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

Van Quang Vo; Thi Thu Thao Le; Cong Thinh Tran; Quang Nghi Bui; Huans Ching Ho

doi:10.15625/1859-3097/23910

Author affiliations

Authors

Van Quang Vo Institute of Oceanography, VAST, Vietnam https://orcid.org/0000-0002-9680-6898
Thi Thu Thao Le Institute of Oceanography, VAST, Vietnam https://orcid.org/0000-0002-9985-4668
Cong Thinh Tran Institute of Oceanography, VAST, Vietnam https://orcid.org/0009-0009-2588-9081
Quang Nghi Bui Institute of Oceanography, VAST, Vietnam https://orcid.org/0009-0001-8135-5473
Huans Ching Ho Graduate Institute and Department of Aquaculture, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan; National Museum of Marine Biology & Aquarium, Pingtung, Taiwan; Australia Museum, Sydney, New South Wales, Australia

DOI:

https://doi.org/10.15625/1859-3097/23910

Keywords:

Taxonomy, morphometrics, range, East Sea of Vietnam

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. Xyrias revulsus is 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, and the 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.

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