Camptocercus uncinatus Smirnov, 1971

Kotov, Alexey A., Jeong, Hyun Gi & Lee, Wonchoel, 2012, Cladocera (Crustacea: Branchiopoda) of the south-east of the Korean Peninsula, with twenty new records for Korea *, Zootaxa 3368, pp. 50-90 : 76-77

15. Camptocercus uncinatus Smirnov, 1971

Fig. 21

Synonymy. Camptocercus uncinatus Smirnov, 1971 , p. 436–438, Figs 128, 532; Smirnov 1998, p. 76–77, Figs 51–57; Kotov et al. 2011a, p. 407.

Camptocercus rectirostris (Schoedler) in Kim 1988, Figs 58–59.

Type locality. "Lake Nikolaevskoe (Chita region)", Russia ( Smirnov 1971, 1998).

Localities in Korea. 6a, 8 (see Fig. 1 and Table 1 ).

Parthenogenetic female. Body ovoid, elongated in lateral view ( Fig. 21 A); strongly compressed laterally and having a well-expressed dorsal keel both on carapace and head. Dorsal margin without depression between valves and head shield, postero-dorsal angle broadly rounded, posterior margin convex, postero-ventral angles broadly rounded. Ventral margin slightly undulated. Rostrum acute, pointed downward ( Fig. 21 B). Three connected main head pores, lateral pores minute. Labrum with a sub-triangular keel; its posterior margin without a denticle, with two groups of fine setules ( Fig. 21 B–C). Row of ventral setae followed by a row of fine setules, in dorsal portion of posterior margin they are strong, denticle-like ( Fig. 21 D–E). Postabdomen very long, narrowing distally, length about 5–6 height ( Fig. 21 F). Preanal portion almost straight, preanal angle well-developed, anal margin almost straight, postanal angle not expressed, postanal margin straight to slifhtly concave; postanal portion 3–4 times longer than anal one. Postanal margin with about 20 clustered postanal denticles with fused bases ( Fig. 21 G). Laterally series of fine setules. Postabdominal claw long, straight, with slightly curved tip; basal spine short, slightly bent, about 0.25 length of claw; few setules at the end of proximal pecten as strong spines ( Fig. 21 G). Antenna I with length about 4–5 width, with three groups of fine setules at anterior face; among nine aesthetascs two longer than the rest, longest aesthetascs as long as antenna I; antennular seta thin, about 1/3 length of antenna I, protruding somewhat distally to middle ( Fig. 21 B). Antenna II short, antennal formula: setae 0-0-3/0-1-3, spines 1- 0-1/0-0-1. Apical setae subequal in size, apical spines very short, spine on proximal exopod segment also very short ( Fig. 21 H). Limb I with ODL bearing a long seta, armed with long setules; IDL with three setae, seta 1 large, well developed, about 1/3 length of ODL seta; setae 2 and 3 thick, curved, hook-like, with a short, setulated distal portion ( Fig. 21 I). Size in our material 0.71–0.80 mm.

Notes. Yoon (2010) recorded only C. rectirostris Schödler, 1862 from Korea but as his illustrations lack denticles on postero-ventral angle of valve, this is not rectirostris , but C. vietnamensis Than, 1980 . We did not see the former in Korea, but found two other species: C. uncinatus Smirnov, 1971 and C. vietnamensis Than, 1980 . Earlier Kim (1988) misidentified C. uncinatus from Korea as C. rectirostris .

According to Smirnov (1998), C. uncinatus is distributed in southern Europe, Israel, Iraq, Egypt, Ethiopia, Rift Valley in Africa, South West Siberia, Central Yakutia and Central America. The American populations most probably belong to a separate species. In general, C. uncinatus occupies the southern Palaearctic. It is recorded from the Amur basin ( Kotov et al. 2011a), where C. rectirostris and C. fennicus Stenroos, 1898 s. lat. are also present. At the same time, its presence in tropical Vietnam, Cambodia and Thailand were put in doubt by Sinev (2011), see next section.

Figures

FIGURE 21. Camptocercus uncinatus Smirnov, 1971, parthenogenetic female from Bak Sil Ji 1, locality 6 a: A, lateral view; B, head; C, labrum; D, armature of postero-ventral valve margin, inner view; E, armature of posterior valve margin, inner view; F, postabdomen; G, postabdominal claw; H, exopod of antenna II; I, distal portion of limb I. Scale bars: 0.1 mm.