Dorsiceratus Drzycimski, 1967

Genus: Dorsiceratus Drzycimski, 1967

Type species.

Dorsiceratus octocornis Drzycimski, 1967 .

Additional species.

Do. andeep sp. nov., Do. denizae sp. nov., Do. dinah George & Plum, 2009 , Do. karinae sp. nov., Do. triarticulatus Coull, 1973 , Do. ursulae George, 2006 , Do. wilhelminae George & Plum, 2009 .

Generic diagnosis

(emended from George and Plum 2009): Cletodidae T. Scott, 1905 ; Cletodinae T. Scott, 1905 ; Ceratonotus group sensu Conroy-Dalton (2001). Body long, slender, ranging from 360 µm to 799 µm. Cphth frontally with strongly developed “ peak ”, lacking pronounced frontolateral horns ( FLH) but carrying anterior cephalothoracic setular tufts (ACST). Moreover, the lateral sides of the cphth are extended strongly in ventral direction ( CLVEa). Rostrum constricted, fused to cphth, square or rectangular, sometimes more or less pronouncedly cleft at its tip, terminally with pair of sensilla and single tube pore (not documented for all species). Cphth and P 2 – P 4 - bearing thoracic somites dorsally with pair of spinulose cuticular processes at their distal margins, which bear single sensilla at their bases and tips (CLDP and DP 1 – DP 3, respectively). Thoracic somites bearing P 2 – P 5 with dorsal single tube pores, laterally with setular tufts ( TST 1 – TST 4). Genital double-somite present in female, dorsally with suture indicating former separation, anterior part (as well as P 6 - bering somite in male) dorsally with tube pore and with lateral setular tuft ( GST). Abdominal part of GDS (likewise first abdominal male somite) and following abdominal somite also with lateral setular tufts ( AST 1, AST 2). Last thoracic somite and abdominal somites dorsally without or with tube pores in differing numbers. Telson broader than long, trapezoidal in dorsal view. Anal operculum with row of spinules. FR of variable length, with 6–7 setae (I / II – VII), terminally with or without tube pore, furcal seta I minute or completely lost. Female A 1 4 - segmented, male A 1 (5 –?) 6 - segmented, haplo- or chirocer. A 2 with allobasis bearing 2 abexopodal setae, exopod completely reduced. Md with variable gnathobase and 1 - segmented palpus bearing 4–5 setae: 1 basal, 2–3 endopodal, and 1 exopodal seta. Mxl with coxa and basis distinct or fused. Mx with 2 endites, each with 2–3 setae, syncoxa and basis distinct or fused; endopod absorbed into basis, represented by 2 setae, or if distinct, then small and carrying 2 setae. Mxp prehensile, syncoxa terminally with 1 seta, endopod produced into long claw accompanied by minute seta. Swimming legs 1–4 with transversely elongate bases and with exo- and endopod. P 1 exopod 2–3 - segmented; if 2 - segmented, then exopodal outer spine of former exp 2 arising at its original position or located subapically in terminal segment; thus, terminal segment with 4 or 5 (geniculate) setae. P 1 endopod not prehensile, 2 - segmented, enp 2 terminally with 2 setae. P 2 – P 4 with 3 - segmented exopods and 2 - segmented endopods, enp 1 much shorter than enp 2. P 2 exp 3 invariably with tube pore. Female endopodal segments P 2 – P 4 with 1-2 - 2 apical setae, respectively. Male P 2 endopod as in the female; P 3 endopod 3 - segmented, with outwardly curved apophysis on inner edge of enp 2 and with 2 apical setae on enp 3. Male P 4 enp 2 with 2 apical setae and 1 outer spine. P 5 with basoendopod whose endopodal part is completely absorbed by the basis and represented by 0–2 setae that may be accompanied by 0–2 tube pores; outer basal seta arising from small setophore and accompanied by long tube pore; exopod distinct or fused to basoendopod, with 5 setae, 1 long tube pore may be present subterminally.