Comprehensive DescriptionRead full entry
Diagnosis: No thoracic adhesive apparatus; granulate anterior margin on pectoral spine; slender body shape; smooth to granulate anterior margin on dorsal spine; papillate upper lip; moderate gill openings; 13-16 anal rays.
Ayarnangra ZBK is distinguished from all other erethistid genera by having 13-16 anal fin rays (vs. 8-12) and a granulate (vs. serrated) anterior margin on the pectoral spine. It is further distinguished from Conta ZBK , Pseudolaguvia ZBK and Caelatoglanis ZBK by the absence of a thoracic adhesive apparatus, from Caelatoglanis ZBK by having a papillate (vs. plicate) upper lip, from Caelatoglanis ZBK and Erethistes by having a more slender body (Fig. 2), from Caelatoglanis ZBK and Pseudolaguvia ZBK by having moderate gill openings (vs. wide, nearly meeting one another on the venter), and from Conta ZBK by having a granulate (vs. serrated) anterior margin on the dorsal spine and moderate gill openings (vs. extremely narrow gill openings not extending onto venter).
TABLE 2. External traits diagnostic for genera of Erethistidae
|Conta ZBK||Pseudolaguvia ZBK||Caelatoglanis ZBK|
|Adhesive apparatus on thorax||Long; extends nearly to pelvic fin base||Short; not reaching nearly to pelvic fin base; with median depression||Short; not reaching nearly to pelvic fin base; without median depression|
|Gill openings||Extremely narrow; restricted to pectoral fin base||Wide; nearly meet one another on venter||Wide; nearly meet one another on venter|
|Anterior margin of pectoral spine||Serrations all directed toward tip of spine||Serrations all directed toward tip of spine||Serrations all directed toward tip of spine|
|Anterior margin of dorsal spine||Serrated||Smooth to granulate||Smooth to granulate|
|Body shape||Elongate (Fig. 4)||Elongate (Fig. 8)||Moderately elongate (Fig. 3)|
|Anal fin rays||9-10||8-10||8-10|
|Erethistes||Erethistoides ZBK||Ayarnangra ZBK|
|Adhesive apparatus on thorax||Absent||Absent||Absent|
|Gill openings||Moderate; extend onto venter||Moderate; extend onto venter||Moderate; extend onto venter|
|Anterior margin of pectoral spine||Serrations point toward tip, arranged in divergent pairs, or outwardly directed and not divergent (Fig. 6a & b)||Serrations directed toward tip of spine distally and away proximally (Fig. 6c)||Granulate|
|Anterior margin of dorsal spine||Smooth to granulate||Smooth to granulate||Smooth to granulate|
|Body shape||Robust (Fig. 5)||Elongate (Fig. 7)||Elongate (Fig. 2)|
|Anal fin rays||8-12||9-11||13-16|
Description: Dorsal fin with 1 spine, 6 rays; pectoral fin with 1 spine, 5-6 rays; 6 pelvic-fin rays, 13-16 anal-fin rays, first 7-8 rays simple; 16 principal caudal rays. Body elongate. Eyes very small, nostrils huge, much larger than eye. Palatal teeth absent. Maxillary barbel with well-developed membrane, soft base; extending slightly beyond pectoral-fin spine origin. Bases of outer and inner mental barbels nearly parallel. Gill openings moderate; branchiostegal membranes broadly fused to isthmus. Pectoral girdle with large coracoid process externally visible. Pectoral-fin spine with finely granulated anterior edge, serrated posterior edge. Dorsal spine granulated anteriorly, with small serrations posteriorly. No thoracic adhesive apparatus. Paired fins non-plaited.
Distribution: Irrawaddy River drainage, Myanmar (Roberts, 2001).