Saturday, November 4, 2023

[Ichthyology • 2023] Mystus celator • A New Species of Catfish (Siluriformes: Bagridae) from northern Myanmar

 

 Mystus celator
Ng & Kottelat, 2023


Abstract
Mystus celator sp. nov. is described from the Irrawaddy River drainage in northern Myanmar. It can be distinguished from congeners in having a combination of: three equally dark longitudinal stripes separated by two pale interspaces on sides of body; round, dark tympanic spot; ovoid, dark spot on caudal peduncle; length of adipose-fin base 18.0–23.3% SL; angle of predorsal profile 21–24°; posterior cranial fontanelle not reaching base of supraoccipital process; 25–30 rakers on the first branchial arch; and 35–36 vertebrae. The identity of Mystus pulcher is fixed with the designation of a lectotype.

Key words: Freshwater fishes, Irrawaddy River, Teleostei

 Mystus celator sp. nov., MHNG 2790.082, holotype, 80.6 mm SL;
Myanmar: Thein Lin Chaung at Thein Lin village.
Dorsal, lateral and ventral views.

Mystus celator sp. nov.
 
Diagnosis: Mystus celator sp. nov. is distinguished from congeners except for M. pulcher and M. rufescens in having a combination of three equally dark longitudinal stripes separated by pale interspaces on the sides of the body, a round, dark tympanic spot, and an ovoid, dark spot on the caudal peduncle (vs. at least one of these three features absent; Table 1). It differs from M. pulcher and M. rufescens in having a shorter adipose-fin base (18.0–23.3% SL vs. 27.5–49.1), with the following combination of characters further distinguishing it from congeners: angle between body axis and predorsal profile 21–24°, posterior cranial fontanel not reaching base of supraoccipital process, 25–30 rakers on the first branchial arch, and 35–36 vertebrae.

Etymology: The specific name comes from the Latin noun celator, meaning a concealer or hider, and is used in allusion to its close similarity to (and misidentification with) M. pulcher.


Heok Hee Ng and Maurice Kottelat. 2023. Mystus celator, A New Species of Catfish from northern Myanmar (Actinopterygii: Siluriformes: Bagridae). Vertebrate Zoology. 73: 981-990. DOI: 10.3897/vz.73.e110875