Austroleucon levis ( Hale, 1945 )

Gerken, Sarah, 2016, Leuconidae (Crustacea: Cumacea) from the collections of the Museum Victoria, Australia, Zootaxa 4067 (3), pp. 251-292 : 261-262

Austroleucon levis ( Hale, 1945)

Hemileucon levis Hale, 1945: 90 –93, figs. 3–4.

Austroleucon levis .— Watling, 1991: 574 –575, fig. 2.

Material examined. None.

Diagnosis. Female and subadult male. Carapace with strong serrations dorsally on frontal lobe. Antennal notch excavate, without teeth. Pseudorostrum with long and short setae terminally. Pereopod 1 basis more than half length of all other articles together.

Adult male. Carapace with dorsal margin smooth. Pseudorostrum broader and less acute than in female. Antennal notch oblique. Antennal flagellum of 11 articles. Exopods on maxilliped 3 to pereopod 4 with weakly to moderately expanded bases.

Remarks. This species is differentiated from the other two species of Austroleucon by the antennal notch and pereopod 1. In A. levis the antennal notch is excavate and smooth in the female, and pereopod 1 has the basis more than half the length of all the other articles together. In comparison, in both A. adiazetos and A. dolosolevis the basis of pereopod 1 is less than half the length of the other articles together. Additionally, in A. dolosolevis the antennal notch is oblique in both males and females while in A. adiazetos the antennal notch has strong serrations in the female which are absent in A. levis .

In Hale’s (1946) description, the adult males are variable in body size (2.7–3.25 mm), the width of the exopod bases on maxilliped 3 to pereopod 4 (type male, p. 90 fig. D with weakly expanded exopod bases, small male p. 90 fig. F with moderately expanded exopod bases on maxilliped 3 to pereopod 3, weakly expanded exopod basis on pereopod 4), and the dorsal crest, with type male (p. 90 fig. D) and small male (p. 90 fig. F) with the dorsal margin of the carapace smooth, and adult male (p. 90 fig. C) with a serrated dorsal crest as in the female.