Leucon Kroyer 1846

Leucon Krøyer 1846

Type species. Cuma nasica Krøyer, 1846.

Diagnosis. Female and subadult male. Pseudorostrum projecting anteriorly. Antennule not geniculate. Pereopod 2 ischium present or absent. Uropod endopod biarticulate. Adult male antennal peduncle articles 4–5 with setae only on anterior surface, antennal flagellum extending to mid-pleon. Without penial lobes. With 2 pairs of pleopods.

Remarks. Leucon is a relatively common genus in northern temperate waters, and is depauperate in Australian temperate waters, with the new species recorded here the first record of Leucon in Australian waters. Watling (1991) identified five subgenera within Leucon, and in this paper the two new species of Leucon, from Australia and the Antarctic, are in separate subgenera, diagnosed as follows.

Subgenus Leucon Krøyer, 1846: siphon normal (not elongate), antennule accessory flagellum rudimentary,

pereonite 5 without ventral teeth, and uropod endopod terminal seta not fused to the distal article. Subgenus Alytoleucon Watling, 1991: siphon normal (not elongate), antennule accessory flagellum

rudimentary, pereonite 5 without ventral teeth, uropod endopod terminal seta fused to the distal article. Australian species. Leucon (Alytoleucon) dolichorhinos n. sp.

Antarctic species. Leucon (Leucon) echinolophotos n. sp.