The generic status and affinities of Paratilapia thomasi Blgr 1915 (Teleostei, Cichlidae) Peter Humphry Greenwood Department of Zoology, British Museum (Natural History), Cromwell Road, London SW7 5BD Contents Introduction and synopsis 257 Materials 258 Anomalochromis gen. nov 259 Notes on the osteology and anatomy of Anomalochromis thomasi Osteology 260 Anatomy 268 The relationships of A. thomasi 269 Acknowledgements 271 References 271 Introduction and synopsis When originally described (Boulenger, 1915), the species thomasi was placed in the genus Paratilapia Bleeker, 1868, then a large, catch-all assemblage of African Cichlidae. The artifi-ciality of Paratilapia (sensu Boulenger) was recognized by Regan in his classical series of papers on the generic classification of African cichlid fishes, the first explicitly 'natural' classification of the group attempted (Regan, 1920: 34). Regan (1922: 252) considered Paratilapia thomasi to be a member of the genus Pelmatochromis Steindachner, 1894. Regan's definition of that genus was based largely on osteological and dental features, most of which were present in P. thomasi, but some of which could not be checked because no skeletal material was available, as for example, the nature of the apophysis on the third vertebra, and the number of vertebrae. That Regan's concept of Pelmatochromis embraced a polyphyletic taxon was recognized by Thys van den Audenaerde (1968:373), who in revising it, took into account features of soft anatomy as well as osteological characters, and certain ethological and other biological features such as coloration. Pelmatochromis thomasi, however, proved to be something of a stumbling block since neither alone nor in combination did its various characters qualify it for inclusion in any of the informal divisions into which Thys van den Audenaerde split Regan's Pelmatochromis. According to Thys van den Audenaerde (1968: 382), P. thomasi shows greatest affinity with Hemichromis bimaculatus. He did not, however, transfer the species to that genus, and nomen-claturally at least it remained in Pelmatochromis, even after Trewavas (1973) formally redefined that genus and excluded thomasi from it (Trewavas, op cit.\ 14). Most recently, Wilson & Loiselle (1980) placed P. thomasi in the genus Hemichromis. Their reasons for so doing are that, as a result of Loiselle's (1978) revision of Hemichromis, P. thomasi could not be excluded on the basis of its dentition, and that its breeding biology and live coloration also argued ' . . cogently for regarding this species as a specialized dwarf Hemichromis '. Bull. Br. Mm. not. Hist. (Zool.) 49 (2): 257-272 Issued 1 9 December 1 985
BioStor
