Brachiopsilus, Last & Gledhill Csiro, 2009

Last, Peter R. & Gledhill Csiro, Daniel C., 2009, A revision of the Australian handfishes (Lophiiformes: Brachionichthyidae), with descriptions of three new genera and nine new species 2252, Zootaxa 2252 (1), pp. 1-77 : 20

Brachiopsilus gen. nov.

Type species: Brachiopsilus ziebelli sp. nov., by original designation.

Definition. Members of the genus Brachiopsilus are unique among brachionichthyids in having the following combination of features: body relatively deep, 31–43% SL at second dorsal-fin origin; head robust, suboval to slightly compressed in cross section, large, 47–58% SL; caudal peduncle very short, 1–5% SL; illicium short to long and slender (2.2–3.6 in head length), 3–5 times length of esca; skin thick, surface smooth or covered with low, cutaneous ridges, but lacking enlarged, fleshy, wart-like protuberances; no surface scales or protruding spinules apart from sensory scales (deeply embedded scale fragments sometimes present); dermal appendages absent; either body or fins brightly coloured or with a strongly speckled pattern; pectoral-fin rays 9–10 (mainly 9); anal-fin rays 9–10; vertebrae 22–25 (mainly 23 or 24).

Etymology. Combination of the Latin brachium (arm) and Greek psilos (bare or smooth) in allusion to the smooth surfaces of their body and arm-like pectoral fins.

Species. Presently contains three valid nominal species: Brachiopsilus ziebelli sp. nov., B. dianthus sp. nov. and B. dossenus sp. nov. Another form provisionally placed within B. ziebelli needs further investigation to determine its validity.

Remarks. Brachiopsilus is unique among handfishes in having thick, smooth skin lacking warty protuberances (unlike Thymichthys ), protruding spinules (unlike Brachionichthys , Pezichthys , and Sympterichthys ), and dermal appendages. Deeply embedded scale fragments are sometimes present but these are difficult to find without transmitted light and microscopic magnification. Species of Brachiopsilus are high count forms with the highest pectoral-fin counts (i.e. 9–10, only Thymichthys and Sympterichthys have 9 or more), vertebral counts (i.e. shares usually 23 or more with Brachionichthys vs. generally 20–23 in other genera), and second dorsal-fin (i.e. shares usually 17–19 with Brachionichthys vs. generally 17 or fewer in the other genera) and anal-fin (i.e. 9–10 vs. 8–11 in Brachionichthys , 7–9 in Pezichthys and Sympterichthys ) ray counts. Two of the three species are the largest and most robust of all extant handfishes (reaching at least 117 mm SL vs. about 100 mm in Brachionichthys , 46 mm in Pezichthys , 45 mm in Sympterichthys , and 90 mm SL in Thymichthys ). Members of this genus are confined to southern Victoria and Tasmania.