Diagnosis |
This species is distinguished by the following set of characters: the dorsal surface of disc is brown purplish with no distinct ocelli or blotches margined with dark brown on pectoral and pelvic fins; the upper surface of the disc smooth except few small spinules scattered on tip of snout; presence of ocular thorns and absence of scapular thorns; single nuchal thorn may be either present or absent; one median row of 10 to 24 small caudal thorns; the dorsal and caudal fins scattered with very few spinules; 1-2 interdorsal thorns; tail relatively long and thin, approximately half the total length; ventral surface of disc as dark as the upper side, smooth except few small spinules scattered on tip of snout; interbranchial space with no prickles (Ref. 79571).
Description: disc rhombic; snout greatly elongated; anterior margin of disc concave and posterior margin convex with rounded inner corner to level of pelvic fins; the tail is very slender and relatively long with a thin lateral tail fold; nostril flaps short, thick and tube-like; anterior nasal flap (nasal curtain) is well developed and fringed along distal margin; posterior nasal flap is poorly developed and smooth; mouth slightly arched; dorsal side of disc smooth except with a few small spinules scattered on tip of snout (one specimen with spinules also placed on both sides of eyes as well as in front of ocular region); the ventral side of disc, pelvics, claspers and tail are without dermal denticles except with a few small spinules scattered on tip of snout; midline of tail with 13 (10-24) small thorns, with oval bases and backwardly directed crowns. Coloration when fresh: upper surface of the disc plain purplish brown and margined with dark brown on pectoral and pelvic fins with no distinct ocelli or blotches; thorns are marked off pale milky-white pigment; lateral tail folds are creamy white pigment; dorsal fins are uniformly brown (Ref. 79571). |