brown-weathering, grey silty shaleand siltstone with numerous thin (c. 56 cm) beds offossiliferous grey calcilutite and calcarenite which containa varied fauna of trilobites and inarticulate brachiopods asyet unknown from the remaining 832 m (estimated); thelatter are mainly brown-weathering, thickly bedded,often current-bedded siltstones and sandstones, poorlyfossiliferous but of late Middle and, in part, LateCambrian age, which form part of a postulated Sosink

Graben (Dean & Monod 1990, p. 341) and extendupwards to the unconformable base of the BedinanFormation (Ordovician, Caradoc Series).

Light-brown, fissile mudstones occur in the lower andmiddle Sosink Formation in its type area and are foundalso in the Penbeli-Tut inlier, about 500 km west of theZap Valley (Dean et al. 1997), where severalcharacteristic Koruk and Sosink trilobites are reported.By contrast, the Koruk Formation in the Zap Valley andparticularly along the conspicuous ridge of Yayla Tepe issucceeded by strata which not only differ lithologically

from those at Derik but also contain, in their lowest 970m (estimated), Late Cambrian faunas of Asiatic affinitiesas yet undescribed elsewhere in Turkey and distinct fromlatest Cambrian or earliest Ordovician genera from theSultan Da and al Tepe areas, in the western Taurides(see later). Corresponding strata have not been seen inthe Derik and Penbeli-Tut inliers, where late Middleand/or Late Cambrian clastics are overlain successively byLate Ordovician shales and Cretaceous carbonates.

Strata forming the lower half of the SeydiflehirFormation at Yayla Tepe become younger

northeastwards along the ridge-like hill and are dividedhere into nine successive informal units, a to i (Figures 3& 4). The Koruk/Seydiflehir formational boundarycoincides with the top of Bed F and forms a noteworthybedding-plane which descends into a small gully andmarks a change to more regressively weathering strata.Overlying the lowest part of the dip slope is a smallsection in 1.5 m of grey silty shale, interpreted as

transitional strata at the base of Unit a; the remainder ofthe latter consists largely of green-grey silty shale withsubsidiary thin layers of quartzite and sandstone, a few ofwhich comprise deeply weathered lenses of decalcified,sandy limestone. Most of the remainder of Yayla Tepe isoccupied by monotonous, brown-weathering, dark greyor green silty shales, but units b, c and d are sufficientlyarenaceous and resistant to form low ridges at thesouthwestern end of the hill. The northeastern end ofYayla Tepe is formed by a conspicuous, large bedding-plane at the top of Unit i which descends steeply to thebank of the stream in Ceylanl Deresi (Figure 3).Recognisable macrofossils are both rare and difficult toextract from the tough, grey micritic matrix, but theslightly undulating upper surface is marked by occasional weathered-out fragments of trilobites, assembled hereunder locality number Yo.162. From the valley of Ceylanl

Deresi the topography rises steeply northeast to thefeature formed by resistant, transgressive Devonian rocksof the Ynl Formation (Janvier et al. 1984). Theremaining 1100 m (estimated) of the SeydiflehirFormation are well exposed on the hillside and comprisedark, silty shales and thinly bedded sandstones. Theupper 500 m (estimated) yielded numerous examples ofCruziana, including the widespread ichnospecies C.furciferadOrbigny 1842, but no body fossils, and thesuccession resembles Arenig strata of the type SeydiflehirFormation in the central Taurides.

Age and Relationships of the Trilobites

Middle Cambrian

Middle Cambrian trilobites of Acado-Baltic (includingeastern Appalachian and Mediterranean) type extendfrom eastern North America through Central andsouthern Europe (France, Iberia, Bohemia) and acrossNorth Africa from Morocco at least to the basement rocksof the Qatara Depression in the Western Desert of Egypt(Andrawis et al. 1983). In southern Turkey they can betraced from the southwest of the country along theTaurides (including the Hdai and al Tepe areas) and theBorder Folds as far as Yayla Tepe.

All the genera recorded from the Koruk Formation at Yayla Tepe are typical of assemblages fround in theAcado-Baltic and Mediterranean subprovinces and most,including Peronopsis, Eccaparadoxides, ConocorypheandCorynexochus, have an extended vertical range within the

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Middle Cambrian. Exceptions are Pardailhania Thoral1947 and DerikaspisDean 1982a. The former, based ona French species, is index genus of the PardailhaniaBiozone; it is widespread from Iberia and southern

France, through Sardinia (Rasetti 1972) intosoutheastern Turkey, by way of the Taurides to theBorder Folds, where the Yayla Tepe material representsits, as yet, easternmost record. Shergold & Sdzuy (1984,p. 78), when discussing the evolution of solenopleuridgenera in what is now the Caesaraugustian, definedPardailhania as being distinguished from thestratigraphically preceding genus Badulesia by theappearance in the type (and biozonal) species P. hispidaof a single, transverse row of spines on the preglabellarfield, and this feature is clearly seen in specimens from

Bed B (Z.68A, Z.68C) at Yayla Tepe (Plate 1 (f), (g), (I),(k), (q)). Derikaspis, founded on material from strata inthe Derik-Mardin inliers now assigned to the topmostCaesaraugustian and Languedocian, occurs there withChelidonocephalusKing 1937; the latter genus, based onan Upper Cambrian type species fom Iran, is found also inthe Languedocian of southern France (Dean 1982a, pp.28, 35; Courtessole et al. 1988).

The oldest trilobites yet found in the Samur Da areaare rare Eccaparadoxidessp. and Conocoryphesp.; bothare specifically undeterminable but of Middle Cambrianage and occur here (Yo.150) in the topmost Koruk

Formation, in the highest part of a 38 m unit ofbioturbated black micrite. The lithology has not yet beenfound in the Koruk stratotype near Derik, but itresembles parts of the black limestone member of the alTepe Formations stratotype in the central Taurides (Dean& Monod 1970; Dean 2005) and represents yet anotherexample of the diachronous nature of some lithofacies inthe Lower and Middle Cambrian of southern Turkey. Theblack limestone at the al Tepe is of late Early Cambrianage, yields both ellipsocephalid and protolenid trilobites,and is overlain, apparently conformably, by the light-grey

limestone member, the lowest part of which contains thebiozonal species Acadoparadoxides mureroensis(see Dean2005). Both the Acado-Baltic and Mediterraneansubprovinces are characterised particularly by the varietyand abundance of Eccaparadoxides, Paradoxides andrelated genera, and the Samur Da represents their mosteasterly known occurrence in the Near and Middle East.They have not yet been recorded in adjacent parts of Iran,


230

NNESSW

YAYLA TEPE

2152m

KORUK

FORMATION (part)

a b ce

gd f

h i

Yo.159

Yo.162

Yo.157Yo.156

Yo.154Yo.160

& 160A

Z.73,

Yo.155

Z.72

YIINLIFORMATION

(Devonian)

0 500

metres

SEYDEHRFORMATION

(highest c.1100 m) :

dark-grey shale

and quartzites

with Cruziana

in upper half.

SEYDEHRFORMATION

(lowest 970 m)

STREAM

(Ceylanl Deresi)

Figure 3. Ascending SSWNNE cross-section along the crest and southeastern side of Yayla Tepe, showing position of trilobite-bearing localitiesin the lower half (Upper Cambrian) of the Seydiflehir Formation as listed in Figure 4 (after Dean et al. 1981, fig. 7).


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but certain genera (Abharella, Chelidonocephalus) fromthe higher Middle Cambrian and Upper Cambrian ofnorthern Iran are known from slightly lower levels(Pardailhaniaand Solenopleuropsisbiozones respectively)in the Penbeli-Tut and Derik-Mardin inliers,southeastern Turkey (Dean 1982a; Dean & Monod 1997;Dean et al. 1997). A record ofAbbarella[sic] sp. fromNiveau H (highest Middle Cambrian) of the MontagneNoire by Courtessole et al. (1988, p. 47, pl. 5, fig. 17) isconsidered doubtful.

The youngest Middle Cambrian trilobites at YaylaTepe occur in the upper part of Bed E, and neither of theadjacent beds D and F yielded macrofossils. Generainclude Peronopsis, which has a long range through mostof the Middle Cambrian in Sweden (Westergrd 1946, p.98), together with Derikaspis, mainly indicative of theCaesaraugustian and lower Languedocian. Corynexochus,

a very small, geographically widespread genus found asfar distant as the Idamean of Australia, is uncommon inBed E; it is recorded from the Jincella [Solenopleura]brachymetopaand Lejopyge laevigatabiozones [= highestMiddle Cambrian, and approximately upperLanguedocian] in Sweden, its type area (Westergrd1953). In southern Turkey the genus is particularlyabundant in red nodular limestones of the PardailhaniaBiozone at the al Tepe and Hadim, central Taurides(Dean 2005); in the Montagne Noire, southern France(Courtessole 1973, pp. 72, 75) closely similar examples

preserved in mudstone were recorded no higher than thePardailhania Biozone. The limestone member of theKoruk Formation at Yayla Tepe may not extend as high asthe top of the Caesaraugustian, and the possibility of astratigraphic hiatus at the Koruk-Seydiflehir formationalboundary cannot be excluded.

The Derik-Mardin inliers of the Border Folds (Figure1), although small in area, expose a large thickness ofCambrian rocks, including about 1060 m of mostly clasticsediments, the type Sosink Formation; these containtrilobites of late Caesaraugustian age (Solenopleuropsis)

at the base, followed by others interpreted as earliestLanguedocian within a thickness of 200 m (Dean 1982a).Succeeding strata yielded few macrofossils but beds withHolasaphus mesopotamicusDean 1972, estimated to beabout 450 m above the base of the type SosinkFormation, were originally assigned to the late MiddleCambrian; the latter age was later confirmed by means ofacritarchs (Martin inDean et al. 1997) for similar strata

and trilobites less than 10 metres (estimated) below theregional Cretaceous unconformity at Kaplandere, in thePenbeli-Tut inlier (Figure 1). This leaves the upper 560m of the type Sosink, now under investigation butprovisionally assigned to the Upper Cambrian; therelationship of these clastic to the lower SeydiflehirFormation of Yayla Tepe is not yet clear.

Upper Cambrian

Between the highest fossiliferous level in the KorukFormation (Bed E, Z.71B) at Yayla Tepe and the lowestfossiliferous sample in the Seydiflehir Formation (Unit a,Loc. Yo.154) are some 228.5 m of strata (13.5 m ofKoruk carbonates and 215 m of Seydiflehir clastics) inwhich no macrofossils or microfossils were found. Fromthis point upwards there is a marked change in the

affinities of the faunas, which are of Chinese and Iraniantype, rather than Mediterranean and Acado-Baltic.

The Upper Cambrian of China is conventionally dividedinto three stages, Kushanian, Changshanian andFengshanian in ascending order, names based oncorresponding Series introduced for North andNortheast China by Sun (1923, 1924). These weresubsequently employed by Kobayashi (1933) and by Sun(1935, tables A, B), whose sequence, after due allowancefor changes in faunal nomenclature, differs remarkablylittle from later compilations such as those by Lu & Dong

(1953, p. 183, based on a revision of type sections inShandong), Zhang Meisheng (1989, pp. 127130), ZhuZhaoling & Wittke (1989), Peng (1992, p. 10), Chang &Jell (1987, p. 33) and Shergold in Kaesler (1997, p.309). Sun considered his Kushanian or DrepanuraZoneto be Middle Cambrian, and the remainder of his originalsequence is as follows: Changshanian Stage, C1 Chuangiabatiaor ChuangiaZone, C2 Changshania conicaZone, C3Kaolishania pustulosa Zone; Fengshanian Stage: F1Ptychaspis subglobosa Zone, F2 Sinosaukia pustulosaZone, F3 Quadraticephalus walcotti & Saukia acamusZone. The present zonal table (Figure 5) offers essentiallya compromise between the interpretations of variousauthors, none of which differ significantly, and thefollowing discussion is arranged in ascending stratigraphicorder of stages and zones.

Kushanian Faunas. The stratotype is at Kushan [=Hushan] in Shandong [= Shantung] Province where,

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according to Peng (1992, p. 9), The base is generallydefined by appearance ofBlackwelderia, and the Stage ischaracterised by by the Damesellidae, Monkaspis andLiostracina. As noted earlier, the assemblage ofProchuangia and Palaeadotes (determined originally asBergeronites) from Niveau I in the Montagne Nore wassaid by Chang (1996) to be of Kushanian age, and on thiscriterion the association of rare Palaeadotes withabundantElegantaspis? and Prochuangiaat Z.73 could beconsidered as Kushanian. The level is about 75 m higherthan a single record (at Yo.154; Figure 4) of a fewspecimens referred questionably to Chuangia?; ifcorrectly assigned, the latter may represent a genus that was redescribed by Chang & Jell (1987, p. 199) andrecorded by them only from the ChuangiaBiozone of thelowest Changshanian, that is to say from post-Kushanianstrata.

Changshanian Faunas. At the stages stratotype, in HebeiProvince (Peng 1992, p. 9), the base is drawn at theappearance of Chuangia and Luotuolingia; Damesellidaedisappear and are replaced by Changshaniidae andKaolishaniidae. In the Elburz Mountains of Iran, Kushan(1973, pp. 125128, Tables 2, 3) employed successivezones of Drepanura, Prochuangia, Kaolishania andAlborsella for the Upper Cambrian; he assigned theoverlying Saukia Zone to the Tremadoc (basalOrdovician), as did Wolfart (1970), but the nominal

trilobite is now re-assigned to Mictosaukia(see later) andthe zone is better considered as highest Upper Cambrian.

Chuangia Zone. The occurrence of rare, poorly preservedChuangia? sp. at Yo.154 (see above) in the upper third ofUnit a represents the only record of the index leiostegiidfrom Turkey, and further material is required. Althoughthe level pre-dates the lowest evidence of Palaeadotes,Elegantaspis? and Prochuangiaat Yayla Tepe, it should benoted that in North China Lu & Qian (1983, pp.248249) divided the ChuangiaZine into two parts: an

upper, or B, Chuangia subquadrangulataSubzone, withseveral subspecies of Chuangiaor its subgenera; and alower, or A, Prochuangia mansuyiSubzone, with speciesof, among others, Paracoosia, Prochuangia andPseudagnostus. The same authors noted thatProchuangia is usually associated with Chuangia, butmore frequently very abundant below the beds containingChuangia. The stratigraphic position of the two genera

was correlated by Lu & Qian (1983, p. 249) withapproximately the upper half of the Olenus Zone inSweden (Westergrd 1947) and the westerly extensionof the Prochuangia-Chuangiafaunas from China throughthe Middle East to the western Mediterranean was noted.For present purposes the base of the Changshanian atYayla Tepe is provisionally drawn at Z.73.

Changshania Zone. Presence not confirmed.

Maladioidella Zone. No evidence for the zone has so farbeen found at Yayla Tepe and the unit was omitted byZhou & Yuan (1982, p. 294) from their zonal table forNorth and Northeast China, although it was retained byZhang (1989). In the Sultan Da area of the westernTaurides (Figure 1), some 1100 km west of Samur Da,

the index genus was reported (as Maladioidella kelteri) byShergold & Sdzuy (1984, p. 88), who also reillustratedsame type material of the type species, M. splendensEndo inResser & Endo 1937, from Liaoning Province,northeast China; they attributed to the genus an ageapproximating to the OlenusBiozone of Scandinavia andthe Welsh Basin. If M. kelteri is correctly assigned toMaladioidella, the relevant Sultan Da fauna mayrepresent a Changshanian level that either is youngerthan any of the assemblages at Yayla Tepe, or is not yetrecognised there. The genus may occur in Iran, where

Saratogia latefronsKing (1937, p. 10, pl. 2, figs. 3a-c),from Imam Sayad Hassan, west of Isfahan, was referredto Maladioidellaby Wolfart & Krsten (1974, p. 218).The eponymous genus of the KaolishaniaZone, based onK. pustulosaSun (1924, p. 53) from the Changshanian ofShandong (see also Chang & Jell 1987, p. 224), has notso far been found at Yayla Tepe but was recorded, asMaloidella [sic], from the Upper Cambrian of Oman(Fortey 1994, p. 43). Kushan listed Kaolishania,Chuangiaand Prochuangiafrom a 52 m unit of dark-greylimestone in the Elburz Mountains of northern Iran, butWittke (1984, p. 99) claimed thatKaolishaniadoes not

occur there and referred Kushans material to a newsubgenus K. (Eokaolishania). Taishania bassifrons, fromYo.157 in the lowest part of unit e at Yayla Tepe, occursthere with Prochuangiaand reprsents a genus whose typespecies, T. taianensis Sun (1935, p. 68, pl. 3, figs.2025), is recorded only from the KaolishaniaZone (seealso Chang & Jell 1987, p. 244, pl. 120, figs. 512).


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W.T. DEAN

233

?

?

UNIT &

LITHOLOGYTRILOBITE OCCURRENCE

ORDOVICIAN

FOSSIL

LOCALITYFORM-

ATION

KORUK

FM.(part)

BIOZONE

Micto-

saukia

Kao

li-

shania

Alborse

lla

?

CHANGSHANIAN

KUSHANIAN

FENGSHANIAN

CAM

BRIAN(part)

UPPE

RCAMBRIAN

STAGE

SERIES

SYSTEM

thinly bedded sandstonewith dolomitic grey

limestone at top 54 m

green-grey,silty shale 40 m

green-grey shalewith beds quartzite,some ripple-marked

202 m

green-grey shalewith occasional

beds sandstone andsandy limestone 102 m

green-grey, silty shale;thinly bedded sandstoneand sandy limestone in

lowest part 108 m

green-grey, siltyshale with thin bedsbrown-weathering

quartzite 270 m

1.5 m transitionbeds at base

thickly bedded, greycarbonates

thinly bedded sandstonewith occasional bedssandy limestone 80 m

silty shale passinginto thinly bedded

sandstone andsandy limestone 67 m

grey, silty shalewith sandy limestone

at base 47 m

Yo.162

Yo.160

Yo.160A

Yo.159

Yo.157

Yo.156

Yo.154

Yo.155Z.73

Z.72

Chuangia?sp.

Elegantaspis?montis

Palaeadotessp.

Olenid?undetermined

?Micragnostussp.

nozonal

evidence

Niobella?sp.

Mictosaukia

.M.rotun

data

cf

Prochuangiaturcica

Pagodia(Wittekindtia)

variabi

lis

Taishania

bassi

frons

Coosinoidespart

hianus

Alborse

llastoeck

lini

Damesellacean?

undetermined.

0

90

metres

i

b

a

g

c

d

e

f

h

SE

YDEHR

FORMATION

(lowest970m)

Figure 4. Stratigraphic column for the lower half (Upper Cambrian) of the Seydiflehir Formation at Yayla Tepe, showing vertical rangesof trilobites and levels of fossil localities in relation to units a to i. Locality Z.85, listed in the text and positioned on the east sideof the Zap Valley, 10.7 km west-northwest of Yayla Tepe, is estimated to be at the same level as Locality Z.73.


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234

Scandinavia&

Welsh

Basin

Ac

erocare

Mediterranean

region,

Iberia&Tu

rkey

North&Northeast

China

BaseofTremadocSeries

Nostages

orbiozones

establis

hed

nobiozones

esta

blished

unconformable

Cretaceous

limestones

Nosatisfactory

zonation

Leonian

UPPERCAMBRIA IDDLECAMBRIAN

P

eltura

Jincella

brac

hymetopa

Goniagnostusnathorsti

Ptychagno

stuspunctuosus

Lejopyge

laevigata

Trip

lagnostusgi

bbus

Eccap

aradoxides

in

sularis

Acadoparadoxidespinus

Acado-paradoxidesoelandicus

Paradoxidesforch-hammeri

Paradoxidesparadoxissimus

Ptychagno

stuspraecurrens

Lep

toplastus

Agnostuspisi

formis

Par

dailhania

Badulesia

Solenopleuropsis(s.s.)

Parabo

linaspinulosa

Olenus

Homagnostus

o

besus

Aca

dopara

doxi

des

mureroensis

Aci

dusus

atavus

Hypagnos

tus

parvifrons

Tomagnostus

fissus

&

&

upper

middle

lower

CaesaraugustianLanguedocian

Fengshanian Changshanian Kushan-ian

Derik-Mardin

inliers

Sam

urDa&

Za

pValley

BorderFolds

Yaojiayuel

la

Shantungaspis

Koc

haspis

Crepicephalina

Amphoton

Taitzu

ia-P

oshania

Leiopeishania

Damesel

la-Y

abeia

Blackwel

deria

Drepanura

Chuangia

Changshania

Maladioidel

la

Kao

lishania

Qua

draticep

halus

Mictosaukia

orientalis

Ptychaspis-

Tsinania

Bai

liel

la-L

ioparia

Changian

KorukFm.(part)

KorukFm.(part)

SosinkFm.

Hsuchu-angian

Maochu-angian

?

* ** ** * * * **SeydiehirFm.(lowerhalf)

Figure

5.

TableshowingcorrelationoftheKorukFormationandlowerS

eydiflehirFormationatYaylaTepeandintheB

orderFoldsofTurkeywithMiddleandUpperCambrianbiozones

andstagesinBa

lto-Scandia,

theMediterraneanregion,andNo

rthandNortheastChina.

Asterisksindicateap

proximatepositionsoffossiliferouslevelsatY

aylaTepe.


11/33

Fengshanian and Younger Faunas. At the stratotype, inHebei Province, northeastern China (Peng 1992, p. 9),the base of the stage is drawn at the appearance ofsaukiid trilobites and Tsinania, whilst the top is markedby the entry of conodonts that pre-date the appearanceof Rhabdinopora flabelliformis subspecies. Shergold(1991, p. 23) included within Mictosaukiaa large numberof geographically widespread species but excluded somethat he had earlier (Shergold 1975) assigned to thegenus, which he said was restricted to a relatively narrowinterval at the close of the Late Cambrian, correspondingpresumably to the Mictosaukia orientalisZone of earlierworkers. He assigned to the genus both Saukia rotundataKushan (1973, p. 157) from northern Iran, and S.cf.rotundata from Yayla Tepe, Yo.160 described by Dean(1982b, p. 91). Also included in Mictosaukiaby Shergoldwere Saukia wirtzi Wolfart (1970, p. 43) and Saukia

turgidaWolfart (1970, p. 47), both of which came fromstrata in Afghanistan assigned by Wolfart to theTremadoc but now interpreted as highest UpperCambrian.

The lower limit of the Fengshanian at Yayla Tepe isdrawn provisionally here at the base of Unit f, 47 m ofgrey, silty shale with a thin basal bed of decalcifiedlimestone (Yo. 159) which yielded the ptychaspididgenius Alborsella Kushan(1973, p. 153), proposed by itsauthor as index for the highest part of the UpperCambrian as interpreted by him. An AlborsellaZone has

not been recognised in the Chinese Upper Cambrian, butthe term was retained by Wittke (1984, p. 97) for theElburz succession and is applied here to an undeterminedthickness of largely silty shale and quartzite beds above Yo.159. The stratigraphic value of the associatedcrepicephalid Coosinoides parthianus sp. nov. is not yetevident but the type species, C. elegantulusIvshin 1962,came from the Kuyandinian Stage of Kazakhstan, whichcorresponds approximately to the type Changshanian. Anassociated, undetermined olenid? at Yo.159 adds noreliable evidence of age, but certain features (see laterdiscussion) recall highest Upper Cambrian genera fromScandinavia reviewed by Westergrd (1922) and byHenningsmoen (1957; inMoore 1959).

Material from Yo.160, in the lowest part of Unit h atYayla Tepe, is now assigned to the highest Fengshanian(Upper Cambrian) rather than to the lower Tremadoc.The meagre sample includes also an incomplete,compressed asaphid cranidium and pygidium illustrated

by Dean (1982b, pl. 1, figs 12, 16) as Niobella? sp., agenus first described from the Tremadoc of Wales butfound also in the higher upper Upper Cambrian. A broadlysimilar form from the Sultan Da, western Taurides, wasassigned by Shergold & Sdzuy (1984, p. 106) to Niobellacf.primaeva(Westergrd 1909; see also Henningsmoen1958), a latest Cambrian (Acerocare Zone) species inSweden and Norway. The Sultan Da trilobite is one of anassemblage (including apecies of Proteuloma,Koldinioidia, Onchonotellus, Macropygeand Parakoldinia)that is widespread in southern Turkey and wasconsidered as initial Tremadocian by Shergold & Sdzuy, who reviewed its distribution in a belt extending fromMexico (Robison & Pantoja-Alors 1968) to China andKorea. More recently Loi et al. (1996) re-interpretedthese Sultan Da faunas and related assemblages inSardinia as highest Upper Cambrian, associated with a

widespread marine regression in the AcerocareZone (theAcerocare Regressive Event of Erdtmann 1986) andfollowed by marine transgression that accompanied anincrease in distribution of the graptoloid Rhabdinoporaflabelliformis.

For some years it has become increasingly clear thatseveral trilobites previously considered indicative of theTremadoc appeared earlier, whilst certain genera andeven species may cross the Cambrian/Ordovicianboundary as defined by the incoming ofR. flabelliformis.For example, Proteuloma cf. geinitzi (Barrande 1868),

recorded from the Sultan Da, western Taurides, byShergold & Sdzuy (1984) refers to a species from theLower Tremadoc of Bavaria that is recorded from thesame level in the type Tremadoc area of North Wales(Rushton 1982, p. 550), where the genus, together withother Tremadoc forms occurs below the firstappearance of R. flabelliformis. In Hunan Province,southeast China, Peng (1992, pp. 10, 14) describedProteulomafrom strata correlated with the highest partof the Acerocare Zone. Macropyge Stubblefield inStubblefield & Bulman (1927), based on a British LowerTremadoc type species, occurs in both the central andwestern Taurides, where its age was postulated as earlyTremadocian (zgl et al. 1973; Shergold & Sdzuy1984), but the genus occurs in the Upper Cambrian ofChina (Peng 1992, p. 41). Relevant strata of southernand southeastern Turkey have not yet yielded dendroidgraptolites and the rarity of limestone beds suitable foretching limits the use of conodonts.

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The youngest trilobites collected at Yayla Tepe areleiostegiids from Yo.162, assigned by Dean (1982b, p.91, pl. 1, figs. 16) to Pagodia(Wittekindtia) variabilisWolfart 1970. The species was first described from thesupposed Lower Tremadoc of Surkh Bum, centralAfghanistan, and founded on type material from twolocalities which yielded, among others, Harpides andMacropyge (both widespread in the Tremadoc), anasaphid Hazarania, an acrocephalitid Afghancephalites, apilekiid, and the two Saukiaspecies noted above, now putin Mictosaukia and considered as highest UpperCambrian. In northeastern Spain, Pagodia(Wittekindtia)alarbaensis Shergold & Sdzuy (1991, p. 214) closelyresembles the corresponding Yayla Tepe material.

The Upper Cambrian/Ordovician boundary at Ferrals-les-Montagnes, in southern France, is imprecisely defined,and coincides in Courtessole et al.s (1988, fig. 18)

section with a trilobite-free interval of 461 m whichseparates the upper limit of Bergeronites [nowPalaeadotes] and Prochuangia from the appearance ofEuloma (s.l.). Onchonotellus (s.l.) in the supposedTremadoc; in other words from genera corresponding tothose in the western and central Taurides that couldequally well be considered indicative of the UpperCambrian. Assemblages like those at the Sultan Da areknown also from impersistent pink and grey limestonebeds within clastics of the Seydiflehir Formation in the alTepe area, central Taurides (Dean & Monod 1970; and in

Dean 2005, p. 19). Samples are smaller and less variedthan those from the Sultan Da, but Micragnostus?,Niobella? and, especially, Proteuloma cf. geinitzi arecommon to both areas. No graptoloids have been foundin the adjacent silty clastics and the possible Fengshanianage of the trilobites remains unconfirmed. No comparablefaunas are yet known from the Yayla Tepe area, wherethe oldest Ordovician fossils are abundant examples ofCruziana furciferadOrbigny 1842 on the mountain-sidenortheast of Ceylanl Deresi (Figure 3). Selley (1976, p.205) commented on the occurrence of the Cruzianaichnofacies in subtidal and shallow marine environments,and also noted records of the index genus from bothpost-Palaeozoic strata and fluvial formations, in whichtrilobites should not occur; such claims suggest thatinterpretation ofCruzianaas the work of a trilobite is stillequivocal or unlikely, as was postulated by Whittington(1980, pp. 202203). In the Taurides Cruziana furciferais widespread, sometimes dated as lower Arenig by

means of body fossils from adjacent strata, but not inassociation with them. It has been suggested (referencesin Shergold & Sdzuy 1991, p. 201) thatC. furciferamaygrade into certain other species in Celtiberia, some ofthem as old as Upper Cambrian, but such evidence hasnot yet been published for Turkey.

Systematic Palaeontology

Terms are essentially those used in Volume O, Arthropoda1, of the Treatise on Invertebrate Palaeontology(Harrington et al. in Moore 1959, p. O124) withemendations proposed by Whittington & Kelly (inKaesler1997) for the second edition of that work. Figuredspecimens housed in the National Museum of Wales,Cardiff, carry numbers with the prefix NMW.95.34G;other material is in Maden Tetkik ve Arama (M.T.A.)

Genel Mdrl, Ankara. The number of specimensfound at each locality is indicated in the text as follows:rare (14); moderately common (510); abundant(1120); very abundant (> 20). All specimens are fromthe Koruk Formation and Seydiflehir Formation at theYayla Tepe section (Figures 3 & 4).

Trilobites from the Koruk Formation

Family Peronopsidae Westergrd 1936

Genus PeronopsisHawle & Corda 1847

Type Species. Battus integer Beyrich 1845, from theMiddle Cambrian of Bohemia.

Peronopsissp.

Plate 1 (v)

Figured Specimen. Cephalon, NMW.95.34G.531, localityZ.71A. Unfigured cephalon, NMW.95.34G.532, is fromZ.71A, and two further cephala, NMW.95.34G.537 and538, are from Z.71B. Both localities are in Bed E (rare).

Discussion. No detailed comparison is made, but there isa general resemblance to the cephalon of the neotype ofPeronopsis integra(Beyrich), illustrated by Snajdr (1958,pl. 3, fig. 2), although the latter species has a slightly wider (sag.) cephalic border. The Swedish speciesPeronopsis fallax (Linnarsson 1869), together with various subspecies, was redescribed by Westergrd


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(1946, p. 37, pl. 2, figs. 1824); all show some variationin the relative length of the preglabellar field, andcomparison here may be made with Westergrds pl. 2,figs 20a, b, rather than with Linnarssons syntypes.Similar comments apply to Peronopsis fallax sallesi(Munier-Chalmas & Bergeron inBergeron 1889), fromsouthern France (Courtessole 1973, p. 116, pl. 2, figs.514) and illustrated from Spain by Sdzuy (1961, pl. 2,figs. 18).

Family Corynexochidae Angelin 1854

Genus CorynexochusAngelin 1854

Type Species. Corynexochus spinulosus Angelin 1854,from the Middle Cambrian of Sweden.

Corynexochussp.Plate 1 (r)

Figured Specimen. A cranidial fragment,NMW.95.34G.535, from Bed E, locality Z.71b, is the solerecorded example from Yayla Tepe of a genus that isparticularly abundant in Middle Cambrian(Caesaraugustian) carbonates of the al Tepe Formationin the Taurides, southern Turkey. The type species,redescribed by Westergrd (1948, p. 10, pl. 3, figs. 79)shows some variation in the axial furrows, from straightto very slightly curved, abaxially concave. The axial

furrows of the present specimens are still more curvedand the glabella is wider frontally. Closer comparison maybe made with C. delagei Miquel 1905, from southernFrance and redescribed by Courtessole (1973, p. 136). Inthe Taurides C. cf. delagei was recorded from the alTepe Formation of the Sultan Da by Shergold & Sdzuy(1984, p. 1984, p. 74, pl. 2, fig. 9), and broadly similarmaterial from the same formation is known from Hadim(Dean & zgl 1981) and the al Tepe stratotype (Dean2005).

Family Paradoxididae Hawle & Corda 1847Genus EccaparadoxidesSnajdr 1957

Type Species. Paradoxides pusillusBarrande 1846, fromthe Middle Cambrian of Bohemia.

Only fragmentary evidence of the genus was found atYayla Tepe, and none of the material proved specificallyidentifiable. The oldest examples were two fragments of

cranidium (NMW.95.34G.497 and 498) in black, micriticlimestone of the black limestone & dolomite member atlocality Yo.150 (Figure 2), 0.8 m below the base of thelimestone member. Rare, small fragments of cranidiumand librigenae were found in Bed B at localities Z.68A(NMW.95.34G.914 to 918), Z.68B (NMW.95.34G.497,

498, 502, 503) and Z.68C (NMW.95.34G.920 to 922),with a single example in the basal part of Bed C, at localityZ.69A.

Family Solenopleuridae Angelin 1854

Subfamily Solenopleuropsinae Thoral 1947

Genus PardailhaniaThoral 1947

Type Species. Solenopleura(?) hispidaThoral 1935, fromthe Middle Cambrian of southwestern France.

Pardailhania hispida(Thoral 1935)

Plate 1(f), (g), (i), (k), (q)

1935 Solenopleura(?) hispidaThoral, p. 57, pl. 3, figs.2a, b, 3.

1968 Pardailhania hispida(Thoral 1935), Sdzuy, p. 119,pl. 6, fig. 13.

1973 Pardailhania hispida Thoral 1945 [sic],Courtessole, p. 160, pl. 15, figs. 18; pl. 27, fig. 4.Includes synonymy.

1984 Pardailhania hispida (Thoral 1935), Shergold &Sdzuy, p. 77, pl. 1, fig. 4; pl. 2, figs. 12, 13.

Figured Specimens. Three cranidia, all from Bed B:NMW.95.34G.501 (Pl. 1 (g), (q)) from locality Z.68A;NMW.95.34G.517 (Pl. 1 (i), (k)) and 518 (Pl. 1 (f)) fromZ.68C. No other examples found.

Description & Discussion. This distinctive biozonal species

has been extensively illustrated and the Yayla Tepematerial agrees well with published descriptions. Thesingle transverse row of spine bases on the preglabellarfield, considered by Shergold & Sdzuy (1984, p. 78) ascharacteristic ofP. hispida, is clearly seen on the presentspecimens. Courtessoles (1973) generic descriptionnoted four transverse rows of glabellar tubercles butsome of his illustrations show a fifth row, and five rows

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of large tubercles were clearly illustrated by Sdzuy(1968, pl. 6, fig. 13).

Family Conocoryphidae Angelin 1854

Subfamily Conocoryphinae Angelin 1854

Genus ConocorypheHawle & Corda 1847

Type Species. Trilobites SulzeriSchlotheim 1823, fromthe Middle Cambrian of Bohemia.

Subgenus ConocorypheHawle & Corda 1847

Conocoryphe (Conocoryphe) sp.

Plate 1 (h), (m)-(o), (t), (u)

Figured Specimens. All cranidia, from Bed B.NMW.95.34G.499 (Pl. 1 (m)-(o)) from locality Z.68A;

NMW.95.34G.505 (Pl. 1 (u)) from Z.68B; andNMW.95.34G.512 (Pl. 1 (t)) and 513 (Pl. 1 (h)) fromZ.68C.

Other Material. NMW.95.34G.500 & 916 (Z.68A),NMW.95.34G.504, 506 to 508 (Z.68B), NMW.95.34G.514 to 516 (Z.68C), NMW.95.34G.916 (Yo.151). Rareat Z.68A; moderately common at Z.68B and Z.68C.

Description & Discussion. The present cranidia generally

resemble C. (Conocoryphe) brevifrons (Thoral 1946),from the highest Caesaraugustian of southern France andredescribed by Courtessole (1973, p. 186, pl. 19, figs.19). Differences include the longer (sag.), flat-toppedanterior border (seen in Plate 1 (h)), and the conspicuousanterior border furrow (Plate 1 (o)) of uncompressedTurkish specimens, in which the frontal area has medianlength 3135% that of the cranidium, compared with2530% in the French material. In southwestern TurkeyShergold & Sdzuy (1984, p. 84) reported C. (C.) cf.brevifronsfrom the SolenopleuropsisZone of the Sultan

Da. In the Montagne Noire the species was listed byCourtessole (1973) only from his Niveau F (topmostSolenopleuropsisZone), that is to say, at a horizon higherthan the Pardailhania Zone; the only Conocorypherecorded from the latter level in France is C.(Parabailiella) languedocensis. As noted by Shergold &Sdzuy (1984, p. 85), C. (Conocoryphe) differs basicallyfrom C. (Parabailiella) Thoral 1946 in having a facial

suture which remains entirely on the border. InParabailiella the suture typically cuts across the lateralborder furrow, but there is a gradation between the twoconditions. On this criterion the present Turkish cranidiaare better placed in C. (Conocoryphe), but even in a singlecranidium (for example, Plate 1 (t)) the left and rightsides may show slight differences in development.

?Family Ordosiidae Lu 1954

Genus DerikaspisDean 1982a

Type Species. Derikaspis toluni Dean 1982a, from theMiddle Cambrian of Derik, southeastern Turkey.

Derikaspissp.

Plate 1 (a) (e), (j)

Figured Specimens. NMW.95.34G.519 (Plate 1 (d), (e)),Z.69B; NMW.95.34G.521 (Plate 1 (a)), 523 (Plate 1 (c))and 529 (Plate 1 (b)), Z.70, both levels in the upper partof Bed C; NMW.95.34G.533 (Plate 1 (j)), from Z.71A,upper half of Bed E.

Other Material. NMW.95.34G.520, 522, 524, 527, 528,534, 540 & 541. Rare at Z.69B; moderately common atZ.70; rare at Z.71A & Z.71B.

Description & Discussion. The best preserved of threeincomplete cranidia (Plate 1 (d), (e)) differs from that ofthe type species (Dean 1982a; especially figs. 53a-c) inhaving: straighter axial furrows; a glabella moreuniformly covered with smaller tubercles except on the weakly defined L1-3; and a thicker, slightly narrower(sag.) anterior border and preglabellar field, the formercarrying at least one row of tubercles coarser than thoseon the glabella. Better comparison may be made withDerikaspis brianensis(Courtessole 1973; redescribed byCourtessole et al. 1988, p. 39) from southern France,

but both the French and Yayla Tepe specimens are slightlydistorted tectonically. A large left librigena (Plate 1 (a))closely resembles a paratype right librigena ofDerikaspistoluniDean (1982a, fig. 57) but carries a smaller numberof larger tubercles. A single fragment of pygidium (Plate1 (b)) shows the left pleural lobe with three and a halfpairs of ribs, and the remains of an ill defined, wideborder with shallow border furrow. Some comparison


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may be made with Turkish pygidia referred to ? D. toluni(see Dean 1982a, fig. 50) and ?Chelidonocephalusanatolicus(Dean 1982a, figs. 45a, b, 48, 49a-c), as wellas with pygidia of Chelidonocephalusfrom Iran (Wittke1984, pl. 3, figs. 2, 7, 11, 16, 17) and France(Courtessole et al. 1988, pl. 4, figs. 911).

Family Acrocephalitidae Hup 1953

Genus AsturiaspisSdzuy 1968

Type Species. Asturiaspis inopinatus [sic] Sdzuy 1968,from the Middle Cambrian of Spain.

Asturiaspis?sp.

Plate 1 (s)

Figured Specimen. A single cranidial fragment,NMW.95.34G.509, from Z.68B, in the highest part ofBed B.

Description & Discussion. The Turkish specimen, partiallybroken frontally, shares with the type species a tapered,sub-trapezoidal glabellar outline, a low eye ridge, a long(sag.), slightly upturned anterior border, and a broad(sag.) anterior border furrow that is slightly shallowermedially. The Spanish material described by Sdzuy (1968,p. 107, pl. 5, figs. 510) exhibits ontogenetic changes,

and smaller cranidia differ from the large holotype inhaving a proportionately shorter anterior border, shorterfrontal area, and wider (tr.) palpebral area. The Turkishcranidium has a relatively narrow (tr.) palpebral area andnarrow (sag.) preglabellar field but no detailedcomparison was possible. In Spain Asturiaspiswasrecorded by Sdzuy (1971, Table 1) from the lower partof the Middle Cambrian, corresponding to the LeonianStage.

Family Uncertain

Genus & Species Undetermined A

Plate 1 (p)

Description & Discussion. A single fragment of cranidium(NMW.95.34G.530) from Bed C, Z.70 has the glabellapartly exfoliated and shows granular ornamentation overmost of the surface, with traces of larger tuberclesarranged in three transverse zones which may

correspond to L1-3. Both the transversely straight SOand the surviving left axial furrow are deeply incised, andthe latter is crossed by a distinct eye ridge, directedposterolaterally. The form of the eye ridge and the tracesof an intermediate lobe between the postulated L1 and L2recall Derikaspisfrom the type area, but are insufficientfor certainty and do not match other specimens of thegenus from Yayla Tepe or Derik.

Genus & Species Undetermined B

Plate 1 (l)

Description & Discussion. Incomplete cranidium(NMW.95.34G.510) from Bed B, Z.68B, has anapparently almost smooth exoskeleton and the glabellaroutline is subparabolic, bounded by axial furrows whichshallow forwards around LA. SO is transversely straight

and very shallow, defining an LO whose median length(sag.) is less than one-fifth that of the cranidium. Large,smooth eye lobe sited opposite middle of the glabella, andequal to about one-third of its length. Anterior section ofthe left facial suture diverges at about 20 degrees fromthe sagittal line and then curves strongly inwards, wherea weakly defined, low anterior border occupies about halfthe anterior area. No satisfactory comparison has beenmade.

Trilobites from the Seydiflehir Formation

Family Elviniidae Kobayashi 1935

Subfamily Aphelaspidinae Palmer 1960

Genus ElegantaspisIvshin 1962

Type Species. By original designation, Elegantaspiselegantula Ivshin 1962, from the Upper Cambrian,Kuyandinian Stage, of central Kazakhstan. The genus wasassigned provisionally by Ivshin to the FamilyParabolinoididae Lochman 1956, but was latertransferred to the Aphelaspidinae by Shergold & Sdzuy(1991, p. 209), who provided a detailed discussion ofthis and other supposedly related genera. Ivshins (1962,pp. 81, 82) descriptions ofE. elegantulaand the closelysimilar E. betafrom the same horizon and area employedonly the cranidium and it is preferred here to useElegantaspis questionably for the Turkish material.Shergold & Sdzuys (1991, pp. 209211) account ofElegantaspis cf. beta from northeastern Spain was

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similarly restricted and the present description of theTurkish pygidium (Pl. 2 (h)-(j)) is based on an abundantassemblage composed almost solely of Elegantaspis?fragments, most of them cranidia, together with rareexamples of the distinctive genera Palaeadotes andProchuangia.

Elegantaspis? montissp. nov.

Plate 2 (a)-(c), (h)-(k), (l)?, (m), (n), (o)?, (u)

Derivation of Name. montis(Latin) = of the mountain, inthis case the Samur Da.

Diagnosis. Cranidium of aphelaspidine type, with lengthabout three-quarters the breadth; anterior marginbroadly rounded, and low frontal area divided into

subequal, flat anterior border and preglabellar field.Glabella subtrapezoidal, with bluntly rounded LA; externalsurface smooth, but internal mould occasionally (Plate 2(u)) shows almost indiscernible L1-3; SO transverse,shallow. Palpebral area about half breadth of adjacentglabella; palpebral lobe short (0.2 length of glabella),sited opposite L2, and linked to axial furrow by weak,curved eye ridge. Subelliptical pygidium has length twothirds the maximum breadth and its outline forms anunbroken, broadly rounded curve. Axis narrow, gentlytapered, with at least five rings on anterior half; tipmerges with broad (tr.), shallow, concave, unfurrowed

border; at least six almost smooth ribs are present,separated by well defined pleural furrows.

Type Material. Holotype, NMW.95.34G.148 (Plate 2(n)), Z.73; figured paratypes, NMW.95.34G.149 to 154and 156. Unfigured paratypes: NMW.95.34G. 157 to181, 1129 to 1136 (Z.70), 1137 to 1158 (Z.72) and1176 to 1187 (Z.73).

Horizons & Localities. All material is from the Yayla Tepesection, as follows: unit a, Z.72 (abundant); unit b, at asingle level with Z.73 (very abundant) and Yo.155(abundant). The species, found at only two levels about34 m apart, was easily the most abundant trilobite in theSeydiflehir Formation at Yayla Tepe.

Dimensions of Holotype Cranidium. Median length= 8.7mm, basal breadth= 11.7 mm (estimated), length of

glabella= 6.5 mm, basal breadth of glabella= 5.25 mm,distance across palpebral lobes= 9.25 mm, breadth (tr.)of frontal area= 8 mm.

Description. Cranidium of low convexity, with length

about 0.75 the basal breadth. Subtrapezoidal glabella asbroad as long, with straight sides converging at 3035to circumscribe rounded LA. Front of cranidium broadlycurved, and frontal area is divided into subequal halves byshallow anterior border furrow; preglabellar field is flatmedially, narrows (exs.) abaxially, where it merges withfixigenae and is bounded by anterior border with almostflat top and slightly bevelled posterior edge. LO, withweakly curved posterior margin, is defined by transverseSO that is shallow medially and almost indiscernible ataxial furrows. No lateral glabellar furrows visible on

external surface. Low palpebral lobe, with length about0.2 (estimated) that of glabella, is sited almost oppositeL2 and shows trace of palpebral furrow; breadth ofpalpebral area slightly less than half that of adjacent partof glabella. Anterior section of facial suture nearlystraight, slightly divergent to preglabellar furrow, whereit curves adaxially to margin; posterior section formssigmoidal curve to meet posterior border and margin sothat posterior field has breadth (tr.) about 0.75 that ofrear of glabella.

Pygidium semielliptical, with frontal breadth 1.6 thelength; anterior margin slightly curved, truncated bynarrow (exs.) articulating facets. Straight-sided axistapers at about 15, bounded by deep axial furrows;anterior half has five transversely straight axial rings,separated by faint ring furrows; posterior half indistinctlyfurrowed, ends in blunt tip that merges with posteriorarea. Pleural lobe plump, with six or seven flat-topped, well defined ribs, and declines to ill-defined concaveborder, where the pleural furrows become weaker andcurve posteriorly towards lateral margin; interpleuralfurrows faint.

Two associated hypostomes (Plate 2 (l) and (o)) fromZ.72 and Z.73 respectively, are assigned questionably tothe new species. Outline is subrectangular, narrowest(tr.) frontally, the posterior half widening to 0.75 themedian length. Middle body bounded by continuous rim-like border that is slightly wider medially. Anterior lobeoval, 0.75 the median length, bounded by shallow middlefurrow that dies out sagittally; posterior lobe crescentic in


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plan, ending opposite centre of hypostome. There is ageneral resemblance to an undetermined aphelaspidinehypostome from the Upper Cambrian of Antarcticafigured by Shergold & Cooper (1985, p. 104, fig. 7u),who suggested its possible assignment to the associatedApheloides? depressus Shergold & Cooper (1985, p.102); in any case it resembles the natant formrecognised by Fortey (1990).

Discussion. Photographs of the type material ofElegantaspis elegantulaIvshin (1962, pl. 5, figs. 57) areslightly modified and difficult to compare with Spanishcranidia assigned to the genus by Shergold & Sdzuy(1991, pl. 3). Ivshins (pl. 5, fig. 7) illustration of theholotype differs from our Turkish specimens in its morestrongly tapered glabellar outline and longer eye lobes; whether the anterior branches of the facial suture arestraight and sub-parallel, as in Ivshins line drawing (p.82, fig. 19) and one paratype (Ivshin 1962, pl. 5, fig.19), is questionable, and another paratype (Ivshin 1962,pl. 5, fig. 6) has the right anterior branch noticeablycurved.

FarsiaWolfart (1974, p. 116), from the Kushanian ofAfghanistan, was introduced questionably, andincorrectly, as a subgenus of Chelidonocephalus, thepygidium of which, as re-interpreted by Dean (1982a, p.31) and confirmed by Wittke (1984, p. 113), is differentfrom that of the type species Farsia abundans. The latter

(Wolfart 1974, pl. 19, figs. 59) shares withElegantaspis? montisa large, semicircular to semiellipticalpygidium, proportionately wider frontally, with slim,straight-sided axis and straight ring furrows. But thecranidium of the Iranian genus is easily distinguished by:its more tapered, trapezoidal glabellar outline, with deepSO and more distinct S1S3; wider (tr.) fixigenae; andthe longer (sag.) anterior area, inclined frontally to forma scoop-like structure (see Wolfart 1974, pl. 19, fig. 1).Cranidium, NMW.95.34G.155 (Plate 2 (p)-(r)), aninternal mould from Locality Z.72, superficially resemblesElegantaspis? montisin the form of the frontal area and

occipital ring. However, its glabella is more tapered andthe slightly curved axial furrows are abaxially convex withprominent muscle impressions in SO, S1 and S2. Narrowpalpebral lobes are sited opposite L2, and the anteriorbranches of the facial suture diverge more stronglyforwards than in E.? montis(about 55 degrees comparedwith about 30 degrees).

Family Leiostegiidae Bradley 1925

Genus ChuangiaWalcott 1911

Type Species. Ptychoparia? batiaWalcott 1905, from theUpper Cambrian of Shandong [= Shantung], NortheastChina.

Chuangia? sp.

Plate 3 (e), (f). (i), (j), (o)?

Figured Specimens. NMW.95.34G.157 (Plate 3 (e)),NMW.95.34G.158 (Plate 3 (f)), NMW.95.34G.159(Plate 3 (i)) NMW.95.34G.160 (Plate 3 (j)); questionablyNMW.95.34G.161 (Plate 3 (o) ? ). All from Unit a, Yo.154, where moderately common. This is the onlylocality at Yayla Tepe from which the genus has beenrecorded, even questionably.

Description and Discussion. Numerous species andspecimens ofChuangia, including the lectotype of the typespecies, designated by Walcott (1906, pl. 15, fig. 3) wereprofusely illustrated by Chang & Jell (1987, pp.199200, pls. 8992, 124, 125 in part) and by Lu et al.(1965). No satisfactory comparison is made with any ofthese or with other species from the Upper Cambrian ofChina, and all but one of the Turkish pygidia are bothdeeply weathered and dorsally compressed. Theexception (Pl. 3 (j)), an incomplete, three-dimensional

specimen illustrated as a latex cast, is convex andsemielliptical in outline with length 0.6 the breadth; itssubcylindrical axis is very slightly tapered and relativelylarge, with frontal breadth 0.4 that of the pygidium;there are two distinct axial rings, traces of a further two,and each pleural region carries two pairs of broad (exsag)ribs in addition to the articulating half rib.

Genus ProchuangiaKobayashi 1935

Type Species. Prochuangia mansuyi Kobayashi 1935,

from the Upper Cambrian of South Korea.

Prochuangia turcicasp. nov.

Plate 3 (a)-(d), (g), (k)-(m), (p), ( r)

Derivation of Name. turcica(Latin) = Turkish.

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Diagnosis. Cranidium nearly 1.5 times wider than long;glabella almost transverse frontally, with stronglyunequal L1L3 separated by S1S3 visible only oninternal mould; deep SO flexes slightly forwards laterallyand at sagittal line; palpebral lobes opposite S1. Pygidiumhas median length (excluding spine) 0.4 (estimated) ofthe overall breadth; large, gently tapered axis includestwo well defined, straight axial rings, with a further threefaintly defined, and ends in a very small, blunt terminalpiece; conspicuous pair of marginal spines is splayedposteriorly, the large base of each spine being sitedopposite the rear 0.6 of the axis; marginal furrowdeepest on smaller specimens and merges with firstpleural furrows.

Type Material. Holotype pygidium, NMW.95.34G.162

(Plate 3 (m); Z.73). Paratypes: NMW.95.34G.163 (Plate3 (a); Z.73), NMW.95.34G.164 (Plate 3 (b)-(d); Z.73),NMW.95.34G.165 (Plate 3 (g); Yo. 157),NMW.95.34G.166 (Plate 3 (k), (p); Yo.157),NMW.95.34G.167 (Plate 3 (l); Z.73), NMW.95.34G.168(Plate 3 ( r); Yo. 157). At Yayla Tepe the species wasfound in the lowest part of Unit b (Z.73, abundant), andin the lowest part of Unit e (Yo.157, rare); questionablyin the upper half of Unit c (Yo.156, rare)

Description & Discussion. Cranidium moderately convex

both longitudinally and transversely, with sagittal lengthabout 0.8 the basal breadth. Glabellar outline sub-trapezoidal, slightly constricted at S2, with basal breadth0.6 of its median length; overall it tapers gently from SOto transversely subrectangular LA, bounded by lowanterior border with length (sag.) about 0.13 that ofglabella. External surface smooth but internal mouldshows unequal L13, with faint S13 marked by shallow,suboval muscle impressions. LO occupies 0.2 of theglabellar length and narrows (exs.) distally where itcurves forwards slightly and is bounded by sinuous SOthat is visible on both internal and external mould. Smallpalpebral lobe sited opposite S1 and L2, where width (tr.)of palpebral area is about 0.66 that of adjacent glabella;low, distinct, oblique eye ridges curve slightly frompalpebral lobes to meet axial furrows at or near S3 (Plate3 (a), (c), (d)).

Pygidium, excluding paired posterolateral spines, hassagittal length 0.4 of breadth; anterior margin

transversely straight; posterior margin gently curvedbetween pair of broadly splayed border spines. Axisoccupies about 0.3 of the overall frontal breadth, andends in rounded terminal piece at border furrow; it isbounded by deep axial furrows which are almost straight,with slight break at third ring furrow; up to five straightaxial rings in addition to the small articulating half-ring.Pleural region carries deep, broad (exs.) first pleuralfurrow which delimits anterior half-rib and facet; thefurrow deepens and widens abaxially where it coalesceswith shallower border furrow, traverses base of pairedborder spine, and deepens towards and behind terminalpiece. A second pleural furrow is very shallow, andinterpleural furrows are almost indiscernible. The pairedlarge border spines are slightly curved, distally convex,and all available specimens (Pl. 3 (g), (k), (r)) show thatthey become progressively less splayed posteriorly with

increase in size of the pygidiumThe pygidium (excluding border spines) of the new

species is distinguished from that ofProchuangia gallicaFeist & Courtessole (1984, p. 181, pl. 1, figs. 17) ofsimilar age in southern France, by its relatively shorterlength (0.4 versus 0.6 estimated of the overall breadth).In addition the marginal furrow is shorter and moredeeply incised, especially posteriorly, and the borderspines have a notably larger basal breadth (tr.). Accordingto Shergold et al. (1976, p. 278) Prochuangia lacks apygidial border furrow, but this structure is visible,

although broad and shallow, among the type material ofthe French species P. gallica(see above). Several Chinesepygidia illustrated as Kaolishania? quadriceps (Dames1883) by Schrank (1975, pl. 4, figs. 49) exhibitvariation in overall outline, median length and the formand location of the paired border spines; most are distinctfrom P. turcica, but the original of Schranks pl. 4, fig. 5resembles the latter species in its straight anteriormargin, the median length equal to 0.46 the overallbreadth, and the form and location of the paired spines.Damess species was later referred to Prochuangia byShergold et al. (1976, p. 277).

Prochuangia mansuyiwas illustrated by Lochman-Balk(inMoore 1959, p. O319, fig. 236, 1a, b) by means ofline-drawings. Photographs used in Lu et al.s laterdescription (1965, p. 414, pl. 78, figs. 1823) are notvery clear but suggest that the (?compressed) glabella hasstraighter sides than P. turcica, and that the pygidium isslightly shorter, with less convex posterior margin; the


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apparently posterolateral position of the large marginalspines is of questionable significance and, as suggested bythe Turkish specimens, may vary during ontogeny.

Family Pterocephaliidae Kobayashi 1935

Genus TaishaniaSun 1935

Type Species. Mansuyia taianensisSun 1924, from theUpper Cambrian (Changshanian, Kaolishania Zone) ofShandong [= Shantung], northeast China. In Table B ofSun (1935) the range of Taishania was misprinted asextending through the three zones of the Fengshanian,but elsewhere in the same paper (p. 69 and Table A) itwas given correctly as Kaolishania pustulosaZone, upperChangshanian.

Taishania bassifronssp. nov.Plate 3 (h), (s), (v)

Derivation of Name. bassifrons(Latin) = low front, fromthe low preglabellar area.

Diagnosis. Taishania species with relatively longpreglabellar area, one third the glabellar length anddivided into equal halves by broad (sag.), shallow anteriorborder furrow. Glabella unfurrowed (excluding SO),straight-sided, subrounded frontally, with shallow fossulaat either end of preglabellar furrow. Palpebral area of

fixigena very narrow (tr.), flanked by small, gently curvedpalpebral lobe; posterolateral projection transverselyelongated.

Type Material. Holotype cranidium, NMW.95.34G.169(Plate 3 (v)); paratype cranidia, NMW.95.34G.170 (Plate3 (h)), 171 and 172 (Plate 3(s)). All from Yo.157, in thelowest part of Unit e.

Dimensions of Holotype. Median length of cranidium= 6

mm; length of glabella= 3.9 mm; maximum breadth (tr.)of anterior area= 6.2 mm; median length (sag.) ofanterior border= 1.0 mm; basal breadth of cranidium= >9 mm (est.).

Description. Known only from the cranidium, which is oflow convexity with basal breadth twice the sagittal length.Trapezoidal glabellar outline has almost straight sides

which converge forwards at 30 to transversely straightanterior margin; preglabellar furrow slightly shallowermedially and narrower than the axial furrows. No lateralglabellar furrows visible, and transversely straight SO isshallower and wider (sag.) over its median third,becoming deeper distally. LO small, with median length

(sag.) about 0.2 that of glabella, and its narrow extremitymerges with posterolateral portion of L1. Weaklydefined, small palpebral lobe set slightly in front of centrewith reference to glabella; palpebral area very narrow,about 0.2 of adjacent breadth of glabella. Posterolateralprojection of fixigena distally elongated, its length (exs.)about 0.7 the breadth (tr.), and posterior section of facialsuture meets posterior margin of cephalon at about 40.

Discussion. Suns (1935, p. 68, pl. 3, figs. 2025)detailed description of Taishania taianensis illustrated

three cranidia, a left librigena and two pygidia from theTawenkou Formation (Changshanian Stage, KaolishaniapustulosaZone) of Taian, Shandong. Details are difficultto discern in the photographs, and a later illustration ofthe cranidium by Lu et al. (1965, p. 351, pl. 65, fig. 2)used only an incomplete specimen, but several exampleswere figured by Chang & Jell (1987, p. 244, pl. 120,figs. 512). On the basis of the latter, T. taianensisresembles Taishania bassifronsin the glabellar outline andnarrow (tr.) palpebral area, but the former species hasthe palpebral lobe set further forward, with its posterior

margin opposite the centre of the glabella; there is nopalpebral furrow in T. taianensis, and that apparentlypresent in the Turkish species is seen on the internalmould. The preglabellar area in both species is dividedinto subequal halves by a shallower anterior borderfurrow, but it is relatively longer in the new taxon(0.330.36 of glabellar length compared with 0.24). Thelength (sag.) of the anterior border is less than that of thepreglabellar field in the Chinese species, whereas they aresubequal in the Turkish form. The anterior sections of thefacial suture, not visible in Sun's illustrations, are seen tobe slightly divergent in Chang & Jell's account of T.taishanensis, as they are in T. bassifrons. Most of theabove comments apply to Taishania (Weishania)constricta Zhu & Wittke (1989, p. 216, pl. 10, figs.18), type species of the subgenus and from the UpperChangshanian of Hebei Province, north China. Differencesbetween T. (Taishania) and T. (Weishania) were said toinclude the latter's possession of shallow axial furrows,

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relatively long palpebral lobes, and a glabellar outlinethat is constricted medially, though the first two of thesecharacters appear less significant; both subgenera have asmall occipital node that is not preserved in the newspecies.

Taishania platyfronsShergold (1980, p. 56, pl. 19,figs. 510, text-fig. 27A), from western Queensland, wasplaced in a new subfamily Atratebiinae, Family Uncertain.It differs from Taishania taianensis in its relativelyshorter, less tapered glabella (0.66 the crandial length,compared with 0.75), the almost effaced SO anduniformly short (sag.) LO, and particularly in the smallanterior border, which forms only a low, narrow (sag.)rim. T. platyfrons came from the Peichiashania tertia -Prochuangia glabellaAssemblage Zone, shown as aboutlow/mid Changshanian in a table by Shergold (inKaesler1997, p. 309), where P. tertiais replaced byT. secunda.

Anomocare persicumKing (1930, pl. 17, figs. 3, 3a)was based on a single cephalon from a limestone block atKuh-i-Namak, in Iran and about 40 km from the coast ofthe Persian Gulf (King 1930, fig. 1). The specimen waslisted by Kobayashi (1962, p. 111) as Taishania persica,and figured under that name by Morris & Fortey (1985,pl. 2, fig. 9). Trilobites from the same locality (thoughnot necessarily from the same block of limestone) weredetermined as Kaolishania? sp. and Maladioidessp. nov.by Kobayashi (1935, p. 187; 1962, p. 112) and

illustrated as such by Morris & Fortey (1985, pl. 2, fig.4, and pl. 3, fig. 2).

Family Crepicephalidae Kobayashi 1935

Genus CoosinoidesIvshin 1962

Type Species. Coosinoides elegantulusIvshin 1962, fromthe Upper Cambrian (Kuyandinian Stage) of centralKazakhstan. Ivshin (1962, Table) correlated theKuyandinian with most of the Chuangia Zone plus theremainder of the Changshanian, up to the top of the

Kaolishania Zone (a Maladioidella Zone was not thenrecognised); that is to say, the Kuyandinian of Kazakhstancorresponded essentially to the Changshanian of NorthChina. C. elegantuluscame from the Seletinian horizonwith Irvingella, equated by Ivshin with the KaolishaniaZone and part of the underlying Irvingella - ChangshaniaZone.

Coosinoides parthianussp. nov.

Plate 2 (d)-(g)

Derivation of Name. parthianus(Latin), from the ancientkingdom of Parthia.

Diagnosis. Coosinoides species distinguished particularlyby the long (sag.) preglabellar area which is of lowconvexity, about 0.4 the cranidial length, and divided byshallow, incised preglabellar furrow into equally long(sag.) preglabellar field and anterior border. Curved SO ismarkedly convex forwards and becomes faint abaxially;anterior section of facial suture is strongly curvedforwards, and breadth (sag.) of anterior area is equal tothat across palpebral lobe.

Type Material. Holotype cranidium, NMW.95.34G.173(Plate 2 (e)-(g)); paratype cranidium, NMW.95.34G.174(Plate 2 (d)). Both are from the Seydiflehir Formation,lowest part of unit f, at Loc. Yo.159, Yayla Tepe. Rare.

Dimensions of Holotype. Median length of cranidium=9.5 mm; length of glabella= 5.8 mm; breadth (tr.) ofanterior area= 8 mm; breadth across palpebral lobes=7.6 mm (estimated); basal breadth of glabella= 4.3 mm;length (sag.) of anterior border= 2.2 mm.

Description & Discussion. Both the new species andCoosinoides elegantulus Ivshin (1962, p. 234, pl. 15,figs. 110) have a long, low, spatulate preglabellar area,but the latter occupies 0.3 (sag.) of the cranidial length inthe Russian species, compared with 0.4 in C. parthianus, which also has a less tapered glabella, more bluntedfrontally. Preglabellar area is divided into two unequal,transverse halves by gently arched, shallow furrow (?anterior border furrow); in C. parthianus the anteriorhalf is 1.5 times longer (sag.) than the posterior half,whereas in C. elegantulusthe corresponding figure maybe up to 3. In both species the palpebral area of the

fixigena is narrow (< 0.5 the adjacent breadth of theglabella), and the long palpebral lobe is rim-like, narrow, with distinct palpebral furrow. The occipital ring ofC.elegantulusis well defined, including distally, by a deep,almost transverse SO; but in the Turkish species SO isshallow and forms a curve, convex forwards, thatbecomes markedly shallower abaxially. Some of Ivshinstype specimens ofC. elegantulusdisplay angulation of the


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anterior section of the facial suture at its intersection withboth anterior border furrow and anterior margin;comparable angulation is less evident in the twospecimens ofC. parthianusbut is seen also in cranidia ofChelidonocephalus and Derikaspis from the MiddleCambrian of the Derik-Mardin inliers, southeastern

Turkey (Dean 1982a), Ordosiid? genera in which amedian plectrum is present and the anterior border maybecome long and spatulate.

Coosinoides anhuiensisLu & Zhu (1980, p. 19, pl. 5,figs. 13, 14), from North Anhui Province, occurs in themiddle of an Upper Cambrian succession that is situatedbetween the North and South China regions and includesintermediate lithologies in which the faunas exhibit mixedaffinities. Both C. parthianus and C. anhuiensis have along, low anterior area and are of broadly similar form.As far as comparison is possible, the Chinese species has

the anterior border slightly more than twice as wide(sag.) as the preglabellar field; SO is transversely straightrather than forming an anteriorly convex curve; and thepalpebral lobes are both more convergent anteriorly andlocated further forwards.

Family Damesellidae Kobayashi 1935

Subfamily Drepanurinae Hup 1953

Genus Palaeadotespik 1967

Type Species. Palaeadotes dissidenspik 1967, from the

Middle Cambrian of Queensland, Australia, by originaldesignation. According to Rushton (inTaylor & Rushton1972, p. 18), Palaeadotesis a junior subjective synonymofDrepanuraBergeron 1899 (type species, D. premesniliBergeron 1899). Lu & Zhu (1980, p. 20) placed bothPalaeadotes and D. (Spinopanura) Kushan 1973 insynonymy with Bergeronites Sun in Kuo 1965 (typespecies, Drepanura ketteleriMonke 1903). More recentlyChang & Jell (1987, pp. 22021) maintained Drepanura,Palaeadotes and Bergeronites as distinct genera, aprocedure followed here, but they considered Drepanura

(Spinopanura) Kushan (1973, p. 144) to be a juniorsubjective synonym ofPalaeadotes.

Palaeadotessp.

Plate 2 (s), (t)

Figured Specimens. NMW.95.34G.175 and 176.

Horizon & Locality. Seydiflehir Formation, lowest part ofunit b, Yayla Tepe, Locality Z.73 (rare).

Description & Discussion. A single, incomplete, abradedbut undistorted pygidium is 1 cm (estimated) broad

across the anterolateral angles, with median length(excluding half ring) of 6.5 mm (estimated). The narrowaxis, with frontal breadth 0.25 (estimated) that of thepygidium, carries at least four transversely straight axialrings on the anterior half; axial furrows almost straight,converging at about 15 to the blunt tip and smallposterior area. Pleural lobe is divided into, probably, sixpleurae that end in pleural spines, diminishing in sizefrom first to sixth. Anterior margin curves backwardsvery slightly until almost level with first ring furrow, andthen turns posteriorly through about 45 to form a stout

spine at least 6.5 mm long with traces of a furrow; thisis followed by five (?more) successively shorter andapparently unfurrowed marginal spines. As far ascomparison is possible there is a general resemblance topygidia ofD. (Spinopanura) erbeniKushan (1973, pl. 29,figs. 2, 3, 5), but the latter are relatively wider, withmore transverse anterior margin and larger first pleuralspines, and the remaining pleurae are separated by broad,deep pleural furrows. Kushan showed the lateral marginof the pygidium marked by a thickened band, outside ofwhich the pleural spines arise, separated proximally byslot-like incised extensions of the interpleural furrows,

and immediately beyond these, small fused areas occur atthe bases of the free points. A small cranidial fragment(Plate 2 (t)) is insufficient for detailed comparison; LO, L1and L2 are generally similar to those of the Iranianspecies, but L1 is proportionately larger and the posteriorfield is narrower (exsag.).

Damesellacean? Genus & Species Undetermined

Plate 3 (n)

Figured Specimen. NMW.95.34G.177

Description & Discussion. An incomplete pygidium istransversely subelliptical in outline, excluding marginalspines, with frontal breadth 16.5 cm and estimatedmedian length 6.5 cm. The large axis, although brokenoff, was originally triangular in outline, its frontal breadthslightly more than one-third that of the pygidium, and

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probably extended almost to the incomplete posteriormargin. Pleural regions of low convexity, almosthorizontal, with no distinct border furrow, and composedof three pleurae, each divided into unequal halves by abroad (exsag.), deep pleural furrow. The pleurae arebounded by faint interpleural furrows and each ends in ashort, stout, curved pleural spine which may retain tracesof anastomosing terrace ridges. The damesellaceanaffinities of the specimen are not clear, but the maincharacters correspond to those listed by Lochman-Balk (inMoore 1959, p. O316) for the Superfamily.

Family Olenidae Burmeister 1843

Olenid? Genus & Species Undetermined

Plate 3 (q), (t), (u)

Material. Figured cranidium, NMW.95.34G.178, andunfigured cranidium NMW.95.34G.179, both from theSeydiflehir Formation, basal part of unit f, at Yayla Tepe,Yo.159 (rare).

Description and Discussion. Two cranidia are preserved as weathered internal moulds. The glabella is unfurrowedapart from the shallow, transverse SO which does notreach the incised axial furrows; the latter converge gentlyforwards, where the glabellar outline forms an unbroken

broad curve. The anterior area has a length about one-quarter that of the glabella, and consists mainly of a flat

preglabellar field with a diminutive rim-like anteriorborder that is scarcely visible in the photograph. Eye lobesmall, set well forwards. Pleuroccipital furrow shallowsdistally from axial furrow, and pleuroccipital borderwidens slightly to margin. No detailed comparison waspossible, but there is a broad resemblance to Olenidgenus et species undetermined of Shergold & Sdzuy(1991, p. 209, pl. 2, figs. 32, 33) from the UpperCambrian of Spain, and to cranidia of olenids such asAcerocarina [= Cyclognathus], Boeckaspis andProtopeltura from Scandinavia illustrated byHenningsmoen (1957, pls. 2, 28; in Moore 1959, fig.196) and Westergrd (1922, pl. 16).

Acknowledgements

As on many previous occasions in Turkey, collecting of the

present material was shared by my friend Olivier Monod(Universit dOrlans). Our work in the Zap Valley Samur Da area was made possible thanks to the supportof Turkish Petroleum Corporation (T.P.A.O.), Ankara,and its geologists, whilst the villagers of Ceylanl Kyprovided kind hospitality at their mountain yayla. MrsLinda Norton at the National Museum of Wales, Cardiff,is thanked for producing the text-figures and plates. Atthe Academia Sinicas Nanjing Institute of Geology &Palaeontology, Professors Zhou Zhiyi and Chang Wentang kindly discussed related Chinese faunas andfacilitated examination of relevant specimens and

publications. I am indebted to Dr A.W.A. Rushton for hiscritical reading of the manuscript.


246

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