Sinodiaptomus sarsi ( Rylov, 1923 )

Svetlichny, L. & Samchyshyna, L., 2021, A New Finding Of The Non-Native Copepod Sinodiaptomus Sarsi (Copepoda, Calanoida, Diaptomidae) In Ukraine, Zoodiversity 55 (1), pp. 1-8 : 3

Sinodiaptomus sarsi ( Rylov, 1923)

R e d e s c r i p t i o n. Female ( FIg. 1 , A). Body length (excluding furcal setae) 2.05–2.49 mm (2.24 ± 0.13 mm, n = 15), prosome length 1.45–1.75 mm (1.58 ± 0.09 mm), prosome width 0.51 – 0.65 mm (0.58 ± 0.04 mm). The dorsal surface of last prosomal somite with a chitinous, triangular projection ( FIg. 1 , A), which is a diagnostic character of the genus Sinodiaptomus ( Kiefer, 1932) . This somite with moderately developed wings. Left wing twolobed with inner one round. Right wing relatively pointed. Both lobes with strong hyaline spine ( FIg. 2 ). Urosome with three somites, genital somite slightly asymmetrical, with a moderately long hyaline spine on each side, the intermediate somite short. Antennules extending beyond the caudal setae ( FIg. 1 , A). Сoxopodite of leg 5 with long, strong, distolateral projection ( FIg. 3 , arrow).

Male ( FIg. 1 , B). Body length 1.9–1.95 mm (1.91 ± 0.02 mm, n = 20), prosome length 1.20–1.32 mm (1.25 ± 0.04 mm), prosome width 0.45–0.48 mm (0.46 ± 0.02 mm). Urosome has a lateral bend to the right. Antennules reach the end of caudal rami. Right antennule geniculated between segments 18 and 19; segment 15 ( FIg. 4 ) with longer projection than that of segment 14; antepenultimate segment of right male antennule with a comb-like process ( FIg. 4 ). Basipodite of right leg 5 with a wide round process reaching almost the distal end of the exopodite I and with a hyaline lamella on its distal inner margin ( FIg. 5 ). Exopodite II of left leg 5 ending in a lamellate thumb-like process with short posterodistal basal projection.

Figures

Figs 1–5. Sinodiaptomus sarsi: 1 — habitus of female (A) and male (B); 2 — last prosomal somite and urosome of female; 3 — leg 5, female; 4 — right antennule, male; 5 — leg 5, male.