THE

AFRICAN JOURNAL

OF

TropicalHydrobiology and Fisheries

(Afr. J. Trap. Hydrabial. Fish)

•EDITOR: J. Okedi

SUB EDITOR: S. Wanambwa (Mrs).

EDITORIAL BOARD

L.ObengN.OderoS. N. SemakulaM. HyderW.B. BanageA.M.A.Imevbore

W. A. SichoneV. O. SaguaR. E. MorrisA. F. De BontG.E.B. Kitaka

Vo.4 No.2 1975

Vol. 4 No.2 1975CONTENTS

A.ONGOMA

Page

Parasitic Fish Diseases and Their Impact onPotential Fish Production in East Africa 148

K. IBRAHIM and R. LEMA Growth Rates of Tilapia esculenta Graham and T.zillii (Gervais) under Cultivation in Ponds ofNyegezi, Tanzania 156

H. MATTHES

G. SSENTONGO

O. O. OKORIE

Key to the Families and Genera of FreshwaterFishes of Tanzania 166

Management from the Viewpoint of Lake Vic-toria Fisheries 184

On the Ecology and Explorations of the Fisheriesof an East African Rift Valley LakePart I. On the Bionomics and Population Struc-ture of Tilapia nilotica in L~ke Baringo, Kenya 192

K. IBRAHIM and R. LEMA Hybridization between Tilapia zillii (Gervais) andT. andersonii (Casteinau) at the FreshwaterFisheries Institute Nyegezi, Tanzania. 220

ANNOUNCEMENT • Availability of Salmon Pituitaries and PurifiedPituitary Hormones. 226

-II. MATTHES,Freshwaur Fisheries Institute, lVvegezi.P.O. Box 1213. Mu:anza. Tanzania.

A key to the families and genera of freshwaterfishes of Tanzania

INTRODUCTION

The purpose of this key is to facilitaterapid and accurate identification, in thefield, for fisheries workers. It is thereforebased as much as possible on externalcharacters only and an attempt has beenmade to keep it simple and straight for­ward. The only real difficulty arises inclearly demarcating the numerous cichlidgenera of the great lakes, despite the factthat these have been treated in separatesections for each lake. Moreover, it hasn'tbeen possible to revise the key to the lakeNyasa genera (taken from Jackson, 1961)to any significant extent, my experiencewith L. Nyasa fishes being limited; also, afew new genera have been or are still inthe process of being published and I un­fortunately haven't had access to thesepapers.

This key is in two parts: the first partdeals with families and the second withthe genera. Families incorporating only agenus, of cource, need no further keyingout. Similarly, mono-specific genera needonly a mention of the relevant species.

Only the true freshwater species havebeen included in this key, but a short listof marine fishes which regularlypenetrate into rivers is appended (Appen­dix 1). The geographical distributionwif-JUn Tanzania of most of the speciesme:.Jtioned has been noted as well, exceptfor those which are widespread. Thosegenera which occur only in Tanzania orare endemic to the lakes are marked withan asterisk (*). Fishes which cannot beidentified using this key should be sent toKunduchi Fisheries Institute, Dar esSalaam, as they may well be new recordsor species.

A short bibliography is appendedcovering the major publications relevantto the systematics of Tanzaniafreshwater fishes and the sources fromwhich these keys have been drawn up.

HOW TO USE THE KEY

Starting from section 1, No. 1 in everycase, read carefully through each alter­native and choose the one which agreeswith the characters of the specimen to beidentified. Proceed, following thenumbers, until you reach a family name.If the family contains more thl\n onegenus, you will be referred to a lettflr (e.g.Fam. Characidea (Cl: Proceed to sectionII IC) to key out the genus, as above. Bearin mind that in the key every word. has aprecise meaning and is important.

A minimum of ichthyological ter­minology is unavoidable and the majorones are defined here (see Fig. 1 and list ofterms).

A = Anal finC = Caudal finD = Dorsal fin (D I first, spiny,

Dorsal; D II = second, soft-rayed, Dorsal).

p = pectoral finV = Ventral, or pelvic, fin. paired

finsCh - cheekCp = caudal peduncle (l = length;

d = depth)E = eyeED = eye diameterHL = Head lengthL.J. = lower jawL.L. = Lateral line

;~~

/

167 H.MATTHES

L.L.Sc = lateral line scale seriesMx = maxillary boneNa = nostrils0 = opercular bone (gill-cover)Pmx = premaxillary bonePo = pre-opercular bonePOD = pre-orbital depthS.L. = standard lengthT.L. = total lengthT.Sc = transverse scale series

Definition of terms used in the keys:Abrupt = steeply sloping.Adipose fin = fleshy fun-like projection

behind dorsal fin, without rays..Apophyses = bony projections on the

vertebrae (ventrally situated as usedin key).

Arborescent respiratory organ = much­branching, contorted accessory organ(for air breathing) situated above gillsin Clariidae and Anabantidae.

Barbel = I slender' fleshy projectionsaround ·the mouth of certain fishes(e.g. catfishes).

Beak-like = shaped more or less like thebeak of a bird.

Bicuspid = teeth with a double point orcusp.

Branchial arch = bony arch on which thegill filaments and gill rakers aresituated; usually numbering four inthe bony fishes.

Branchiostegals = bony rays supportingthe membranes behind and below theoperculum; visible when the gillcovers are lifted and the membranesstretched.

Cephalic = refers to the head (e.g.cephalic canals: The fine sensorycanals on the head, usually underly­ing the skin and opening throughpores to the surface.

Confluent = touching or merging (toge­ther).

Conical = simple, pointed teeth.Crown = the top, usually flattened. of

certain teeth.Ctenoid = Scales with a rough, finely

serrated edge onmrface.

Cuspidat.e = teeth bearing cusps orpoints.

Cycloid = scales which are completelysmooth along the edges and on sur­face.

Decurved = curved downwards.Denticle = a scale shaped like a tooth or a

thorn.Disc (sucker-likel = flat, expanded

attachmept organ of certain fishessituated around the mouth or on thechin.

Emarginate (caudal fin) = slightlynotched along the rear edge.. .

Free border (of eye) = when the eye IS

separated from the surrounding skinby a deep cleft i.e. not covered by acontinuous skin layer, as is t.he case ihMormyridae.

Fontanel = an opening in the skull ontop of the head. covered by skin only.

Furcate = forked or deeply not.chedcaudal fin.

Gill-rakers = bristle-like or spine-likeprojections along the inner edge ofthe gill-arches. Are usually countedfrom the posterior corner or angle ofthe first arch downwards.

Gonopodium = modified Anal fin of malePoeciliidae which serves as intromit.tent sex organ (penis).

Incisiform = teeth shaped like incisors.i.e. with a sharp cutting edge.

Inferior = position of mouth on theventral side of .the head. Le. with up­per jaw or snout projecting.

Interorbital (distance) = space betweenthe eyes measured from orbit to orbit.

Mandibular = belonging to the lower jaw(mandible), e.g. mandibular barbels.arising from the lower jaw.

Molariform = teeth shaped like molars.Le. thick and blunt. with broad flat­tened crowns. for grinding.

Mouth-brooder = fish (e.g. Tilapia) whichhatch their eggs inside their mouth.

Mucus canals = or sensory canals: thincanals on the head. usually openingwith variously sized pores to the ex­terior.

Nape = the "neland Dorsal fi

Nasal = belongiJe.g. nasal barnostril.

Ocelli = rounddifferent coloalso called I

resemble fishOpercular adhes

disc-shaped. I

of the headKneria spp.

Orbit = bony eYIOtic = that ps

enclosing thlorgans, behin

Palate = the roo'Papillose = bes

fleshy projeclParietal = bone!

top part of th= gap betwel

Pharyngeal bonesituated bet\';in the throatway to dis:backwards frmouth thraufculum) and giof the head. :jaw and Jpharyngeal tteeth, will be ~

the gullet or (Pluricuspid = te

one cusp or ICharacidae).

Predatory = hunlusually with I(sharp. pointe

Produced == broced jaws. wting.

Protractile = mforward upothe extent 0

when open.Radiating striae

;.

tooth or a

expanded,ain fisheslor on the

: slightly~e.

the eye isrnding I'lkinIvered by a; thecase in

he skull ony skin only.,Iy notched

r spine-likener edge ofIlly countedor angle of

1 fin of maleas intromit

ike incisors,~dge.

uth on thei.e. with up­rlg.ice betweenrbit to orbit.~e lower jawlIar barbels,w.like molars.I broad flat­g.lapia) whichleir mouth.canals: thinilly opening!s to the ex-

Nape = the "neck" region between headand Dorsal fin Qrigin.

Nasal = belonging to the nose or nostrils,e.g. nasal barbel = arising next to thenostril.

Ocelli = round $pots with a ring ofdifferent colour around it; on Anal finalso called egg-spots because theyresemble fish eggs.

Opercular adhesive organ = a specialdisc-shaped, ribbed organ on the sidesof the head behind the eye in maleKneria spp.

Orbit = bony eye socket in the skull.Otic = that part of the head (skull)

enclosing the hearing and balanceorgans. behind and above the orbit.

Palate = the roof of the mouth cavity.Papillose = bearing papillae or small

fleshy projectionsParietal = bones covering the posterior

top part of the skull: parietal fontanel= gap between the parietal bones.

Pharyngeal bone = bone or paired bonessituated between the gill arches deepin the throat or pharynx. The easiestway to dissect them is to cutbackwards from the corners of themouth through the gill-eovers (oper­culum) and gill arches, to the rear endof the head. Pulling down the lowerjaw and pharynx floor. thepharyngeal bones. us'llally bearingteeth, will be visible at the entrance tothe gullet or oesophagus.

Pluricuspid = teeth bearing more thanone cusp or point (up to 7. in someCharacidae).

Predatory = hunting. carnivorous fishes.usually with large mouth and canine(sharp, pointed) teeth.

Produced == brought forward. e.g. produ­ced jaws. which are strongly projec­ting.

Protractile = mouth which is projectedforward upon opening. sometimes tothe extent of appearing like a tubewhen open. I

Radiating striae = lines (striae) running

Freshu.'ater Fishes of Tan:eania 168

from the centre of a scale to the edge.in a fan-shaped figure.

Rhomboidal = shaped like a lop-sidedsquare.

Rostral = belonging to the rostrum oranterior end of snout.

Serrate = like the edge of a saw, e.g.spines of Synodontis.

Spatu.late = spoon-shaped or shovel­shaped teeth.

Spawning = to lay (spawn) eggs e.g.substrate spawner, a fish whichspawns on the bottom.

Striae = fine lines or streaks.Terminal = at the end. e.g. terminal

mouth: at end of head/snout. withboth jaws of equal length.

Tricuspid = teeth bearing three cusps orpoints.

Truncate = cut straight or abrupt, (e.g.caudal finl.

Tubercles = small grain-like projections,usually seen on the skin of the head inCyprinidae.

Unicuspid = teeth with a single poi,."'lt, i.e.conical.

I. KEY TO THE FAMILIES

1. - Paired fins expanded. rayed... , 2- Paired fins a single long fila-

ment .................. Protopteridae(One genus only: Protop'terus ­Lung-fish. two species of whichhave been identified: P.aethiopicus, Lakes Victoria andTanganyika. includingMalagarasi River system; P. an­nectens brieni. Lake Rukwa, Athird, P. amphibius (Ruahal is adoubtful record).

2. - One or two dorsal fins present.. 3- Dorsal fin divided into a series

of separate finlets; scales thickand bony. rhomboidal in shape................... Polypteridae(One genus only; Polypterus -

9

a

19.-

fJhn

15. - Ifi

-I. ,

(~

S~ 16. - A

It

(5~piP.

-Aal

gc.,

(CGa!

VI

17. - N-0

(1'erTl

18. - Asaed(CMSIl

tJ:fll

- 7-9--cq

~as

- Tigerfish, Miralestes. Peter­sills and Rhabdalestes).

- Teeth all fine and slender................... Citharinidae (D)(2 genera: Citharinus andDistichodus).

10. - Teeth present. . . . . . . . . . . . . . .. 12- Teeth absent................ 11

11. - Gill - opening small, restrict­ed to the sides only; mouth in­ferior. not protractile, nobarbels; scales tiny (over 60 inlateral line) Kneriidae (E)(2 genera: Kneria andParakneria).

--Gill - opening large,' exten­ding to ventrical part of head;mouth terminal to inferior. pro­tractile, barbels present or ab­sent; scales usually large(usually less than 50 in lateralline) Cyprinidae (F).(7 genera: Barbus, Barilius.Engraulicypris. Garro, Labeo.Varicorhinus and Xenobar­bus).·

12. - Fins without spiny rays. . . . .. 13- Fins with spiny rays " 17

13. - Scales present; ventral finspresent...... 14

- Small erectile denticles insteadof scales; ventral fins absent ­Tetraodontidae. (One genus:Tetraodon - Pufferfish. with asingle species: T mbu, Mala­garasi).

14. - Gill - opening narrow, restri­cted to the sides only; skinthick, covering eye which hasno free border; scales verysmall. sunk in skin; caudalpeduncle long and thin, tail-finsmall Mormyridpe (G).'(7 genera: Gnathonemus, Hip­popotamyrus, Marcusenius,Mormyrops, Mormyrus,Petroceplt.alus and Pollimyrus).

- Gill - opening extending toventral part of head. eye with

8

65- Body very elongate, eel-like...

5. - Dorsal fin preced~d by a seriesof small, separate spines. oftenembedded in the flesh ............. Mastacembelidae.(Only one genu~:

Mastacembelus - Spiny eel,with 12 spp (11 endemic) in L.Tanganyika, one in L. Nyasaand one in L. Victoria and someof the rivers. e.g. Rufigi).

- Dorsal fin not preceded byspines Anguillidae(Only one genus: Anguilla ­Freshwater eel, with 3 spp.: A.mossambica, A. nebulosalabiata and A. bicolor bicolor.in the coastal rivers).

6. - Two dorsal fins present. . . . . . . 7- One single dorsal fin. . . . . . . . .. 10

7. - Second dorsal fin small.adipose .

- Second dorsal fin rayed .Centropomidae (A). (2 genera:Lates and Luciolates - Nileand Lake Perch).

8. - Mouth, if large, with strong,large teeth .

- Mouth large, teeth small ................... Salmonidae(2 genera: Salmo - Trout, andSalvelinus - Brook-trout. in­troduced into various highlandstreams).

9. - Teeth large and pointed orshort. pluricuspid and com­pressed, or thickened(molariform). ; .. Characidae (C)(6 genera: Alestes,Bryconaethiops, Hydrocynus

Bichir, with two species: P.endlicher~ and P. ornatipinnis,L. Tanganyika and Malagarasi,the latter also in Rukwa).·

3. - Scales or denticles present. . . . 4- Scales absent; well-developed

barbels around mouth (Catfish) 184. - Body shape normal, not eel-like

169 H. MATTHES

J

•I

'l­ot

,

t .

Freshwater Fishes of Tancania 170

stes. Peter­tesl.lender.....arinidae (D)

'arinus and

............ 1211

lla11, restrict­lly; mouth in-•tractile, noily (over 60 inKneriidae (E)(neria and

Ilrge,. exten-part of head;

o inferior, pro­present or ab­lsua11y largen 50 in lateralyprinidae (F).bus, Barilius,Garra, Labeo,md Xenobar-

iny rays...... 13rays , 17

ventral fins14

lnticles insteadI fins absent ­

(One genus:Ifferfish, with aT. mbu, Mala-

narrow, restri­les only; skineye which has'; scales very

skin; caudalIld thin, tail-finIrmyrid~e (G),'-honemus, Hip­Marcusenius,

Mormyrus,od Pollimyrus).extending to

head, eye with

free border, scales small tolarge, caudal peduncle and finnormal."..................... 15

15. - Dorsal fin above or behind analfin .. _.. .... ... . ... . . .. . . . . .. 16

- Dorsal fin above ventral fins.................. Clupeidae (H)(2 genera: Limnothrissa andStolothrissa - L. Tanganyika).

16. - Anal fin below dorsal fin inmales.... Cyprinodontidae (L).(5 genera: Aplocheilichthys,Cynopanchax (doubtful), Lam­prichthys, Nothobranchius andPantanodon ).

- Anal fin anterior to dorsal finand modified into agonopodium in males .. . . . . . . . . . . . . . . . . . Poeciliidae(One genus and species only:Gambusia affinis - introducedas a mosquito-eater intovarious ponds).

17. - Nostrils paired, 2 on eacb side. 18- One nostril on each side ofhead

................. Cichlidae (J)(Numerous genera, mostlyendemic to Lake Nyasa,Tanganyika and Victoria).

18. - Anal fin with 2-4 spines, Dor­sal 13-19 spines, opercularedge smooth... Centrarchidae.(One genus and species:Micropterus salmoides ­small-mouthed Black bass, in­troduced into variousfishponds).

- 7-11 Anal spines; Dorsal9-10 spines; edge of oper­culum serrated - Anaban­tidae.(One genus: Ctenopoma, with 3spp. of which two, C. ctenotisand C. multispine, doubtfullyrecorded from L. Nyasa andone C. murie~ from L. Victoriaand L. Tanganyika basins).

19. - Rayed dorsal fin present. . .... 20- No rayed dor~al fin, only

adipose dorsal present

............ Malop teruridae.(One genus and species:Malopterurus electricus - elec­tric catfish, L. Tanganyika).

20. - Rayed dorsal fin short. . . . . . .. 21- Rayed dorsal fin and anal fin

long (Clariidae lK)(6 genera: Bathyclarias,Clarias, Dinotopterus, Hetero­branchus, Tanganikallabes andX enoclarias).

21. - Anal fin short (8-15 raysl.... 22- Anal fin long (over 40 rays)....

............... Schilbeidae (Ll(3 genera: Eutropius,Pareutropius and Schilbel.

22. - First ray of dorsal and pectoralfins spiny................... 23

- First ray of dorsal and pectoralfin soft Amphiliidae.(One genus: Amphilius, with 4spp.: A. kreffti (Panganil, A.jacksoni (Kageral. A. platychir(wide-spread), A. uranos~opus

(Wami).23. - Barbels not branched or mouth

not enlarged into a sucker-likedisc Bagridae (Ml(6 genera: Bagrus,Auchenoglanis, Chrysichthys,Leptoglanis, Lophiobagrus andPhyllonemus I.

- Barbels branched (us~ally onlythe mandibular onesl or mouthenlarged into a sucker-like disc. " Mochokidae (Nl(3 genera: A topochilus,Chidoglanis, Synodontis)

II. - KEY TO THE GENERA

(A) FAMILY CENTROPO·MIDAE

- Dorsal fins close to each other,barely separated Lates.(3 spp. in L. Tanganyika: L.angustifrons, L. mariae and L.microlepis; one in L. Victoria­introduced: L. 1&iloticus).

171 H. MATTHES

- Dorsal fins well separated...... . . . . . . . . . . . . . . . . . •LuciolateslOne species: L. stappers~ L.Tanganyika; another species L.brevis, described from a singlespecimen, has not been foundsince and is doubtfull.

IBI FAM: SALMONIDAE

- Dorsal II-III 8; caudalemarginate SalvelinuslOne sPecies: S. fontinalis - in­troduced)

- III-IV 9-10; caudal forked......................... Sa/rno12 species: S. trutta - Browntrout, and S. gairdneri - Rain­bo:w trout, introducedl.

IC) FAM: CHARACIDAE

1. - Mouth small; teeth cuspidateand compressed or molariform

- Mouth large, teeth unicuspidand fang-like..... Hydrocynus12 species: H. goliath IL.Tanganyika) and H. vittatus ­Tigerfish).

2. - Inner teeth molariform (in up-per jaw especially) ,.

- Teeth of inner row compressed,cuspidate; adult size small....

3. - Teeth in upper jaw cuspidate.in 3 rows. those of the 2 innerrows molariform .Bryconaethiops.lOne species: B. boulengeri ­Malagarasil

- Teeth in upper jaw cuspidate.in 2 rows, the inner rowmolariform Alestes(7 species: 2 endemic to LakeTanganyika. 1 to Lake Vic­toria).

4. - Two small conical teeth pre­sent behind single row of teethin lower jaw Micralestes(2 specia:.M. stormsi and M.

2

3

4

vittatus L. Tanganyika. and athird unconfirmed record of M.acutidens in the Easternriversl.

- No teeth present behind singlerow in lower jaw. . . . . . . . . . . . . 5

5. - Parietal fontanel absent: 20gill-rakers on first branchialar.ch; 32-34 scales inlongitudinal line; a large darkspot on caudal base.. Petersius(l species: P. conserialis,Kingani IRuvul.

- Parietal. fontanel present;17-16 gill-rakers; 35-39longitudinal scales. a duskystripe on sides... Rhabdalestes(2 species: R. letaitpi - L. Jipe.and R. tangensis - Umboriverl.

(D) FAM: CITHARINIDAE- Scales cycloid. mouth wide ­

........... ~ ..... '. Citharinus(3 species: C. c"ongicus - Rufigibasin. C. gibbosus - L.Tanganyika basin. and C. latusI?l Kingani (Ruvul river.

- Scales ctenoid. mouth narrow.. Distichodus(5 species: 3 from L.Tanganyika basin. and 2 in theEastern (Coastall rivers).

(E) FAM: KNERIIDAE- 9-10 rays in pelvic fin; lateral

straight; no opercular adhesiveorgan in males..... Parakneria(One species: P. spekei ­coastal rivers).

- 8 rays in Pelvic; lateral linedecurved or nearly straight: anopercular adhesive organ pre-sent in males Kneria(3 spp: K. angolensis - Rukwabasin: K. auriculata - L.Tanganyika basin, and I?) K.taeniata).

IF) FAM: CYPRINIDAE1. - No barbels on chin. . . . . . . . . . . 2

-A pairchin

lOne smonly; X.region).

2. - Dorsal fiof or 0 vel

- Dorsal j

behind tlterminal.

3. - Dorsal fiadvance <

16 SpeciErivers, 2 fL. Tang81

- Dorsal fiJsituated I

species...

15 speciesMalagarspinifer), 'Nyasa (E.congicu~

TanganyiJVictoria (1

4. - Dorsal firadvancemouth iJwith a h(Jwell-devewith a su

- Dorsal i

pelvicsorbehind pl

position 1

5. - Lips varhorny eelposition,flap pre(Many stify; 2species,longitudiwith 8C

striae).- Upper Ii

ferior a

ganyika. and aled record of M.the Eastern

it behind singlew , 5leI absent: 20first branchial4 scales inLe; a large darkbase.. Petersius~. conserialis,I.~anel present;akers; 35-39cales, a dusky. .Rhabdalestestaupi - L. Jipe,!nsis - Umbo

RINIDAEmouth wide ­

, ., ... Citharinustngicus - Rufigibbosus - L.sin, and C. latuslVU) river.mouth narrow.... Distichodus

3 from L.sin, and 2 in theall riversl.

IDAE>elvic fin; lateralercular adhesive..... Parakneria

P. spekei -

vic; lateral lineIU'ly straight; an!sive organ pre-........ Kneriatensis - Rukwariculata - L.Isin, and (?l K.

fIDAE:hin........... 2

- A pair of barbels under thechin (lower jaw)................ ·Xenobarbus(One small, doubtful speciesonly; X. loveridgei - Mwanzaregion).

2. - Dorsal fin situated in advanceof or over pelvic fins. . . . .. . . . . 4

-Dorsal fin situated entirelybehind the pelvic fins; mouthterminal, large.. . . . . . . . . . . . . . 3

3. - Dorsal fin mainiy situated inadvance of the anal fin ." Barilius(6 species: 1 from Easternrivers, 2 from L. Nyasa, 3 fromL. Tanganyika basin).

- Dorsal fin almost or entirelysituated above anal fin; smallspecies ............... Engraulicypris(5 species: 1 from Rufigi andMalagarasi systems E.spini{er), one each from lakesNyasa (E. sardella) Rukwa (E.congicus rukwaansis),Tanganyika (E. minutus) andVictoria (E. argenteus).

4. - Dorsal fin mainly situated inadvance of pelvic in base;mouth inferior, small; jawswith a horny cutting edge andwell-developed papillose lips orwith a sucking disc on the chin 6

- Dorsal fin situated abovepelvics or slightly in front of orbehind pelvic fin base: mouthposition variable. . . . . . . . . . . . . 5

5. - Lips variably developed; nohorny edge on jaws; mouthposition variable; no rostralflap present Barbus(Many species, difficult to iden­tify; 2 main groups: i.e. largespecies. with scales striatedlongitudinally, and small spp.with scales bearing radiatingstriae).

- Upper lip poorly developed, in­ferior absent; a horny cutting

Freshwater Fishes ofTanzania 172

edge on jaws; mouth inferior;rostral flap present .. Varicorhinus(5 species, 4 from LakeTanganyika basin and 1 fromLake Nyasa; V. nyasensis).

6. - A sucking disc developed onthe chin. confluent with lowerlip; no rostral flap; gill­openings restricted to the sides....................... Garro.(2 species: G. johnstoni - L.Victoria basin and Pangani (?)- and G. dembeensis (1) ...:..Kilimanjaro).

- No sucking disc present, lipsfleshy, papillose; rostral flappresent; gill-opening extendingonto ventral side ~ of head;tubercles usually present onsnout LabeoU1 species).

(G) FAM: MORMYRIDAE1. - Anal fin 3/p to 2 times as long

as dorsal fin. . . . . . . . . . . . . . . . . 2- Anal fin less than '12 the length

of the dorsal fin..........•...................... Morrnyrus(2 species: M. kannume ­elephant-snout fish, L. Victoriabasin and M. longirostris ­Eastern rivers andMaragarasi).

2. - 10-36 teeth implanted alongthe middle of each jaw. . . . . . . . 3

- 3-10 teeth confined to themiddle of each jaw. . . . . . . . . . . 4

3. - Mouth wide, terminal; bodyelongate Morrnyrops(One species: M. deliciosus ­bottle-nose. L. Tanganyika andL. Nyasa basins).

- Mouth small, inferior; bodyshort :' Petrocephalus(One species: P. catostoma ­Lakes Nyasa. Victoria andEastern rivers).

4. - M~uth terminal. with a fleshyswelling on chin or a single

2. -2

:~•I(

tnc,hff

r1 I 3. - TSE

-Tlarprbildu. .

(14. - Pr

lilllal

-Pteylaic

(2pi

5. - HIi'CI

n

'.-fIi

FAM: CYPRINODONTIDAE

· "I,iflll/of II rissa(One species: L moiriol/Lumpu).

1. - Anal fin with less t.han 24 ruys- Anal fin with 24-:iO rays.....

· ·I,ampri('h t hys(One species: L. tanuunicunlls- L. Tanganyika~.

2. - Teet.h present. .- Teeth absent; Dorsal 7-8 rays;

Anal 20-21. ..... Pantanodon(One species: P. paduxys ­coastal streams and swamps.arso in Kenya).

3. - Dorsal with 7 - 11 rays; Anal13-16 .

- Dorsal wit.h 14-18 rays; Anal14-19 Nofhol,runchills(6 species, some douhtful).

4. - Teeth in outer row not greatlyenlarged into canines .· Aplocheilichfhvs.(5 species).

- Teeth in out.er row of both jU'NSenlarged. curved, canine-like..· ·Cynopanchax(One species: C hukohanlls ­L. Vict.oria: doubtfully distinct.from Aploch eilich t hyspumilusl.

(a) From L. Nyasa

1. - Head broad, interorbital withnot more than 3 t.imes in headlength; teeth tricuspid, neverconical; a black "tilapia" spotat base of soft part of dorsal finin young _. Tilapia(7 species, in 2 sub-genera: T.(Tilapia) rendalli (melano­pleura), T. (T) sparmani, T.(Sarotkerodon) harangae, T. (S)

lidole, T. (S) squamipinnisJ.- Head narrow, interorbital

(J) FAM: CICHLIDAE

(I)

- Snout narrow. pointed: noteeth on palate .· ·Stolothrissa(One species: S. tanganicae ­Dagaa).

- Snout broad and blunt: teethon palate (vomer) .

(H) FAM: CLUPEIDAE

173 H.MATTHES

barbel. 5- Mouth terminal to sub­

terminal, no barbel, no fleshyswelling on chin. . . . . . . . . . . . . . 6

5. - A fleshy swelling on chin; nobarbel A!arcusenius(5 species, one from L. Nyasa(A!. nyase~sJs), one from L. Vic­toria (A!. victoriae), one from L.Tanganyika basin (A!.stanleyanus), 'one fromRuvuma and Rufigi (A!. liv­ingstoni) and one wide-spread(A!. macrolepidotus); untilrecently, these species were allin the genus Gnatho.nemus).

- A single, thick barbel on chin..· Gnathonemus(One species: G. longilJarbis ­L. Victoria and L. Tanganyikabasins).

6. - Mouth sub-inferior; lower jawwith a strong bony chin; Dorsaloriginating in advance of Analfin; dorsa1 profile more strong­ly curved than Ventral profile.· Hippopotamyrus

(2 species: H. discorhynchus ­wide-spread, and H. grahami ­L. Victoria).

- Mouth terminal: lower jawwithout bony chin; Dorsaloriginating above Anal; dorsaland ventral profiles more orless symmetrical. .· Pollimyrus(One species: P. nigricans, L.Tanganyika and L. Victoriabasins).

--- -~-------=- ~_-~_~_..o-;_

,•

...-,

.,.,, Ii

*/,iml/othrisslIL moic/ol/

NODONTIDAE

less than 24 rays24-30 rays.....· */,amprich thysL. tanl(anicanl/s

yikal........

Jo •• ••••• •

:Dorsal 7-8 rays;· .... Pantanodon

I: P. padoxvs ­lms and swamps.

al.7-11 rays; Anal.................14-18 rays: Anal., Notho/Jranchil/s

orne douhtful).l.er row not ~reatly

,0 canines ,. Aplocheilich thys.

cer row of hoth ja'Nsllrved. canine-like..· ... *Cynopanchax

lS: C. hl/kohanl/s ­: douhtfuUy distinct4plocheilichthv s

HLIDAE

.. Nyasa

'ld. interorhital withthan 3 t.imes in headeth tricuspid, neverblack "tilapia" spotsoft. part of dorsal fin., _. Tilapia:. in 2 sub-genera: T.

rendalli (melano­r. (T) sparmani. T.odon) harongae. T. (S.)(S.) squamipinnis).arrow. interorbital

width over 3 times in headlength. teeth conical totricuspid: no "tilapia" mark ondorsal. . . . . . . . . . . . . . . . . . . . . . . 2

2. - Third vertebra with inferiorapophyses meeting below dor-sal aorta ,.... 6

- Inferior apophyses on thirdvertebra. if present, notmeeting below dorsal aorta. . . . 3(5 large. well-marked speciesonly: all with ofJIiql/e blackbands on body: large pr€datorymouths and conical teeth. ex­cept for Lichnochromis. whichhas a narrow mouth and dif­ferent teeth).

3. - Teeth in upper jaw in 2 or moreseries. conical. . , . . . . . . . . . . . . . 4

- Teeth in a single series. exceptanteriorly: outer teeth com­pressed. entire. notched orbicuspid: premaxillaries pro­duced forwards and beaklike... .. , *Lichl/ochromis

(1 species: L. aCl/ticepsl.4. - Premaxillaries normal or beak­

like: eye normal: 1-2 markedlat eral bands................ 5

- Premaxlllaries not beak-like:eye very lar~e: body silvery.lateral bands faint: teeth con-ical. in 2 species ............... , *Diplota:codon(2 species: IJ. argentells and D.pallididorsalis 1.

5. - Head normal. jaws not beak­like: mouth large: no scales oncaudal fin: lou'er lateral bandnot obliqlle". Serranochromis(One species: S. robl/stl/sl.

- Head laterally compressed(narrowl; jaws beaked andturtle-like: teeth small. conical.in 3-4 series anteriorly: caudalfin with fine scales: 2 markedoblique lateral bands. the up­per on the dorsal outline (alongbase of finl. ... *Aristochromis(One species: .4.. christyil.

Freshu'ater Fishes of Tanzania 174

6. - Otic region of skull and canalsof head swoUen:. . . . . . . . . . . . . . 7

- Otic region and mucus canalsnot swollen. . . . . . . . . . . . . . . . . . 8

7. - 2-4 series of scales on cheek. .· Trematocranus(3 species).

- 0-1 series of scales on cheek.· *Aulonona(3 species).

8. - Scales On nape. chest and cneekvery small. dentition complex("Mbuna"-group of fishes ­rocky habitatl............... 16

- Scales on nape. chest and cheeknot much smaller than on restof body: teeth simpler and lessnumerous (except inDocimodus. Chilotilapia andCorematodusl. . . . . . . . . . . . . . . 9

9. - Teeth in 1-5 series. more orless arranged in rows. . . . . . . .. 10

- Teeth tiny. club-shlilped. verynumerous, in very broad bands(at least series) .· *C'o.rematodus(2 species: C'. shiranus and C.teenia t II S l.

10. - Teeth in 1-3 rows. small. iflarge. conical and sparselyspaced. never massive andstout. . . . . . . . . . . . . . . . . . . . . .. 12

- Teeth in 3-5 s~ries. massiveand stout. shaped like grains ofwheat with a groove on theouter surface or strong. in­cisiform. unicuspid. or with alarge middle cusp and 2 smalllateral cusps: mouth wide.. , .. 11

11. - Jaws strong. teeth stout. in­cisiform. unicuspid fadult) witha large middle cusp and a pairof small lateral cusps Iyounglin 4-5 well-separated series:an obliqlle black band fromnape to caudal. ... *Docimodus(One species: D. johnstonil

- Most teeth shaped like grainsof wheat. bluntly pointed in­wards with a groove on the

175 H. MATTHES

outer surface louter teethbluntly bicuspid in young); 2dark bands on each side fromhead to caudal fin. one on mid­dle of each side, one above up­per lateral line - *Chilotilapia(One species: C rhoadesi).

12. - Premaxillarie~ ·beak-like; teethlarge, conical, spaced; mouthlarge (predatory], or: jaws pro­truded by produced premax­illaries; teeth simple, withslend~r shafts and compressedcrowns. the outer obliquelytruncate and incJined towardsthe mid-line of the jaw. . . . . . .. 15

- Premaxillaries not beak-like;teeth. rarely all tricuspid,generally the inner tri-or bi­cuspid, outer bicuspid to con­ical; sometimes with inner con-ical and outer bicuspid. or allconical; some with inner teethtricuspid and outer withslender shafts and compressedobliquely truncated crowns. .. 13

13. - Mouth usually oblique; headprofile not steeply sloping;outer teeth not curved behindinner. . .. . . . . . . . . . . . .. . . . .. .. 14

- Mouth horizontal, profilesteeply sloping; outer series ofteeth in lower jaw curved in­wards posteriorly, behind innerseries: a gap between the teethat the centre of the lower jaw... . . . . . . . . . . . . . . . . *Lethrinops(24 species).

14. - Caudal fin truncate toemarginate: Anal fin bearingocelli or egg-spots in male.................... Haplochromis(about 112 species).

- Tail well-round: Anal withoutocelli but bearing light streakyspots posteriorly, often alsowith an orange tip in male................ PseudocrenilabruslOne species: P. philander -

rivers).15. - Conical. enlarged anteriorly.

spaced; body silvery. mouthlarge,predatory ............ ·Rhamphochromis(8 species).

- Teeth simple. with slendershafts and compressed crowns;outer obliquely truncate andinclined towards mid-line; jawsprotruding; usually a series ofspots along upper side of body'.· , _ ·Hemitilapia(One species: H. oxyrhynchus).

16. - Pharyngeal teeth tiny. densely. .crowded posteriorly " 17

- Pharyngeal teeth neithernumerous nor crowded. thosein the middle series becominglarger posteriorly............ 22

17. - Teeth not all unicuspid , 18- Teeth all conical. . ·Cynotilapia

(One species: C. atra).18. - Mouth terminal; jaw curved;

no fleshy snout over upper jaw 19- Mouth inferior. jaw straight,

usually a fleshy nose-like snoutover upper jaw .· . . . . . . . . . . .. •Labeotropheus

(2 species: L. tuelleborni and L.trewavasae).

19. - Snout pointed, teeth in narrowbands, not all tricuspid. . . . . .. 21

- Snout blunt. teeth all tricuspidin broad bands.... Petrotilapia(One species: P. tridentiger).

20. - Outer teeth normal straight....never conical: jaws equal. . . . .. 21

- Outer teeth slender. curved.protruded. conical or bicuspid:lower jaw shorter than upper..· *Gephyrochromis(2 species: G. moorei and G.lau·sil. -

21. - Teeth forming curved ortransverse bands anteriorly;outer series bicuspid and 2-7i.nner tricuspid series; a seriesof enlarged conical teeth ateach side of the upper jaw;

teeth inangles to........(12 SpeciE

- Teeth aSlin the upelined tOl

(= mid-liI.........(One sped

22. - DentitioPseudotro

J

..........(6 species).

- Teeth eithEedt in a n81pluricuspid

23. - Snout sharfrom abo,long, dirpointed ...(2 species: .caeruleusl.

- Snout bluntting; moutlbands of tetened, shall........(One specie!

(bl From u

1. - Anal fin wit- Anal fin wit

2. - At least SOil

the outer ro- Teeth in

tricuspid (botherwisel..

3. - Dorsal fin 11teeth all tripartly bicu

- Dorsal 12tricuspid,conicaL ...

4. - 10-16 gfpart of 1st..........(5 speciesI.

- 18-27 gill-

anteriorly.y. mouth

.o •••••••••

hochromis

ith slenderISed crowns;:'\lncate andlid-line; jawsy a series of8ide of body'.-Hemitilapia:r:yrhynchus).tiny, densely~ly........ .. 17!th neitherowded. thoseies becoming,............ 22~spid....... 18. *Cynotilapialfra).; jaw curved;lver upper jaw 19jaw straight,

lose-like snout............ .o •

r.abeotropheusllebomi and L.

.eeth in narrowicuspid....... 21ith all tricuspid... Petrotilapiatridentiger).

)rmal straight>lWS equal. .... , 21lender, curved.,calor bicuspid:,er than upper..'Jephyrochromismoorei and G.

rig curved orlnds anteriorly;cuspid and 2-71 series; a series:onical teeth atthe upper jaw;

teeth in outer row at rightangles to the jaw ............. *Pseudotropheus02 species).

- Teeth as above but outer seriesin the upper jaw obliquely in­clined towards the symphysis(= mid-line of jaw) , " ..· *Cyathochromis(One species; C obliquidens).

22. - Dentition as inPseudotropheus .· Melanochromis(6 species).

- Teeth either long. conical, curv-ed. in a narrow mouth or short.pluricuspid. in a wide mouth.. 23

23. - Snout sharply pointed (as seenfrom above); anterior teethlong, directed forwards.pointed. . . . . . . Labidochromis(2 species: L. vellicans and L.caeruleus I.

- Snout blunt; lower jaw p~ojec­

ting; mouth broad with widebands of teeth. the outer flat-tened. sharp. bicuspid .· *Genyochromis(One species: G. mento)

(bl From Lake Tanganyika

1. - Anal fin with 3 spines. . . . . . . . 2- Anal fin with 4-10 spines.... 43

2. - At least some tricuspid teeth inthe outer row jaws. . . . . . . . . . . 3

- Teeth in outer row nottricuspid (bicuspid. conical orotherwise) , 10

3. - Dorsal fin with 15-20 spines;teeth all tricuspid (sometimespartly bicuspid in outer row). . 4

- Dorsal 12-15 spines; teethtricuspid. sometimes partlyconical. .. .. . . 5

4. - 10-16 gill-rakers (on lowerpart of 1st gill archl .· *Petrochromis(5 speciesI.

- 18-27 gill-rakers.... " Tilapia

( S a rot her 0 'd 0 n )(PART, i.e. 2 species: T.karomo and T. tanganicae).

5. - 34-43 scales in longituc:lina1line. . . . . . . . . . . . . . . . . . . . . . . . . b

- 48-64 scales in longitudinalline... *Cyathophary~ (PART)(One species: C. furcifer).

6. - Depth (of body) less thim 4times in standard length. . . . . . 7

- Depth 5 times in standardlength; snout projecting;mouth inferior.. *Asp1'Oti14pia.(One species: A. leptura).

7. - Teeth in narrow bands,tricuspid or partly conical,directed forwards in lower jaw. 8

- Teeth in broad band~, alltricuspid, lower external teethnot directed forwards......... 9

8. - Pharyngeal bone heart-shaped,with long anterior process..... Cardioph{l.ry~

(One speCies: C. schoutedepi).- Pharygeal bone sub-triangular

......... *Lestradea persic~.

(2 sub-species).9. - Teeth all tricuspid in many

rows. . . . . . . . .. *Cunningtoilia(One species: C. longiven­tralias)

- Teeth tricuspid in 3-5 rows,except along sides where asingle row of conical teeth ispresent .... *Ophthalmoti14pia(One species: O. boops).

10. - 27-42 scales in longitudinalline. .. . . 11

- 44-96 scales in longitudinalline _ _ 34

11. - Teeth in external row at leastpartly bicuspid.............. 12

- Teeth in external row notbicuspid. . . . . . . . . . . . . . . . . . . . 18

12. - Mouth terminal, snout profilenot abrupt, jaws sub-equal.. " 13

- Mouth sub-terminal, profileabrupt, lower jaw shorter.................... *Simochromis(4 species).

i

•

177 H. MATTHES

13. - Lips normaL................ 14- Lips thickened. expanded.....

............... ·Lobochilotes(PART)(One species: L. labiatus).

14. - Forehead without a bump inadult; colour pattern without 6broad vertical dark bands. . . .. 15

- Forehead bearing a large bumpin adult; 6 broad verticalstripes on sides ......... ·Cyphotilapia (PART)(One species: C. frontsa)

15. - No dark "tilapia" spot at baseof soft dorsal fin; depth of body2'12-3% times in standardlength. gill-rakers 6-14... . .. 16

- "Tilapia" mark present; depth1%-3 times in std. length: gill-rakers 7-9 or 20-27 ............... Ti/apai (PART)(3 species: T. (Sarotherodon)nilotica, T. (Tilapia) rendalli(=melanopleaura), and T. (T)sparmanni - upper reaches ofrivers, in S.W. Tanzania. in­troduced?).

16 - Caudal fin emarginate; 10-14gill-rakers. . . . . . •Limnoti/apia(3 species: L. dardennei, L.loocki and L. t"rematocephala).

- Caudal fin roundf"l or sub­truncate; gill-rt.Kers 6-9(12-13 in one species). . 17

17. - Chest and cheakscaly ......... Haplochromis (PART)(4 species).

- Chest and cheak naked ............... ·Orthochromis(One species: O. malagarasien­sis).

18. - Less than 20 spines in dorsalfin. . . . . . . . . . . . . . . . . . . . . . . . .. 19

- Over 20 spines in dorsal. . . . .. 3219.-See Nos. 13 and 14:

Lobochilotes and Cyphotilapia(Adults) (PART).

- If lips normal and no bump onhead........................ 20

20. - No large sensory canals. withwide pit-like openings on head. 21

- Large cephalic canals withwide pit-like openings present. 30

21. - External branched ray ofpelvic fins about twice as longas internal ray; only 2 lateralline canals on body. . . . . . . . . .. 22

- External soft ray of pelvicsless than twice as long toshorter than internal ray; often3 lateral line canals present. .................. ·Xenotilapia(12 species).

22. - External teeth in lower jaw notdirected horizontally forwards 23

- External inferior teeth directedmore ur less horizontally for-wards 27

23. - Depth of body less than 4times in standar~ length; or, ifmore, over 19 gill-rakers. . . . .. 24

- Depth 4.5-4.8 times in Std.length; 13-15 gill-rakers................. " ·Leptochromis(One species: L. calliura).

24. - Body depth 2.65 to 4.65 timesin Std. length; 10-18 giil­rakers or, if more, body over 4times as long as deep (20-24gill-rakers); upper lateral linescales 21-27 or, if more, bodyover 4 times as long as deep;Dorsal XIV-XVII 8-11 (orXII-XV 13-18 in elongatespecies or XV 14-15, in Ser­ranochromis); caudal fin forked(elongate species) to rounded.. 2

- Body depth 2.4-3.3 in Std.length; 15-22 gill-rakers; up­per late'raI line with 2g-38scales; Dorsal XII-XIV12-16, Caudal fin forked.....•........ ·Ophthalmochromis

12 species': 0. n~sutus, O. ven­tralis. one subspecies: O. ven·tralis heterodontus).

25. - Head not spottea; cneek scally............................ 2.

- Head spotted and marbled

VI

IC26. - 1-

A

OJ- 6­

An(Or

Ma27, - Tee

tenand

- Teelintelconsoutel

28. - Pharnone

- Phaf~

poste10-1lines.(2 SpE

pleurc29. - 12-1

blackfin; b_(One:

- 15-2deep.

30. - Two Iin Ion

- Only27-3line. ,(8 sm

31. - 33-~

raker(One

- 31-~

rake](On

32. - Tee- Tee

(One

Freshll'alpr Fi.•hes of Tanzania 178

33. - Anterior teeth markedly longer

than those on sides: snoutdeeurved: mouth sub-inferior... , Tanganicodus(One species: T. irsacae).

- Anterior teeth not longer:snout profile approximatelystraight; mout-h-terminal. .......... , *Spathodus,(2 Species: S. erythrodon and S.marLieril.

34. - Teeth in several rows. . . . . . . .. 3f>- Teeth in a single row. . . . . . . .. 40

35. - Pharyngeal teeth implanted ona subtriangular surface: lengthof snout equal to or longer thaneye mamc! fir. . . . . . . . . . . . . . . .. 36

- Pharyngeal teet.h all tiny.densely set on a concave, near­ly circ'ular surface: snout eqwl:to or shorter than eye... '.' ....· .... *Cyathopharynx (P,ARTI(One species: ('. {urci(er).

36. - Dorsal profile normal: bodydepth over 2.75 times in,stan-dard length " 37

- Dorsal profile very high (con­vex): ventral profile nearlystraight; depth 2.3-3 times inSt.d. length, teeth small, con­ical, in 4-5 s(·ries ....Ty/ochromis(One species: T. poLyLepis).

37. - Pharyngeal teeth all small orconical: two lateral lines;60-95 scales in longitudinalline. . . . . . . . . . . . . . . . . . . . . . . .. 38

- Pharyngeal teeth molariformposteriorly; 44-59 longi­tudinal scales; usually il laterallines present. ' .· *Grammatotria(one species: G. LemaireO.

38. - Lower jaw projecting. anal finwith 12-18 soft rays 39

- Lower jaw not projecting: analfin with 8-11 soft rays; colourgreenish-yellow .· *BouLengerochromis

(One species: B. microlepis -

with black: ck:ok .L.lced ......... HapLocltromis (PART)(One species: H. horei).

26. - 1-·5 rows of scales on cheek:Anal fin III 7-9 or III 12-13.· *Limnochromis(11 species).

- 6-8 rows of scales on cheek:Anal IT I I 1. .. Serranochromis(One- -specip.,: S. janus ­Malagarasil.

. 27, - Teeth in 2-3 distinct rows, in­ternal teeth pointing backwardand as large as the outer teeth.· (See No.8).

- Teeth in 2-5 inq,istinct rows.internal teeth not recurved andconsiderably smaller than theouter. . . . . .. . . . . . . .. . . . . .... 28

28. - Pharyngeal teeth all small,none markedly enlarged. . . . .. 29

- Phafyngeal teeth enlarged, theposterior ones sub-molariform:10-12 gill-rakers; 2 laterallines *CaLLochromis(2 species: C. macrops and C.pLeurospilus) .

29. - 12-14 gill-rakers; a roundblack spot on the spiny dorsalfin: body elongate... *Ectodus(One species: E. de:campsi).

- 15-22 gill-rakers, body formdeep (See No. 24· . . . . . .. *OphthaLmochromis).

30. - Two lateral lines: 31-36 scalesin longitudinal line. . . . . . . . . .. 31

- Only one lateral line present;27-31 scales in longitudinalline *Trematocara(8 small species). .

31. - 33-36 scales: 17-20 gill-rakers *A uLonocranus(One species: A. dewindti).

- 31-33 scales: 13-14 gill­rakers.. H apLochromis (PART)(One species: H. benthicoLa)

32. - Teeth blunt. in a single row. .. 33- Teeth spatulate, in 2-il rows..

........ *Eretmodus(One species: E. cyanostictus)

27........l; .'l~ss than ~ar~ length; or. If

24gill-rakers .8 times in Std., gill-rakers.... :. *Leptochromls

~. caLliura)..65 to 4.65 tim.esth; 10-18 g111­lore, body over 4, as deep (20-24~pper lateral lineor, if more. bodyas long as deep;

-XVII 8-11 (or:-18 in elongateV 14-15. in Ser-I' caudal fin forked~ies) to rounded.. 25

2.4-3.3 in Std.22 gill-rakers; up­line with 28-38>fsal XII-XIVdal fin forked... '..)phthaLmochromls, n~sutus, O. ven­.subspecies: O. ven­-odontus).

~ttea; cneek scally 2~

~t~ ..~~d' .~~;bi~d

canals. withings on head. 21canals with

lings present. 30:hed ray oftwice as longonly 2 lateraldy 22'ay of pelvicse as long to~rnal ray; often1als present. .:. *XenotiLapw

n lower jaw notntally forwards 23.r teeth directedlorizontally for-

.,

179 H.MATTHES

~

yellow-belly).39. - M()uth large; body elongate,

depth 3.b-5.5 times in stan­dard length; -teeth strong,27-52 in outer row of upperjaw *Bathybates(7 species - Banga-banga).

- Mouth moderate; bOOy short,strongly compressed, depth2.7-3.3 times in Std. length;teeth small, 90-110 in upperouter row ........Hemibites(One species: H. stenosoma)

40. _. Mouth horizontal or slightlyoblique; teeth specialised, notsimply conical............... 41

- Mouth nearly vertical; eye verylarge, teeth small and conical. ................ Haplotaxodon(2 species: H. microlopia and H.tricoti).

41. -'Teeth flattened and curvedbackwards.................. 42

-, Teeth unequal. with thick base,. oompressed transversely andwith a small point at the cor­ners of their truncated extre-nilty *Perisoodus(One species: P. microlepis).

42. - 18-26 gill-rakers... *Plecodus(4 species).

- 45-57 gill-rakers ................ *Xenochromis(One species: X. hecqui).

43. - Teeth in external rows all con-ical......... . 44

- External teeth bicuspid andincisor-like anteriorly, conicallaterally, all tricuspid internal-ly; Anal with 4-6 spines .................•.. *Tropheus(2 species: T. moorei and T.duboisi).

44. - All teeth conical. . . . . . . . . . . .. 45- Internal teeth partly tricuspid

18-22 dorsal spines ............. *Telmatochromis(5 species).

45. - Sub-orbital bones ligamentous:21-24 spines and 5-7 soft

rays in Dorsal; brightly andclearly patterned ................ *Julidochromis14 species).

- Sub-orbital bones ossified: Dor­sal 14-21 spines and 6-12soft rays ................. Lamprologus(35 species).

(e) From Lake Victoria

1. - Scales ctenoid............... 2- Scales cycloid Tilapia

This genus has been sub­divided into two main sub­genera distinguished asfollow~:

(a) 7-13 gill-rakers; substratespawners and guarders ofbrood Tilapia Tilapia(2 species: T. (T) rendalli and T.(T) zillii - introduced).(b) 17- 28 gill-rakers; mouthbroodersTilapia Sarotherodon.(4 species: T. (S) esculenta, T.(S) leucosticta - introduced, T.(S) nilotica - introd. and T. (S)variabilis).

2. - Anal fin with 3 spines. . . . .. .. 3- Anal with 4 or more spines....

......... *Astatorheochromis(One species: A. alluaudi).

3. - Teeth in upper jaw in 2 or moreseries anteriorly but in a singlerow posteriorly.............. 4

- Teeth in upper jaw in 2-5series both anteriorly andposteriorly. . . . . . . . . . . . . . . . . . 6

4. - Anterior outer teeth muchlonger than the lateral ones,slender, pointed and directedforwards .. . . . . .. . . . *Paralabidochromis(One species: P. victoriae).

- Anterior outer teeth forming agraded size-series with thelateral ones, not directed for­wards; crown form variable. ; . 5

5. - Tail truncate with rounded cor­ners to emarginate; Anal fin of

male t

(Overendem

- Tail ,withoulight sjposterired tip,

(=Hem(One sprivers).

6. - Outer tlconical;bands aJly .

- Outer telthe crowand poin'* ..

(One spel7. - Lower j

anterioranteriorlJches.....(One spec

- Lower j,tooth bwanteriorl).. ...... ,o ........

(One spec

(d) From el84

1. - 3 spines ~

- Anal witIJ..................(One spec;ly, introdinto POD~trol).

:, 2. - Scales ~

black ..on baBefin .....(Abouting belsewhe

Freshwater Fishes ofTanzania 180

3

4

3

2

5

1. - Adipose dorsal fin, if pJ:'esentsmall .................•.. '"

- Long adipose dorsal fin present. Heterobranchus(One species: H. Longifilis - L.Tanganyika).

2. - Only a long rayed dorsal finpresent .

- A small adipose dorsal fin pre­sent behind rayed dorsal. .................... ·1)inotopterus(One species: 1). cunningtoni _Singa, L. Tanganyika).

3. - Eye dorsal in position, formingno part of head outline whenseen from above .

- Eye latera~ breaking into headoutline when seen from above................ ·Bathyclarias112 species: L. Nyasa).

4. - Pelvic fins considerably closerto end of snout than to base ofcaudal fin; adult size small (upto 30 cm) .

species which have been in­troduced to fish ponds in thecountry).

- Scales ctenoid; adult sizesmall; no spot at base of softdorsaL .

3. - Tail fin truncate with roundedcorners; Anal fin bearing ocelli(egg spots) in male .. Haplochromis

12 species: H. bloyettic, H.strigigena) widespread, incl.Rukwa ---.:: and H. pectoralis _Pangani river).

- Tail well-rounded; Analwithout ocelli, but bearinglight streaky spots posteriorly,often also with an orange tip inthe male .. . . . . . . . .. •Pseudocrenilabrus(One species: P. philander _upper rivers West of L.Rukwa).

IK) FAM: CLARIIDAE

7

2

•

male bearing ocelli (egg-spots)............... ·Haplochromis(Over 180 species, Mostlyendemic).

- Tail well-rounded; Anal finwithout ocelli, but bearinglight streaks or irregular spotsposteriorly, often also with ared tip, in male ............ Pseudocrenilabrus(= Hemihaplochromis)(One species: P. multicolor ­rivers).

6. - Outer teeth small, bicuspid orconical; inner teeth in broadbands anteriorly and posterior-ly .

- Outer teeth enlarged and stout,the crowns obliquely truncatedand pointing inwards .. Macropleurodus(One species: M. bicolor).

7. - Lower jaw stout, roundedanteriorly; teeth groupedanteriorly in 2 pear-shaped pat-ches ·Platytaeniodu~

(One species: P. degeni).- Lower jaw broad and flat;

tooth bands of uniform widthanteriorly and posteriorly...... . . . . . . . . . . . . . . . •Hoplotilapia(One species: H. retrodens).

1. - 3 spines in Anal fin .- Anal with 4 or more spines .

. .. .. . .. . . . . Astatoreochromis(One species: A. alluaudi, wide­ly, introduced as a snail eaterinto ponds for Bilharzia con­trol).

2. - Scales cycloid; adult large;black "Tilapia" spot presenton base of soft part of dorsalfin. . . . . . . . . . . . . . . . . .. Tilapia(About 30 species, several hav­ing been introduced fromelsewhere as well as lake

fd) From elsewhere4

5

6

3

2

akers; substrated guarders of,Tilapia Tilapiar) rendaUi and T.·oduced).ll·rakers; moutha 8arotherodon.(8) esculenta, T.- introduced. T.introd. and T. (8)

;er teeth muchthe lateral ones,~ed and directed

........ Tilapiahas been sub­two main sub­inguished as

3 spines .more spines .

ltatorheochromis4.. alluaudi).: jaw in 2 or morely but in a singlely ··· .)er jaw in 2-5anteriorly and

...............

.. Lamprologus

............... .'aralabidochromisP. victoriae).ir teeth forming aseries with thenot directed for­. form variable. ~ .with rounded cor­pnate; Anal fin of

~ brightly and

~'l~~i~~h'r'~~ is~s ossified: Dor­mes and 6-12

letona

...............

n H.MATTHES

- Pelvics about equidistant bet­ween end of snout and caudalbase; adult size large (over 50cml Clarias (Clarias)(2 species: C. mellandi - L.Nyasa. Rufigi, and C. mossam­bicus . - Kambale. widespreadI.

>. - Sides of head bony. no mediangroo'... e; vertical fins not usual·ly confluent .

- Sides of head soft. coveredwith thick. finely folded skin; amedian longitudinal groove inhead; vertical fins confluent. .............. ·Tanganikallabes(One species: T. mortiauxi - L.Tanganyikal.

6. - Arborescent respiraloryorgans present above gills..... . . . . . . Clarias (Allabenchelys)(4 species: C. carsoni, C.alluaudi, C. theodorae and C.liocephalus, A fifth species, C.hilgendorfi (L. Rukwal hasbeen synonymised. possibly in­correctly. with C. alluaudi).

- No arborescent respiratoryorgans •X enoclarias(2 species: X. ecupogon and X.holobranchus - L. Victoria).

(Ll FAM: SCHILBEIDAE

1. - Small adipose dorsal fin pre-sent .

- No adipose fin Schilbe(One species: S. mystus ­Butter-fish. L. Victoria.Rufigil.

2. - Dorsal fin with/spiny and 5-6branched rays: 9-10 bran­chiostegal rays..... Eutropius(One species: Eutropiusmobiusi -. Eastern rivers).

- Dorsal fin with/supply and on­ly 3-5 branched rays: 8-9branchiostegals. Pareutropius.(One species: P. rnicristius ­Eastern rivers I.

6

2

(Ml FAM: BAGRIDAE

1. - Dorsal fin with 5-6 branchedrays .

- Dorsal with 7-10 branchedrays .

2. - Nasal barbels present; snoutbroad and mouth wide ....................... Bagrus(3 species: one in L. Nyasa (B.meridionalis) one in LakesTanganyika and Victoria (B.docmac) and one in the Easternrivers (B. orientalis).

- Nasal barbels present; snoutnarrow and mouth small .· Auchenoglanis(One species: A. occidentalis -­L. Tanganyika).

3. - Nasal barbels present. .- Nasal barbels absent: .

4. - Caudal fin emarginate to ,fur­cate: adult size over 15 em., ...· Chrysichthys(6 species - L. Tanganyika).

- Caudal fin rounded. adult sizenot exceeding 1'0 em ............... ·Lophiobagrus(One species: L. cyclurus - L.Tanganyika I.

5. - Teeth present on palate;barbels much longer than head;body unspotted dark. .· *Phyllonemus(2 species: P. typus and P.filinemus - L. Tanganyikal.

- No teeth on palate, barbelsshorter than head; body spot-ted Leptoglanis(2 small species: L. rotundicepsand L. brevis).

(Nl FAM: MOCHOKIDAE

1. - Barbels simple. short; mouthenlarged into a sucker-like disc

- Barbels (mandibular) branch­ed; mouth not enlarged into asucker-like disc .

3

2

45

2

U9Tallfull.

2. - Eyedib\aeroover(1 s1rivel

- Eyedibubunc15 c(5 sp,

REF'ERENCE1

Bailey, R. G. (l!E. Afr. agr

Boulenger, G.!reshu'aterMuseum. 4

Copley. H. (l91East A!ric~172p.

Greenwood. P.Kampala, t

Fisheries, Tam:Fi.Divn.

Jackson, P. B. J

NyasaJand3(25 B: 531

Lowe, R. H. (I9fish and IFishery P,

Mann, M. ,r. ('Occ. Pap.- mimeo.

Mann, M. J. IIlist of thOcc. Pap.mimeo.

Matthes, H.ssants d'nals Mu27-88.

Matthes. H.Ruaha I

ecology.Afr· {ref

Poll. M. II!Scient. ,AI: 25

Poll. M. 11Explop.

Poll, M. (Ide I'(Zoo/I,

Poll. M.

.andibular) branch­not enlarged into adisc .

HOKIDAE

lple. short; mouth,0 a sucker-like disc

lent on palate;I longer than head;ted dark .. . . ·Phyllonemus

P. typus and P.L. Tanganyika).n palate. barbelsI head; body spot­· ..... Leptoglanis:ies: L. rotundicepss).

Famil Carcharinidae: Carcharinus zambe.en.,.PTR3., 1852. .

Farn: Pristidae: Pristis microoon LATHAM. 1974.Fam: Dasyatidae: Dasyatis sp.Fam: Elopidae: -Elops machnata FORSK., 1776

(=E. saurusl.Fam: Megalopidae: -Megalops cyprinoides

(BilOUSS, 17821.Fam: Clupeidae: -Pellona ditchelo VAL.. 1847

f=llisha indical.Fam: Engraulidae: -Stolepnorus commersoni

lLAC.• 1803).-S.indicus (VAN HASSELT. 1823).-Thryssa setirostris (BROUSS., 1782).-T. uitrirostris (GILLCHR: and THOMP.,1908).

Fam: Chanidae: -Chanas chana. lFORSK., 1776).Fam: Aridae: Arius africanus GUNTH. and

PLAYF.1866Tachysurus dussumieri IVAL., 1840).

Fam: Piotosidae: -Plotosus arab BLKR.• 1862.Fam: Exocoetidae: -Hemiromphu. fGl' (FORSK.•

17751.

A list of the marine fishes occuring in TanzlJllUl.coastal river.•

Freshwater Fishes ofTanreania 182

This list is limited to only these spec;es which areactually known to penetrate the freshwater lo'lnll'reaches of rivers and doesn't include those whichcommonly enter brackishwater estuaries, etc.Those recorded with certainty from TanzaDia aremarked with an asterisk (.;.

africains, Annis Mus. r. Afr. cent. Ser. 8vo Sci.ZooL, (162): 158 p.

Poll, M. (1971). Revision des Synodontis africains(Famille Mochocidae), Annis Mus. r. Afr. cent. Ser.8uo Sci. ZooL, (191): 497 p.Ricardo. C. K. U9391. The fishes of lake Rukwa. J.Linn. Soc. (Zoo/)., 40 (275): 625-57.Teveme, L. (1972). Osteologie des genres Mo,..

myrus. considerations generales sur lasystematique des poissons de l'ordre des Mor­myriformes, Annis Mus. r. Afr. cent. Ser.8voSc~ ZooL, (200): i94 p.

Thys van den audenaerde. D. F. E. (1968). Anannotated bibliography of Tilopia (Pisces.Cichlidael: Mus. r. Afr. cent. Docum. ZooL. (16):405 p.

Trewf,vas, E. (1964). A revision of the pnuaSerranochromis Regan (Pisces. Cichlidae). An­nis Mus. r. Afr. cent. Ser. 8vo Sci. ZooL (126):58 p.

Trewavas, E. (1973). 1. On the cichlid fishes of thegenus Pelmatochromis with proposal of a newgenus for P. congicus; On the relationshipPelmatochromis and Tilopia and the recogni­tion of Sarotherooon as a distinct genus and11. A new species of cichlid fishes of riversQuanza and Bengo, Angola. with a Ust of theknown Cichlidae of these rivers and a note onPseudocrenilobrus natalensis Fowler. BuLL Sr.Mus. nat. Hist. (Zoo/). 25 ll): 37 p.

APPENDIX l.

.................. Synodontis(19 species of which 9 in L.Tanganyika basin and 2 doubt­ful).

2. - Eye with free border; man­dibular teeth in a long lineacross lower jaw; adult sizeover 15 em Atopochilus(1 species: A. vogti ....,. Basternrivers).

- Eye without free border; man­dibular teeth in a short row orbunched; adult size less than15 em Chiloglanis(5 species).

REF'ERENCES

Bailey, R. G. (1966). The dam fisheries of Tanzania.E. Afr. agric. for. J., 32(1): 1-15.

Boulenger. G. A. (1909-16). Catalogue of thefreshu'ater fishes of Africa, London. Britisl\Museum. 4 vols.

Copley. H. (1958). Common freshwater fishes ofEast Africa, London. H. F. and G. Witherby.172p.

Greenwood. P. H. (1966). The fishes of Uganda,Kampala, Uganda Soc. 131 p. (2nd Edl.

Fisheries. Tanzania (1965-72). Annual reports.Fi. Divn.

Jackson. P. B. N. (1961). Checklist of the fishes ofNyasaland. Occ. Pap. natn. mus. Sth. Rhod.,3(25 B: 535-621).

Lowe, R. H. 11952). Report on the Tilopia and otherfish and Fisheries of Lake Nyasa 1945-47.Fishery Pubis colon. Off.. 1(2): 125 p.

Mann. M..r. (1964). The fisheries of lake Rukwa.Occ. Pap. E. Afr. fresw.Fish. Res. Org. (61.55 P- mimeo.

Mann. M. J. (1968~. A provisional annotated check·list of the freshwater fishes of East Africa.Occ. Pap. E. Afr. freshu.'. Fish Res. Org. 38 p. ­mimeo.

Matthes. H. 119621. Poisons nouveaux ou intere­ssants du Lac Tanganyika et du Ruanda, An·nals Mus. r. Afr. cent. 8uo Ser. ZooL U 11):27-88.

Matthes. H. 11967'. The fishes and fisheries of theRuaha river basin. TanZania, (f.'ystematics.ecology. zoogeography, fisheries I, Dec. Pap. E.Afr. freshu.·. Fish. Res. Org. (91: 19 p.

Poll. M. (1973). Poisons non Cichlldae. Result.Scient. E:rplor. hydrobioL loc Tanganyika, 3 (5A): 251 p.

Poll. M. U9561. Poisons Cichlidae. Result. scient.Explor. hydrobioL lac Tanganyika, 3 (5 BI: 619p.

Poll. M. (19571. Les genres aes poissons deau doucede l'Afrique, Annis Mus. Congo beige ser. 8uo(ZooIJ, 54: 191 p. .

Poll. M. (1967). Revision des Characidae nains

2

45

2

3............ .

present; snoutth wide ......... Bagrusin L. Nyasa (B.one in Lakesnd Victoria (B.te in the Easternltalis).

present; snoutouth small .· . Auchenoglanis4. occidentalis -­Il).I present .i absent: .narginate to Ifur­~e over 15 em, ...· ... ChrysichthysL. Tanganyika).lunded. adult size~ 10 ·cm.. " ... ·LophiobagrusL. cyciurus - L.

AE

5-6 branched

.................

10 branched..............

...".....

183

. Zenarchopterus dispar (VAL., 18461.Fam: Syngnathidae: ·Belonichthys flulJiGtilis

(PTRS., 1852). Syngnathus sp.Fam: Centropomidae: -Ambassis commersoni

CUV., 1828.Fam: Theraponidu: -Therapon jarbuo lFORSK.,

17751.Fam: Kuhliidae: -Kuhlia rupestris (LAC., 18021.

K. taeniura ICUV., 18291.Fam: Carangidae: -Trachynotus falcatus (L., 17661.Fam: Gerridae: Gerres oyena lFORSK., 17751.Fam: Pomadasyidae: Plectrorhynchus grieseus

(VAL., 18601.Fam: Sparidae: Acanthopogrus bema lFORSK.,

17751.

Fam: MonodGctylidu: Psettus arpnteus (L., 17591.P. falciforms (LAC., 180ll.

Fam: MugiUdu -LizG macrokpis (SMITH, 18461.Vaiamu,pl buchGllGlli (BLKR.l.V. seheli (FORSK., 17751.

Fam: Gobiidu: Eleotri butis (HAM-BUCH., 18221.-E. {usCG (BLOCH-8CHN., 180U.-GlossollObius ,puns (HAM-BUCH., 18221.-Gobius hilgendorfj PFEFF., 1896.-Gobius Ip.-Pl4tygobius (Awaous) aeneofuscus (PTRS.,18521.-Ophilocara porocephalo (VAL., 18371.(= Eleotri ophiocephalus).

•

MalViet

ABSTR

Fishlultimat.subjecthistory •populati

The I

Victoriament. Alfish specpopulatilless reIiI

I underutimanagenregulatiotivity inadherenc

INTROD

FishiJlspecies 0

highly reivictorianlesculentato very 10fishing elthe shallfishermenabundant·waters' ~

Presentl~are und,The fisbtrying tothat are

Devel,fiaherieseddficientlong run