Key for identification of Cladocera of the subfamily Aloninae (Anomopoda: Chydoridae) from South-East Asia Author Sinev, Artem Y. text Zootaxa 2016 4200 4 451 486 journal article 10.11646/zootaxa.4200.4.1 385be9e3-2309-4de5-9bff-80f724cf4892 1175-5326 191528 5DF1767F-71A9-451F-A418-D1D47A853586 Leydigia Kurz, 1875 Parthenogenetic female short description. Body high, egg-shaped ( Fig. 12 E); maximum height at third fourth of the body; head and valves without keel. Valves without sculpture. Posteroventral angle of valves without denticles. Rostrum short. Three main head pores with a narrow connection between them; lateral head pores minute. Labral keel wide, with rounded apex, without clusters of setulae on posterior margin; unlike in all other genera, its anterior margin covered by dense thin setulae. Postabdomen ( Fig. 12 F) very large, broad, with convex postanal margin, convex distal margin and broadly rounded distal angle; length about 2.5 heights. Preanal and postanal angle weakly defined. Postanal denticles minute, in clusters. Lateral groups of setulae in distal half of postanal portion with extremely long and thick distalmost seta, with length about 3–4 widths of base of postabdominal claw. Postabdominal claw long, almost straight, with rudimentary basal spine. Antennule with nine terminal aesthetascs of similar length. Antennal seta arising from well-defined tubercule. Antenna with thin seta on basal segment of endopodite. Spine on basal segment of exopodite about 1.5 lengths of middle segment. Spines on apical segments longer than apical segments. IDL of limb I with three setae, seta 1 long; seta 2–3 thin, armed with thin setulae. Single species, Leydigia ciliata Gauthier, 1939 ( Fig. 12 E–F). Length of adult 0.65–1.1 mm . Common species in the region, found in lakes and ponds, rivers and paddy fields. Benthic species, associated with muddy or clay bottom. For detailed description see Kotov et al. (2003) . Known from Africa and tropical Asia (Kotov 2009).