Abstract
A new asellote isopod Magnosinosignum duohamus gen. et sp. nov. (Paramunnidae) is reported from southern Australian upper shelf waters. Adult females are about 1.0 mm long (males are not known). The key characters of the new genus are: the fusiforme body shape; pereonites and coxae laterally rounded, without spines; antenna shorter than antennula, with reduced flagellum; mandible without palp, molar club-shaped distally pointed; pereopod 1 ambisubchelate with elongate propodus and short triangular carpus; pleotelson with serrate margins; uropods with protopod and single ramus. The new genus is compared to the Pleurosignum-group, but differs in significant characters. An Appendix provides a list of Australasian Paramunnidae.
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