Barathronus pacificus Nielsen & Eagle, 1974

Nielsen, Jørgen G., Pogonoski, John J. & Appleyard, Sharon A., 2019, Aphyonid-clade species of Australia (Teleostei, Bythitidae) with four species new to Australian waters and a new species of Barathronus, Zootaxa 4564 (2), pp. 554-572 : 565-566

Barathronus pacificus Nielsen & Eagle, 1974

Table 1, Figs. 1 , 9–10

Barathronus pacificus Nielsen & Eagle, 1974: 1067 (type locality: 44°41.1’N, 133°24.1’W).

Barathronus pacificus: Nielsen et al. 1999: 139 .

Material examined. (2 specimens, 86–95 mm SL): CSIRO H 8092-03, male, 86 mm SL, GAB, SA, 35°42.95’S, 131°39.38’E, RV Investigator , st. IN2017_C01/178, beam trawl, 3817–3950 m, 16 Apr. 2017. CSIRO H 8093-01 (GenBank Accession MH 491987 ; head badly damaged during capture), male, 95 mm SL, GAB, SA, 35°48.86’S, 131°42.16’E, RV Investigator , st. IN2017_C01/179, beam trawl, 4618–4750 m, 17 Apr. 2017 .

Size. Largest known specimen is a ripe female 140 mm SL.

Diagnosis. Barathronus pacificus differs from the other nine Barathronus species by the following combination of characters: Dorsal fin rays 67–80, anal fin rays 61–69, pectoral fin rays 25–27, precaudal vertebrae 37–39, total vertebrae 82–89, anterior gill arch with 28–35 long rakers, 6–8 fangs on vomer, peritoneum transparent, no ventral flexure of anteriormost vertebrae and a pair of small claspers at basis of penis.

Distribution ( Fig. 1 ). Six earlier known specimens from nearby localities in the NE Pacific at 3334–3860 m, from a 42 mm SL juvenile from the Tasman Sea and now from two GAB stations in close proximity at 3817–4750 m.

Remarks. The present two specimens are compared to the six earlier known specimens, including the type material from the Northeast Pacific. Table 1 shows just a few minor differences between the specimens from the two areas. Also included in the table is a 42 mm SL pelagic juvenile of B. pacificus recorded by Okiyama & Kato (1997) from the Tasman Sea between Lord Howe and Norfolk Islands (30°00’S, 163°00’E) which was not part of the Australian Exclusive Economic Zone in 1997. It was therefore not included by Bray et al. (2015) in their summary of the Aphyonidae .

Figures

FIGURE 1. Records of aphyonid-clade species in Australian waters including the non-Australian paratypes of Barathronus algrahami n. sp. Some symbols represent more than one specimen (Image © NASA, TerraMetrics, Google Earth).

FIGURE 9. Barathronus pacificus, OS 12519, 96 mm SL, female (37°43.2’N, 127°28.9’W) (Image: Marcus Krag).

FIGURE 10. Right otolith from Barathronus pacificus, CSIRO H 8093-01, 95 mm SL: A—inner face, B—ventral view.