.lournal ol the American Ki!hfish Assoc.3 I (1)3-l 7,28-32 (l 998) Miscellaneous Notes on Some Systematic DiffTculties Regarding Old World Cyprinodonts Dr. Jean H. Huber I. Further investigations on the systemotic status of panchar bualanus Ahl, Panchax escherichi Ahl, Haplochilus striatus Boulenger and Aphyosemion striatum micruphtalmum Lambert & Géry. Few cases of discussions have taken place, since Scheel,s remarkable pioneering works (1968 et subseq.), about the systematics and the validity/synonymy status of old Rivulin taxa from the tropical west African forest's gews Aphyosemion. However Scheel was unable to study the ÿpes of most taxa in the various institutions, including those from the Berlin Museum in (the former) East Germany. His conclusions are well known regarding Ahl,s descriptions. Most of Ahl's taxa were considered as synonl,rns of older taxa described by others and even by Ahl himself, e.g. : 1- Panchax elberti Ahl,1924 is ajunior synonym of p. bualanus Ahl, 1924 ; the former taxon being named in a later issue of the same publication (Zoo1. Anz.) than the latter. 2- Panchar escherichiAhl, 1924 (in the same article as elberti) is a junior svnon\r.n of Hctplochilus striatus Boulenger, 1911. Radda. uho did srud\ material at the Berliner Museum on several occasions. drd nor question Scheel's conclusions. We did not either, especialh srnce rie had the opportunity to survey ,,probably,, paraÿpic material ol P c ) -'i;;r.i; hi lrom Z.M.B. (Berliner Zool. Museum) in the mid erghties ^.r :ie latter case and because of distribu_ tional reasons for the fomer c:.: The situation remai::j slable until Seegers' publications of 1986 and 1988. Seegers *as. rrt::'. ::e help and dedication ofthe present Z.M.B. curator Hans-Joachi:t p::i:. the first to stay long periods in Z.M.B. and find out most of _\hls ipe series. study them and pub_ lish major shifts in their systematic srarus. Seegers' major contribution was rvell accepted because ofhis reputatron of seriousness. his record of publicatrons. especially regarding rhe east Aliican genus Nothobranchiit-ç and because the proposed shifts did not hur-t the then accepted validin of the srudied taxa...except in three cases; the two stated above, plus the complicated problem involvingfattca/ walkeri/ deltaense/ kribianurn/ schwoiseri/ gulare, which we will not cover because Aphyosemion fallar Ahl. 1935 has been named from an aquarium population with a questionable origin and the types are said to be lost (nomen vanum). It was not until recently that we were able to find the time to ask to borrow Ah1's ÿpes through the courtesy of our old friendly connaissance H.-J. Pâpke and, to avoid any confusion, we requested the holotype (or the lectoÿpe) which is the single voucher of a species. The purpose ofthese notes is to report on the study ofthese two types and of related material for comparison' l-Panchax bualanus Ahl (holorype and single ÿpe) : ZMB 21947, "Buala, Kamerun, Elbert leg." The subadult specimen is in a desperate condition. The fish is squashed laterally, which makes it higher than in reaiity, most fins are cut neil their base, except the pectorals (which position excludes a relationship with the Aplocheilichthyins), no trace of pigments (especial1y not a single bar on sides) can be found and many scales are lost, including in the lower post-orbital region. There is a iateral, somewhat darker, band on the lower mid sides from the pectoral root to the level of half of the anal base, but this may be seen as the standard lorver median band, present rnthe Kathetys subgenus (and also other subgenera) in formalin preserved or fiightened specimens. Neither the scalation t)'pe. nor the predorsal scale count can be discerned. Due to the lateral squash. man.v scales are lost on the sides. The lateral series count could onll be h1'pothesized as29 (+2 on peduncle), whereas the transrersal series count could be evaluated as 8. lv{easurements : S.L. : l5 l mrn. head length: 6.8 mm (21%in S.L.), predorsal length : l3l nrm (=l0o in S.L.). preanal length: 16.3 mm (659'o in S.L.) All rhese data look reasonable for a non-annual Aphyosention uhich. for biogeographical reasons. belong to the subgenera -lphtosemion, \ Ie s o apln o s ern i on. Kat he^'s. The radrophotograph was more informative : D: 10 ; A: probably 1,.. lD A: -8 :r'ertebrae= 11+16. The skull is of the genus .lphtosemion lpe and the hvpural plate is divided ren linie The abole mentioned data leave little probabiliÿ of it belonring to another senus than .,l.plqosemion i.e. either Epiplatys or.\'r;i;:,i',rtti'lrftis s.l. ; rhe longer dorsal hn base and the somewhal lo.'ie: D.\ deviation rrould favor for the subgenus Katheÿs or -l/e-cr -t-:i.'. 'çention more rhan -4pht'osention s.s. For comparison, two seiies tti specimens belonging to the Paris M.N.H.N. col.ectii"rs have been radiophotographed with the following results MNHN 1978-387 '. Aphyosemioti ii,-;,tritutt sensu Scheel;3 specimens:D:11, 10,9;A:16, 15. 16 :D -{- +1 ,+8, +9;vertebrae- i1+16 : 11-16 : i2+15. ' MNHN 1981-1368 :1. etigttti'it:2 specimens:D:9, l0; A: 15, 15 ;DIA: -1 . -7 ; vefiebrae- 1l-15 ; 12+15. All 5 specimens, with a verl' linle dirided plate, like Ahl's ÿpe' ln conclusion Ahl's rype cannot be distinguished easiiy from the Cameroonian bualanttnt sensu Scheel. Many aspects of morphology, meristics, osteology are similar, however it cannot be ruled out that Ahl's ÿpe belongs to Mesoaphyosemion. The two known Mesoaphyosemion species from the neighboring regions are l. cameronense (D: 12; A= 16; D/A: +6) and A. wildekampi (D:11; A: 16; D/A: +9), but both do not display the verrically barred color pattern disclosed by Ahl for his bualanus, and also present in the Cameroonian bualanum sensu Scheel. It cannot be ruled out also, that following Seegers, A. bualanum is a fasciated, unknown live, Mesoaphyosemion species, which would be isolated in the highlands with distinctive morphomeristics from its neighboring counterpart, either cameronense or more probably wildekampi. It cannot be ruled out finally that Ahl's type is a distinctive Katheÿs species related to the Cameroonian component, but we know ofno geographical barrier in the area and bualanum sensu Scheel is widely distributed on the Plateau. Therefore we feel the probability that Scheel's view is correct is high, (but not 100%) and both names for the Cameroonian populations are then possible... conservatively as bualanum (like in Killi-Data 1996 and according to the ethics of I.C.Z.N.) or following Seegers as elberti, until live topotypes from the mountainous village of Buala, alt. 1200m. (now Bouala : 6.42 N ; 15.58 E) presently in the Central African Republic are collected by keen enthusiastic killie hobbyists or ichthyologists.