Oradarea Walker 1903

Oradarea Walker, 1903 Oradarea Walker, 1903: 56. —J.L. Barnard, 1969: 178 (in part). — Thurston, 1972: 34. —J.L. Barnard & Karaman, 1991: 330 (in part). — Bousfield & Hendrycks, 1997: 49 (in part). — Lowry & Myers, 2013: 39 (in part) — Horton et al., 2025 (in part). Type species. Oradarea walkeri Shoemaker, 1930, monotypy. Emended diagnosis. Body slender, weakly compressed laterally, integument usually with scales; posterodorsal margin of pereonite 7 often projected, posterodorsal margins of pleonites 1, 2 usually projected. Head with anteroventral corner acutely or slightly produced, rostrum distinct. Antennae long, slender, flagella lacking calceoli; antenna 1 peduncular articles usually progressively shorter, accessory flagellum 1-articulate; antenna 2 longer than antenna 1. Mandible, molar triturative, columnar; palp article 2 longer than article 3. Lower lip lacking inner lobes. Maxilla 1, inner plate with many medial setae, outer plate with many robust setae distally; palp article 1 shorter than article 2, article 2 bearing distal robust setae. Maxilla 2, inner plate ca. 0.9–1.5 times width of outer plate; inner plate with facial row of many setae and medial setae, outer plate bearing distal setae. Coxae medium length; coxa 1 with anterodistal corner rounded, coxa 4 excavated posteroproximally, coxae 5, 6 bilobed. Gnathopod 1 short, subchelate; propodus longer than or as long as carpus, palm oblique. Gnathopod 2 much longer than gnathopod 1, subchelate, sexual dimorphism indistinct; carpus and propodus elongate, with many short posterior setae, propodus longer than carpus, palm oblique, dactylus short. Pereopods 3–7 slender, dactyli smooth or with a minute projection on inner margins, bases of pereopods 5–7 lobate. Epimeral plates 1–3, posteroventral corners more or less produced. Uropods 1–3 progressively shorter, outer rami shorter than inner rami, both rami usually with dorsolateral and dorsomedial robust setae. Telson longer than wide, generally entire, but rarely incised slightly; distal margin rounded, subacute or truncated. Included species (15 species). Oradarea acuminata Thurston, 1972; O. bidentata K.H. Barnard, 1932; O. crenelata Alonso de Pina,1995; O.dawa Lowry&Myers, 2003; O.edentata K.H. Barnard,1932; O.impressicauda K. H. Barnard, 1932; O. novaezealandiae (Thomson, 1879); O. ocellata Thurston, 1972; O. rossi Thurston, 1972; O. shoemakeri Pirlot, 1934; O. surera Alonso, 2012; O. tricarinata K.H. Barnard, 1932; O. tridentata K.H. Barnard, 1932; O. unidentata Thurston, 1972; and O. walkeri Shoemaker, 1930. Remarks. J.L. Barnard & Karaman (1991) and the World Register of Marine Species (WoRMS) database (Horton et al. 2025) both include O. megalops (Nicholls, 1938) in the genus; however, this species does not belong to Oradarea but instead to Atylopsis Stebbing, 1888 because of the shorter gnathopod 2 and the emarginate telson (Thurston 1972, Rauschert 1989). In O. shoemakeri, morphological characters of the male specimen from another locality (Sulawesi) quite differ from those of the female type (Pirlot 1934), and the male specimen should be transferred to another genus probably in the family Amathillopsidae Pirlot, 1934. In addition, in three Oradarea species including O. bidentata, O. impressicauda, and O. tricarinata, the lower lip has not been described (K.H. Barnard 1932); re-examination of these species is required. Distribution. Only in the Southern Hemisphere: mainly Antarctica (Thurston 1972); Argentina (Alonso 2012), New Zealand (Thomson 1879), New Caledonia (Lowry & Myers 2003), and Timor (Pirlot 1934). Depth range: 0– 525 m.