Diagnosis. Antenna 1: peduncular article 1 with dorsodistal flange partially overlapping article 2 and produced medially to form an operculum; without accessory flagellum. Mandibles: left incisor with 4-5 teeth; left lacinia mobilis with 4 teeth; left accessory setal row with 3-4 broad robust setae and 0-3 intermediate plumose setAe; right incisor with 4-5 teeth; right lacinia mobilis with 1 large tooth and a minutely denticulate margin; right accessory setal row with 2 robust setae and 2 plum9Se svtae; mandibular palp short, broad. Maxilla 1: outer plates each with 7-10 setal-teeth. Gnathopod 2: carpochelate in male, subchelate in female. Peraeopods 3 to 7: dactyli all directed posteriorly. Peraeopod 4: merus short, not expanded posteriorly. Peraeopod 5: coxa in femqle subequal or larger than in male, without fringe of long setae; dactylus with large unguis and 1-2 small accessory spines. Peraeopod 6: dactylus with large unguis and 2 small accessory spines. Peraeopod 7: dactylus with large unguis and 1-2 small accessory spines. Pleopod 2: inner ramus reduced, 1 articulate or pleopod uniramous. Pleopod 3: one reduced I-articulate ramus or pleopod absent. Uropod 2 with one ramus. Uropod 3 with one vestigial ramus bearing small recurved spines.
Type species. Notopoma stoddartae n.sp.
Species compositipn. Notopoma currently contains 10 species: N. africana n.sp.; N. crassicornis (Bate, 1857); N. fallohidea (Lowry, 1981); N. harfoota (Lowry, 1981); N. lutkini (Tzvetkova, 1990); N. moorea n.sp.; N. opposita (K.H.' Barnard, 1931); N. sismithi (Stebbing, 1888) ; N. stoddartae n.sp. and N. stoora (Lowry, 1981). Etymology. The name Notopoma is derived from the Greek "poma" for lid and refers to the peduncle of antenna 1 which forms a lid to seal the tube, and "noto" for southern which refers to the distribution of the genus.
Remarks. Notopoma differs from Bathypoma in having a carpochelate gnathopod 2 in the male and from all other genera in the Cerapus clade in having an expanded peduncular article 1 on antenna 1. Sars (1894) observed that the peduncular articles function as an operculum in N. crassicornis.We have seen this phenomenon a number of times in preserved specimens still in their tubes. Apparently the antenna geniculates strongly between peduncular articles 1 and 2 so that the distal end of the antenna folds back into the tube leaving the dorsal surfaces of the first peduncular articles to form a cap which closes the tube.