Neoleptastacus trisetosus, (Mielke, 1982 a) (Mielke, 1982) Sak et al., 2008

Sak, Serdar, Karaytuğ, Süphan & Huys, Rony, 2024, Review of Neoleptastacus Nicholls, 1945 (Harpacticoida, Arenopontiidae), including an updated key to species and proposal of Phreatipontia gen. nov., Zootaxa 5525 (1), pp. 1-66 : 9

(4) trisetosus -group

Diagnosis. Anal somite without paired dorsolateral processes. Anal operculum well developed, often produced into a rounded medial extension (not illustrated for N. trisetosa ). P1 exp-1 without outer spine (exopod sometimes 2-segmented); exp-3 with three setae/spines. P1 enp-2 with outer spine and inner geniculate seta distally. P2 exp-2 with very long outer setiform element (extending far beyond distal margin of exp-3). Endopod P2–P3 1-segmented. P2 endopod with inner seta and one distal spine. P3 endopod with one distal spine. P4 enp-2 outer seta reduced.

Species included. N. africanus ( Chappuis & Rouch, 1961) , N. trisetosus ( Mielke, 1982a) , N. angolensis ( Bodiou & Colomines, 1986) comb. nov., N. panamensis sp. nov., N. supersetosus sp. nov.

The common origin of the species included in this group is strongly supported by five apomorphic character states: (1) absence of outer spine on P1 exp-1, (2) presence of only three elements on the distal segment of P1 exopod, (3) 1-segmented P2–P3 endopods with reduced armature (110 and 010, respectively), (4) P2 exp-2 with very long outer setiform element, extending far beyond distal margin of exp-3, and (5) anal operculum well developed, often produced into a rounded median extension (unconfirmed for N. trisetosus and N. panamensis sp. nov.). Neoleptastacus africanus and N. angolensis comb. nov. share the plesiomorphic 3-segmented P1 exopod, a distinctly elongate P4 exopod and possibly reduced armature on the P5. Neoleptastacus trisetosus , N. panamensis sp. nov. and N. supersetosus sp. nov. exhibit the apomorphic 2-segmented condition of the P1 exopod. The group has a wide distribution with records from the Galápagos archipelago ( Ecuador), Panama, Kuwait and the Atlantic seaboard of Africa.