Thermoarcturus Paul & Menzies, 1971

Poore, Gary C. B., 2015, Thermoarcturidae, a new crustacean family of three genera (Isopoda: Valvifera), Zootaxa 4007 (3), pp. 409-418 : 414

Thermoarcturus Paul & Menzies, 1971

Thermoarcturus Paul & Menzies, 1971: 33 .— Kensley & Schotte 1989: 255.

Type species. Thermoarcturus venezuelensis Paul & Menzies, 1971 , by original designation and monotypy.

Diagnosis. Head and pereonites 2–4 with simple sublateral spines, pleotelson scarcely ornamented; pereonites 5–7 and anterior pleon scarcely armed; pleotelson with minute lateral wings. Eyes present. Male pleopod 1 exopod with well defined groove opening at end of rounded lobe, with prominent ventral ridge-tooth mesially. Oostegites 5 apparent as pair of small ovoids covering oopores.

Remarks. Abundant material of both sexes of the type species enables the genus to be diagnosed more precisely and for it to become the type of the new family. Paul & Menzies’ (1971) stated that pereonite 1 was free from the cephalon, but this is wrong and is never the case in arcturoid valviferans, and that the pleon is composed of three free somites. This too is not so and their crude drawing does not suggest it; a strong dorsal groove distinguishes pleonite 1 from the remainder of the pleotelson but without allowing any articulation.