Ilyocryptidae

Sinev, Artem Y. & Yusoff, Fatimah M., 2015, Cladocera (Crustacea: Branchiopoda) of Sabah state in Borneo Island, Malaysia, Zootaxa 4000 (5), pp. 581-591 : 585

Family Ilyocryptidae

Ilyocryptus spinifer Herrick, 1882 . Uncommon in Sabah, found in one pond, one stream and in a paddy field. Benthic species, associated with muddy or clay bottom. For detailed description see Kotov & Dumont (2000). The species is cosmopolitan, no evidence of non-cosmopolitanism has been found ( Kotov & Dumont 2000), common in the Oriental region.

Ilyocryptus yooni Jeong, Kotov & Lee, 2012 . Single specimen ( Fig. 1 A–D) was found in a small stream (loc. 25), co-occuring with I. spinifer . I. yooni belongs to the agilis -line sensu Kotov & Elías-Gutiérrez (2009), which is characterized by at least a short distance between proximalmost lateral seta and anus, short spinules at the base of ventral margin of the postabdominal claw, and posterior setae of valves with additional spines ( Fig. 1 A–B). It differs from its sibling-species with complete moulting, I. agilis and I. isanensis , by the absence of any spinules between bases of teeth of preanal margin of postabdomen ( Fig. 1 D). I. yooni can be differentiated from I. spinifer by complete moulting and by lateral row of spines on postabdomen ending at anal margin. For detailed description see Jeong et al. (2012). The species is known from Far East of Russia, Japan, Korea and North China ( Jeong et al., 2012), recently it was found on Hainan island ( Sinev et al., 2015 in press).

Figures

FIGURE 1. Cladocera from Sabah State, Borneo Island, Malaysia. A-D, Ilyocryptus yooni Jeong, Kotov & Lee, 2012 from locality 23. A, lateral view. B, setae of posterior margin of valves. С, postabdomen. D, preanal margin of postabdomen. E, Anthalona sp., parthenogenetic female from locality 12. F-J, Coronatella cf. acuticostata (Sars, 1903), parthenogenetic female from locality 13. F, lateral view. G, posteroventral corner of valves. H, postabdomen. I, labrum. J, outer (ODL) and inner (IDL) distal lobes of limb I. K, Chydorus idrisi Sinev, 2014, postephippial female from locality 5.