Erebussau, Bezerra & Pape & Hauquier & Vanreusel, 2021

Bezerra, Tania Nara, Pape, Ellen, Hauquier, Freija & Vanreusel, Ann, 2021, Description and distribution of Erebussau nom. nov. pro Erebus Bussau, 1993 nec Erebus Latreille, 1810 with description of a new specie, and of Odetenema gesarae gen. nov., sp. nov. (Nematoda: Desmoscolecida) from nodule-bearing abyssal sediments in the Pacific, Zootaxa 4903 (4), pp. 542-562 : 547

Genus Erebussau nom. nov. pro Erebus Bussau, 1993 nec Erebus Latreille, 1810

Diagnosis: Adapted from Decraemer and Rho (2014). Body cuticle annulated, without ornamentation. Distinct body annulation at the anterior and posterior end. Smooth annules near the anterior end with triangular outline. No lateral differentiation. Cephalic region swollen and offset. Cephalic region and lips thin-walled. Smooth labial surface, labial sensilla not visible. Four cephalic setae with pointed tip. Amphidial fovea vesicular, just posterior to the cephalic region. Stoma small, without teeth; pharynx contour not clear, obscured by the presence of glandular cells. Pigment spots present along the intestine with irregular number, location and shape. Pseudocoelomocytes present. Female reproductive system didelphic, amphidelphic, with reflexed ovaries. Male with two reflexed testes or just the posterior one reflexed. Two round phasmata-like structures, laterally, opposed to each other, on the last posterior third of the tail. Tail conical.

Type species. Erebussau tenebricosus nom. nov., comb. nov.

One other species in genus: Erebussau profundus sp. nov.

Differential diagnosis: Erebussau nom. nov. has a unique appearance when compared with the other genera of the family Meyliidae . It has a distinct body annulation at the anterior and posterior end, without lateral field differentiation as found in Noffsingeria . The peculiar offset cephalic region of Erebussau is unique among the Meyliidae . Pigment spots were not described so far for Meyliidae but they are clearly seen in Erebussau . The presence of phasmata-like structures are also described for the first time within the family Meyliidae .

Etymology: The name is a combination of Erebus (lat.) underworld, referring to the deep-sea habitat of the specimens; and an honor to Dr. Christian Bussau, who first described the genus giving the previous name, Erebus .

Type habitat and distribution: Deep-sea with sediment grain size dominated by silt, containing nodules.

Material examined: 2 ³, 3 ♀ and 4 juveniles from the GSRNOD15–A cruise; 2 ³, 6 ♀ and 2 juveniles from JPI Oceans “Ecological aspects of deep-sea mining cruise” SO239 cruise ; 3 ♀ from Peru Basin , cruise SO242-2 ( Table 1) .