Sunday, February 11, 2018

[Ichthyology • 2018] Exostoma sectile • A New Glyptosternine Catfish (Siluriformes: Sisoridae) from Northern Myanmar


Exostoma sectile  Ng & Kottelat. 2018


A new species of sisorid catfish in the genus Exostoma is described from the upper Irrawaddy River drainage in northern Myanmar. The new species can be distinguished from congeners by the condition of the posterior extremity of the adipose-fin base, the degree of tuberculation in the preorbital area, as well as morphometric data for the nasal barbel length, snout length, interorbital distance, adipose fin-base length, body depth at anus, caudal-peduncle length, and caudal-peduncle depth. The taxonomic status of congeners in the Irrawaddy River drainage is also discussed, and E. chaudhurii is revalidated as a distinct species.

Fig. 1. Exostoma sectile, holotype, MHNG 2767.061, 78.2 mm SL. Dorsal, lateral, and ventral views.

Exostoma sectile, new species

Distribution.— This species is known from a single locality near Putao in the upper Irrawaddy River drainage in northern Myanmar.

Etymology.— The specific epithet comes from the Latin adjective sectilis, -is-e, meaning cut or cleft. This is used in reference to the presence of a distinct incision or notch at the posterior extremity of the adipose-fin base in this species. 


Heok Hee Ng and Maurice Kottelat. 2018. A New Glyptosternine Catfish from Northern Myanmar (Teleostei: Siluriformes: Sisoridae). Copeia. 106(1);  63-69. DOI: 10.1643/CI-17-613