SOME CONSEQUENCES OF RECENT INVESTIGATIONS ON THE FAMIIN

ACANTHODIDAE HUXLEY, 1861

JAROSLAV ZAJIC

ZAJfC J. 1995. Some consequences of recent investigations on the family Acanthodidae Huxley, 1861. [Quelques cons~quences des recherches r~centes sur la famille des Acanthodidae Huxley, 1861]. GEOBIOS, M.S. n ° 19 : 167-169.

ABSTRACT

Recent investigations on the family Acanthodidae yielded new data or new interpretations. The diagnosis of the family Acanthodidae is modified. The new family Howittacanthidae nov. fam. is described. The families of the order Acanthodiformes are compared to each other.

KEYS-WORDS : ACANTHODII, TAXONOMY, DEVONIAN-PERMIAN.

RESUMI~

Des recherches r~centes sur la famille des Acanthodidae apportent des donn~es ou des interpretations nouvelles. La diagnose de la famille des Acanthodidae est modifi~e. La famille nouvelle des Howittacanthidae nov. ram. est d~crite. Les familles de l'ordre des Acanthodiformes sont compar~es.

MOTS-CL]~S : ACANTHODII, TAXINOMIE, D]~VONIEN-PERMIEN.

The author of this paper has been investigating all known Stephanian acanthodian remains from the Bohemian limnic basins (Zajfc 1985, 1988, 1944). A new species of Acanthodes has been identified (its description will be published later). Some interest ing features (e.g. mandibular joint, gill rakers, inner structure of fin spines, pectoral girdles, scales, sensory lines) have been exami- ned in detail.

The absence of paired pelvic spines has been al- ready mentioned by Fritsch 1893 (p. 66 : A. gra- cilis), Heyler 1969 (p. 39 : Acanthodes sp.) and Boy 1976 (p. 34 : A. bronni), but the importance of this phenomenon has not been recognized. Heidtke 1990a was the first to demonstrate the presence of one single unpaired spine in A. bron- ni and later (Heidtke 1990b, 1993) in A. boyi and A. tholeyi. He named it "ventral spine". I obser- ved the same situation both in the new Acantho- des species from the Bohemian Stephanian and in A. gracilis. Zidek (oral communication) infor- med me tha t all the t rue species of Acanthodes known to him have the same arrangement. I hold

this feature as so important tha t it is necessary to restrict the nominal family Acanthodidae to the genera with no paired pelvic spines. The ab- sence of spines between the pectoral spines and the anal one in Traquairichthys or Pseudacantho- des is, in my opinion, more likely a feature of the family Acanthodidae than of the Howittacanthi- dae nov. fam. The reason of this s ta tement is the close relationship of the above mentioned genera to the genus Acanthodes and the fact tha t the ventral spines of Acanthodes are very short in contrast to those of Howittacanthus. However, the t rend toward the reduction of pelvic or ven- tral spines can be observed during phylogeny. I consider necessary to emend the diagnosis of the family Acanthodidae and to establish a new fa- mily for the Austral ian Devonian genus Howitta- canthus for the above mentioned reasons.

Family ACANTHODIDAE Huxley, 1861

T y p e g e n u s : Acanthodes AGASSIZ, 1833

D i a g n o s i s - Slender acanthodiform acanthodians

168

MESACANTHIDAE CHEIRACAN- HOWITI~ACAN - ACANTHOD1DAE THIDAE THIDAE

INTERMEDIATE 1 PAIR NO NO NO SPINES

SPINES INSERTION IN SUPERFICIAL DEEP DEEP DEEP THE MUSCULATURE

PRESENCE PAIRED PAIRED PAIRED UNPAIRED OR PELVIC NONE OR VENTRAL POSITION AROUND MIDDLE DIFFERENT CLOSE TO CLOSE TO SPINES OR CLOSER TO ANAL SPINE PECTORAL SPINE

ANAL S PI2qE

LENOHT SHORT OR MEDIUM OR MEDIUM SHORT OR NONE MEDIUM LONG

GILL CHAMBER SHORT AND DEEP SHORT AND SHORT ELONGATED DEEP

BRANCHIOSTEGALS STRONG STRONG WEAK WEAK

DORSOLATERAL ABSENT ABSENT PRESENT ABSENT SENSORY LINES

SCALES SMOOTH SMOOTH OR SMOOTH SMOOTH ORNAMENTED

MANDIBULAR BONE PRESENT PRESENT OR PRESENT PRESENT ABSENT

ACANTHODES-LIKE ABSENT ABSENT PRESENT PRESENT JAWS (LONG 1986)

Figure 1 - The families of the order Acanthodiformes and comparison of their main fea- tures. Les familles de l'ordre des Acanthodiforrnes et com- paraison de leurs caractgristi- ques principales.

having no ventral intermediate spines ; fin spines deeply embedded in the body musculature ; pec- toral fin spines relatively long to body size ; no pelvic spine, but, in some cases, one short unpai- red ventral spine si tuated close to the pectoral spines ; gill chamber elongated ; branchiostegal rays weakly developed and extended only half the length of the gill chamber.

D i a g n o s i s - Slender acanthodiform acanthodians having no intermediate spines ; fin spines deeply embedded in the body musculature ; pectoral fin spines relatively long to body size ; paired pelvic spines half as long as the pectoral ones and si- tua ted closer to the anal fin than to the pectoral one ; gill chamber short ; branchiostegal rays weakly developed and short.

Stra t i gr ap h i c a l o c c u r r e n c e - ? Upper Lochko- vian ; Tournaisian-Autunian ; ? Saxonian.

G e o g r a p h i c a l o c c u r r e n c e - World-wide with the exception of South America.

R e f e r r e d g e n e r a -Acanthodes AGASSIZ, 1833 ; Traquair ichthys WHITLEY, 1933 ; ?Pseudacantho- des WHITE & MoY-THOMAS, 1941 ; Utahacanthus SCHULTZE, 1990 (?).

Stra t igraph ica l o c c u r r e n c e - Frasnian

G e o g r a p h i c a l o c c u r r e n c e - Australia

R e f e r r e d g e n u s - Howi t tacan thus LONG, 1986

R e m a r k s - This new family is considered as clo- sely related to the family Acanthodidae because of comparable features on upper jaw described by Long 1986.

R e m a r k s - Pseudacanthodes is probably syno- nym of the genus Traquair ichthys (Zidek, oral communication). Rodriguez ichthys was based on a misinterpretation of the scale histology (Schultze 1990), Utahacanthus was described only on the holotype and therefore it is not so clear (Schultze 1990 ; Fig. 1) whether it presents an unpaired ventral spine (more probably) or pai- red pelvic ones.

Family HOWITTACANTHIDAE nov. fam.

Type g e n u s - Howi t tacan thus LONG, 1986.

The following classification is based on tha t of Zi- dek 1993 :

Class Acanthodii Owen, 1846 Order ISCHNACANTHIFORMES Woodward, 1891

Family ISCHNACANTHIDAE Woodward, 1891

Order CLIMATIIFORMES Berg, 1940 Suborder CLIMATIOIDEI Miles, 1966

Family CLIMATIIDAE Berg, 1940 Family EUTHACANTHIDAE Berg, 1940

169

S u b o r d e r D I P L A C A N T H O I D E I W o o d w a r d , 1891

F a m i l y D I P L A C A N T H I D A E W o o d - w a r d , 1891 F a m i l y C U L M A C A N T H I D A E Long , 1983 F a m i l y G Y R A C A N T H I D A E W o o d - w a r d , 1906

O r d e r A C A N T H O D I F O R M E S Berg , 1940 F a m i l y M E S A C A N T H I D A E Moy- T h o m a s , 1939 F a m i l y C H E I R A C A N T H I D A E B e r g , 1940 F a m i l y H O W I T T A C A N T H I D A E nov . f am. F a m i l y A C A N T H O D I D A E H u x l e y , 1861

Acanthodopsis incertae sedis.

R I ~ F I ~ R E N C E S

BoY J.A. 1976 - D-berblick fiber die F a u n a des saar - pf~ilzischen Rotl iegenden (Unter-Perm). Mainzer geowissenschaftliche Mitteilungen, 5 : 13-85.

FRITSCH A. 1893 - Fauna der Gaskohle und der Kalksteine der Perrnformation BShrnens, 3 (2) : 48- 60. Rivnac. Praha .

HEIDTKE U. 1990a - S tudien fiber Acanthodes (Pisces : Acanthodi i) aus dem saarpf~ilzischen Rotl iegend (?Ober-Karbon-Unter -Perm, SW-Deutschland) Polli- chia-Buch, 19 : 1-86.

HEIDTKE U. 1990b - S tud ien fiber Acanthodes 3. Acan- rhodes tholeyi n. sp., ein neuen Acanthodier (Acan-

thodii : Pisces) aus dem Rotle igenden (Unterperm) der Saar -Nahe-Beckens (SW-Deutschland). Paliion- tologische Zeitschrift, 64 : 261-267.

HEIDTKE V. 1993 - S tudien fiber Acanthodes 4. Acan- thodes boyi n. sp. die d r i t t e Ar t der Acanthodier (Acanthodii : Pisces) aus dem Rotl iegend (Unter- perm) des Saar -Nahe-Beckens (ST-Deutschland) . Pal~ontologische Zeitschrift, 67 : 331-341.

HEYLER D. 1969 - Ver tebras de l 'Autunien de France. Cahiers de Palgontologie. CNRS ~d., Par i s : 312 p.

LONG J.A. 1986 - A new La te Devonian acanthodian fish from Mt Howitt , Victoria, Aus t ra l ia , wi th re- marks on acanthodian biogeography. Proceedings of the Royal Society of Victoria, 98 : 1-17.

SCHULTZE H.P. 1990 - A new acan thod ian from the Pennsy lvan ian of Utah, USA, and the d is t r ibut ion of otoli ths in gnathostomes. Journal of Vertebrate Paleontology, 10 (1) : 49-58.

ZAJ~C J. 1985 - News fmds of acan thodians (Acantho- dii) from the Kounov Member (S tephan ian B, cen- t ra l Bohemia). Vestnik Ustredniho Ustavu geolo- gickgho, 60 : 277-284

ZAJIC J. 1988 - Acanthodian (Acanthodii) j aws from the borehole Sa-2a. Vestnik Ustredniho Ustavu geo- logickdho, 63 : 221-225

ZAJfC J. 1994 - A k a n t o d i ceskgho lirnnickgho stephanu. Thesis (in Czech), Cesky geologicky Ustav. P r a h a : 109 p.

ZIDEK J. 1993 - Acanthodii . In BENTON M.J. (ed.) : The Fossil Record 2. 587-590, C h a p m a n & Hall , London.

J. ZAJIC Czech Geological Survey

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