Parabathymyrus macrophthalmus Kamohara, 1938

Ho, Hsuan-Ching, Smith, David G. & Shao, Kwang-Tsao, 2015, Notes on the congrid eel genus Parabathymyrus from the western Pacific Ocean, with the description of a new species (Pisces: Anguilliformes: Congridae), Zootaxa 4060 (1), pp. 131-139 : 137-139

Parabathymyrus macrophthalmus Kamohara, 1938

Figs. 3

Parabathymyrus macrophthalmus Kamohara 1938:14 (Mimase, Kochi Prefecture, Japan). Kamohara 1961:2. Masuda et al., 1984:27. Gloerfelt-Tarp & Kailola, 1984:59. Smith, 2000:586.

Material examined (57 specimens, 150–417 mm TL). Taiwan: Off Dong-gang, SW Taiwan: ASIZP 60859 (1, 417), 27 Oct. 2000. ASIZP 65131 (1, 375), 10 Mar. 2005. NMMB-P 1412ex. (1, 280 mm), 6 Feb. 1966. NMMB-P 11170 (1, 351), 15 Dec. 2009. NMMB-P 11175 (1, 367), 16 Jun 2009. NMMB-P 13952 (1, 260), 5 Oct. 2010. NMMB-P 13964 (1, 285), no date. NMMB-P 14122 (1, 280), 14 Jul. 2001. NMMB-P 14212 (1, 260), 20 Oct. 2011. NMMB-P 16366 (1, 387), 23 Feb. 2012. NMMB-P 17866 (1, 380), 25 Jan. 2012. USNM 398561 (1, 339), 14 Nov. 2009. USNM 398562 (1, 330), 14 Nov. 2009. USNM 398563 (1, 385), 14 Nov. 2009. USNM 401021 (1, 398), 26 Feb. 2011. USNM 401069 (3, 337–415), 14 Nov. 2009. USNM 401079 (1, 373), 25 May. 2010. Off Da-xi, Yilan, NE Taiwan: NMMB-P 12230 (1, 364), 22 Jan. 2010. NMMB-P 15565 (1, 400), 23 Oct. 2011. Japan: BSKU 45 (1, 311). BSKU 9983 (1, 339), " Neotype " designated by Kamohara (1961). BSKU 9984 (1, 312). BSKU 79197 (1, 275). BSKU 95489 (1, 405). Vietnam: ASIZP 71614 (2, 252–287), Nha Trang, 16 Apr. 2009. ASIZP 71593 (1, 323), Nha Trang, 15 Apr. 2009. ASIZP 71594 (1, 353), Nha Trang, 16 Apr. 2009. NMMB-P 12324 (1, 297), Da Nang, 9 Apr. 2011. NMMB-P 12328 (1, 226), Da Nang, 9 Apr. 2011. NMMB-P 12332 (1,301), Da Nang, 9 Apr. 2011. NMMB-P 13953 (1, 293), Nha Trang, 18 Apr. 2009. NMMB-P 13954 (1, 294), Da Nang, 9 Apr. 2011. NMMB-P 17924 (1, 267), Phan Thiet, 29 May. 2012. NMMB-P 17926 (8, 231–283), Da Nang, 26 May 2012. USNM 396162 (1, 293), Nha Trang, Apr. 2009. IORAS 3243 (4, 263–386). E. Australia: CSIRO H7419-04 (1, 377), CSIRO H7419-05 (1, 410), CSIRO H7419-06 (1, 380). W. Australia: CSIRO B.3590 (1, 150), CSIRO CA 4011 (1, 308), CSIRO CA 4013 (1, 265). Hainan: IORAS 3244 (1, 280). India: ZSI uncatalogued (1, 246).

Diagnosis. A species of Parabathymyrus with 4 supraorbital pores; head length 5.8–6.8 times in TL; 39–46 preanal vertebrae; 128–137 total vertebrae; 36–44 preanal LL pores; 121–132 total LL pores.

Description. Head length 5.8–6.8 times in TL; body depth at head 12.2–17.5; predorsal 5.0–6.3; preanal 2.4– 2.7; trunk length 3.8–4.7; tail length 1.4–1.7. Snout 5.2–7.8 times in HL; eye 5.0–7.8; interorbital 4.5–8.1; snoutrictus 2.9–3.8; gill opening 4.7–9.5; interbranchial 3.5–7.2; pectoral fin 2.3–4.0. Pectoral-fin rays 12–17.

Body relatively stout, depth of head slightly greater than that of tail; head and trunk cylindrical, gradually compressed to posterior half of body; trunk long; tail moderately long. Origin of dorsal fin above pectoral fin; origin of anal fin slightly anterior to middle of total length (one specimen with the origin far behind the tip of pectoral fin); snout short and obtuse.

Eye relatively large, above posterior half of upper jaw and its posterior margin slightly behind level of rictus; interorbital space broad. Gill opening moderately high, in front of pectoral fin and extended to middle of pectoralfin base. Anterior nostril tube-like, at front of snout; posterior nostril large, just above the upper jaw, and covered by a flap dorsally.

Mouth moderately large, its opening slightly oblique, rictus extending to posterior one-third of orbit; upper jaw protrudes anterior to lower jaw; upper labial flange well developed, extending from anterior nostril to two-thirds of upper-jaw length; lower jaw with a deep fold from tip to rictus; pectoral fin narrow.

Teeth small and villiform, anterior portion of intermaxilla with 4–5 rows of teeth, forming a rounded patch, followed a small triangular patch of teeth on vomer; 4–5 rows anteriorly and gradually narrowing to biserial posteriorly on both jaws. Tongue long, broad and thick, free from the mouth floor.

Vertebrae: predorsal 9–13 (one with 15), preanal 39–46, total 128–137, and MVF 10-43-133. Lateral-line pores moderate in size and complete, prepectoral 5–9, predorsal 6–11 (one with 12), preanal 36–44, and total 121– 132. Head pores: SO 4, IO 5, POM 9–12 (mainly 10–11), ST 0, F 0, AD 0.

Coloration. When fresh, light brown dorsally, lower body paler, lateral-line ossicles white, posterior portion of dorsal and anal fins white and become black at the end; mouth cavity, gill chamber and peritoneum white.

Distribution. Known from the western Pacific off Japan, Taiwan, Hainan, Vietnam, Australia and India. Bathymetric range of specimens collected from Taiwan ca. 100– 300 m.

Remarks. Although this species was previously recorded from Taiwan, we have reidentified these vouchers and all are P. brachyrhynchus . Additional specimens of P. macrophthalmus were found in Taiwanese collections. The holotype of Parabathymyrus macrophthalmus was destroyed in World War II. Kamohara (1961) designated a neotype (BSKU 9983), but this was not done in a revisionary work and is not valid.

One specimen from Taiwan (NMMB-P11170) has a relatively posteriorly situated dorsal-fin origin and 15 predorsal vertebrae (vs. 9–13 in other specimens). We consider it to be anomalous.

Figures

FIGURE 3. Parabathymyrus macrophthalmus Kamohara, 1938. One of USNM specimens examined in present study. Collected from Dong-gang, SW Taiwan.