Ophichthus naga Psomadakis 2018, sp. nov.

• Main Author: Psomadakis, Peter N.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2018
• Subjects: Biodiversity; Taxonomy; Animalia; Chordata; Actinopterygii; Anguilliformes; Ophichthidae; Ophichthus; Ophichthus naga; Fridtjof Nansen
• Online Access: https://doi.org/10.5281/zenodo.5990975; http://treatment.plazi.org/id/96368788CE6EFF8A52E98A9EFEAFFA28

Ophichthus naga McCosker & Psomadakis sp. nov. New English name: Deepwater demonic snake eel (En) (Figs. 4 – 6) Material examined. Holotype: USNM 438246, 573 mm TL, a gravid female, off the Ayeyarwady Delta, Myanmar (14 o 0 3.73 N, 94 o 19.09 E), R/ V Dr. Fridtjof Nansen , Sta. 68, bottom trawl, 455 – 459 m depth, collected by P. N. Psomadakis. Diagnosis. A moderately elongate species of Ophichthus with: tail 50%, head 11.7%, and body depth at gill opening 0.43% of TL; dorsal-fin origin behind pectoral fin by 2 HL; pectoral fin rounded, not elongate and lanceolate; posterior nostril a hole above upper lip, covered by a flap that extends to edge of mouth; barbels lacking between anterior and posterior nostrils; pores small but conspicuous, SO 1 + 4, IO 5 + 2, POM 6 + 2; upper jaw short, orbit ends above rictus; teeth small, numerous and conical, biserial on upper jaw, uniserial on lower jaw and vomer; coloration dark brown, median fins dark with a pale margin, pectoral fins dark, with a pale ventral margin; vertebral formula 15-65-153. Counts and measurements of the holotype (in mm). Total length 573; head 67; trunk 218; tail 288; predorsal distance 126; pectoral-fin length 19.3; pectoral-fin base 5.0; body depth ca. 25 at gill openings; body width ca. 22 at gill openings; body depth at anus ca. 26.5; body width at anus ca. 23; body depth at branchial basket 26; snout 14.5; tip of snout to rictus 21.5; snout overhang beyond tip of lower jaw 2.3; eye diameter 6.5; interorbital width 8.9; gill opening height 11.5; isthmus width 17. Vertebral formula 15-65-153. Description. Body moderately elongate, stout for an Ophichthus , subcircular to level of anus, then becoming more compressed, its depth at gill openings 23 in TL (Figure 4). Branchial basket moderately expanded. Head 3.3 in trunk. Head and trunk 2.0, head 8.5, and tail 2.0 in TL. Snout short, rounded, moderately acute when viewed from above; upper lip not bisected on underside of snout. Lower jaw included, its tip extending slightly beyond bases of ...