Monday, January 8, 2018

[Ichthyology • 2018] Amblyceps improcerum • A New Sisoroid Catfish (Siluriformes: Amblycipitidae) from Kachin State, Myanmar

Amblyceps improcerum
 Ng & Kottelat, 2018

A new species of amblycipitid catfish is here described from the Indawgyi Lake basin of the Irrawaddy River drainage in Kachin State, Myanmar as Amblyceps improcerum, new species. It can be distinguished from congeners in having a unique combination of the following characters: lower jaw longer than upper; head length 17.4–22.3% SL; head width 13.7–15.2% SL; head depth 9.0–11.7% SL; interorbital distance 31–39% HL; eye diameter 7–10% HL; 37–38 vertebrae; lateral line incomplete; predorsal length 25.5–30.7% SL; smooth posterior margin of pectoral spine; pectoral-fin length 13.5–16.8% SL; pelvic-fin length 9.6–13.4% SL; dorsal-to-adipose distance 25.2–28.7% SL; length of adipose-fin base 19.4–23.3% SL; adipose fin separate from dorsal procurrent caudal-fin rays; preanal length 62.1–66.9% SL; body depth at anus 9.8–12.8% SL; depth of caudal peduncle 10.1–12.6% SL; length of caudal peduncle 21.4–24.0% SL, post-adipose distance 15.8–17.8% SL; weakly-forked caudal fin with short broadly, rounded lobes (length of longest ray 1.3–1.5 times length of median rays); centrally projecting hooks on proximal lepidotrichia of median caudal-fin rays absent.

Keywords: Ostariophysi, Sisoroidea, Irrawaddy river, New species 

Fig. 1 Amblyceps improcerum, holotype, MHNG 2768.061, 53.2 mm SL; Myanmar: Kachin State: Lake Indawgyi basin. Dorsal, lateral and ventral views

Amblyceps improcerum, new species

Etymology: The specific epithet comes from the Latin adjective improcerus, −a, −um, meaning "not tall" or "undersized", in reference to the relatively short caudalfin lobes and adipose-fin base of this species when compared to nearly all congeners.

Heok Hee Ng and Maurice Kottelat. 2018. Amblyceps improcerum, A New Sisoroid Catfish from Kachin State, Myanmar (Teleostei: Siluriformes: Amblycipitidae). Environmental Biology of Fishes.  DOI: 10.1007/s10641-017-0712-0