First record of strict snake eels, Xyrias revulsus Jordan & Snyder, 1901 (Anguilliformes: Ophichthidae), from Vietnamese waters.

Abstract

This paper presents the first record of the strict snake eel, Xyrias revulsus (Jordan & Snyder, 1901), from Vietnamese waters. Eleven specimens were collected at a local fishing port in northern Nha Trang. Xyriasrevulsusis distinguished from its congeners by a combination of the characters: a tail length shorter than the head and trunk (tail length 2.1–2.2 in TL; head length 8.6–9.8 in TL), an acute and short snout (6.0–7.6 in HL), and elongate jaws (upper jaw 2.4–2.5 in HL). The dorsal fin origin is well behind the pectoral fin tip, andthe pectoral fin is moderately developed. Fresh coloration is pale brown with dark brown spots on the dorsal surface above the lateral midline, fading to pale on the ventral surface. The teeth are sharp, needle-like, and slightly recurved on the jaws and vomer. The vertebral count is 17–18 predorsal, 79–81 preanal, and 162–164 total vertebrae (n = 2). This paper provides morphological data, a detailed description, and photographs of the species, thereby extending its distributional range.