Taxonomy of Finfish (1+2)

4.1.2.14 Family Schilbidae

Characterised by widely separated nostrils, along border of snout, posterior one slit-like with a flap. Barbels elongated , one, two, or four pairs, well developed. Gill openings large. Anal fin very long, free   from caudal fin. This family consists of about 16 genera and 40 species equally divided between Africa and Asia. Asian taxa are restricted to the Indian subcontinent. Much osteological work has been done on the genera of this family. On the basis of the recent findings genera such as Neotriopius, Pseudeutropius have been transferred to Bagridae and Horabagrus to Schilbidae. The phylogeny of the family is in confusion, whether it is polyphyletic or not is yet to be determined. Teugels (1996) opined that a detailed phylogenetic study of the family is absolutely necessary. Much work remains to be done.

Three subfamilies are known. Ailinae ( two genera), Schilbinae (three genera) and Horabagrinae (one genus) a new one erected by me.

Subfamily Schilbinae: Genus Clupisoma : It has now been shown that the genus Proeutropiichthys Hora is a synonym of this genus. Hora (1941) established Proeutropiichthys on the basis of differences in the palate dentition, which he himself agreed  later to be variable. On the basis of examination of about 300 specimens of P. taakree Prof. S . V. Sharma of Nagarjuna University clearly demonstrated that the dentition is not a reliable character and that it overlaps with that of Clupisoma  .species The fusion or separation of the teeth is a function of growth and hence undependable. Roberts & Vidthayanon (1991:101) consider Laides Jordan, 1919 as a senior objective synonym of Proeutropiichtys Hora. Now that Hora’s genus has been merged under  Clupisoma this problem does not arise   Three species are known of the genus Pseudeutropius. P. longipinnis from Burma, P. moolenburghae  and P. brachyopterus from Sumatra. Of these the first one comes under the Indian region, but there is no mention of this species in Day’s Fish India and or any other work. P. acutirostris is a species which is now under Neotropius. As such the genus Pseudeutropius does not occur in the Indian region.

Subfamily: Horabagrinae Jayaram: Characterised by a long anal fin with 23 – 28 rays, large eyes visible fro m below,a dark shoulder spot. Type genus Horabagrus .I proposed (1955) the genus Horabagrus to accommodate Macrones chryseus Day  = Pseudobagrus brachysoma Guenther. .The history of Macrones chryseus itself is a very interesting story. The species was present in ZSI by a single small specimen of Day but with a long anal fin contrary to other Macrones or Mystus species. The locality was stated to be Cochin-China, a lapsus calami  in place of Cochin. When revising the family I collected several specimens from Kerala and proposed the new genus which was confirmed by the BM. However many authors referred the species to Pseudobagrus known from China and Japan. I was able to clearly demonstrate that these genera are distinct from the Indian taxa and thus established Horabagrus. It has already been stated that the genus has been transferred to Schilbidae on the basis of  work done by Tilak, Mo..  De Pinna and  Ferraris(1992) indicated that Mo’s Cladogram  showed Horabagrus  phylogenetically different from Schilbidae. De Pinna (1993) opined that Horabagrus is a reliect sister group of larger Siluriform clade and fit to be in a separate family. Further work is needed to confirm this however I have placed  the genus under a subfamily for the present.