Two new species of Paramunnidae (Crustacea, Isopoda, Asellota) from the South Shetland Islands

Abstract

Two new species of Paramunnidae (Crustacea, Isopoda, Asellota) from the South Shetland Islands (sub-Antarctic) are described. Austrosignum escandellae sp. nov. has long eyestalks, dorsum slightly sculpted (transverse bumps on pereonites 1–5), and lateral margins of pereonites rounded. The closest species is A. spinosum Kussakin, 1982 that also shows dorsum sculpted. The main differences are the ocular peduncle (short in A. spinosum) and the lateral margins of pereonites (pointed in A. spinosum). Coulmannia ramosae sp. nov. differs from the other two species of this genus (C. australis Hodgson, 1910 and C. frigida Hodgson, 1910) in that only the margins of pereonites 2–4 are expanded (into one point). A discussion of the Austrosignum/Munnogonium complex is provided with a comparative table of the species involved.

Coulmannia rossensis sp. n. (Isopoda, Asellota, Paramunnidae) from the Ross Sea, Southern Ocean

“…Records from the remaining three species of Coulmannia are scarce: Coulmannia frigida was described by Hodgson (1910) from McMurdo Sound at 229 m depth, and later on reported from the Gauss Station, Wilkes Land at 385 m depth by Vanhöffen (1914) ; Coulmannia ramosae was found only in the South Shetland Island at 89–220 m depth by Castelló (2004a) ; and Coulmannia rossensis is herein reported from the Ross Sea at 196–474 m depth ( Fig. 5 ).…”

“…Thus, sexual dimorphism in Coulmannia frigida remains unknown. Similarly, Castelló (2004a) had only two males when he described Coulmannia ramose ; therefore, the sexual dimorphism in this species is also unknown.…”

“…: Coulmannia australis Hodgson, 1910 from Coulman Island and Coulmannia frigida Hodgson, 1910 from McMurdo Sound. More recently, Castelló (2004a) described the third species of the genus, Coulmannia ramosae Castelló, 2004 from the South Shetland Islands. In the present paper Coulmannia rossensis sp.…”

Revision of Austrosignum Hodgson and Munnogonium George & Strömberg (Paramunnidae) with descriptions of eight new genera and two new species, (Crustacea: Isopoda: Asellota)

“…A. erratum Schultz, 1964Munnogonium, by Georges & Strömberg (1968, tentatively synonymized with Munnogonium tillerae by Wilson (1997) Munnogonium erratum A. escandellae Castelló, 2004 no change…”