Chaenophryne cf. melanorhabdus

Ho, Hsuan-Ching, Kawai, Toshio & Amaoka, Kunio, 2016, Records of deep-sea anglerfishes (Lophiiformes: Ceratioidei) from Indonesia, with descriptions of three new species, Zootaxa 4121 (3), pp. 267-294 : 291-292

Chaenophryne cf. melanorhabdus [sensu Regan & Trewavas, 1932]

Fig. 21

Material. HUMZ 194463 (1, 91.9), st. 36, 8°40.0'S, 112°29.2'E – 8°40.3'S, 112°27.9'E, off Java, 975–977 m, 20 May 2005. Provisionally identified specimen: HUMZ 194528 (1, 24.2, esca damaged), st. 69, 2°49.4'S, 95°7.0'E – 2°48.6'S, 95°7.4'E, off Sumatra, 400–418 m, 14 Jun. 2005.

Description. Dorsal-fin rays 6; pectoral-fin rays 17; anal-fin rays 5; caudal-fin rays 9. Vomerine teeth 6 (3, 3), upper jaw teeth 34, lower jaw teeth 30. Head length 48.7% SL; head depth 43.9; head width 29.5; illicial length 16.4; upper jaw length 34.3; lower jaw length 46.2.

Body short, globular, slightly compressed, profile rounded in lateral view. No spines on head or on other parts of body associated with cephalic skeleton. Sphenotic with rounded dorsally directed projection. Broad deep groove in inter-frontal space. Mouth large, cleft slightly oblique.

Esca with single simple elongate anterior appendage, pigmented internally except for distal tip, for about onethird of the escal length; pair of blunt anterolateral appendages closely attached to anterior appendage; compressed, posterior appendage, each side connected to lateral appendages to form a concave surface between appendages, with a flap-like crest. Subcutaneous internally pigmented appendage emerging from base of esca and descending along anterior margin of illicial bone.

Body uniformly deep brown to black; illicium pale, covered by semi-transparent skin, internal structure visible externally.

Remarks. The escal morphology of our specimen does not match that of any currently recognized species. The elongate anterior appendage resembles that of C. melanorhabdus Regan & Trewavas, 1932 , but the illicium is shorter than all congeners (16.4% vs. 20.1–47.4% SL in Pietsch, 2009). According to Pietsch (1975), species of Chaenophryne usually have well developed escal appendages and filaments, but these are poorly developed in our specimens, the anterolateral appendages are especially strongly reduced and lack of filaments in all appendages. More specimens may prove the species to be undescribed.

FIGURE 21. Chaenophryne cf. melanorhabdus , HUMZ 194463, 91.9 mm SL, fresh. Illicium is not shown. Family Linophrynidae

Comprising 5 genera and 27 species. One species in Linophryne is recorded among our materials.