Leberis diaphanus (King, 1853)

Sinev, Artem Y. & Semenyuk, Irina I., 2021, Males and ephippial females of Oriental Chydoridae (Cladocera: Anomopoda) from Cat Tien National Park, South Vietnam, Zootaxa 4941 (3), pp. 381-398 : 389-391

Leberis diaphanus (King, 1853)

Common species in Cat Tien ( Sinev & Korovchinsky 2013). Species was present in all samples from locality 7, and in most samples from locality 1. Several adult males and ephippial females were found in locality 7 on 15.02.2018; ephippial females were also found in locality 1 on 5.12.2017.

Parthenogenetic females of the species were studied by Sinev et al. (2005) and Neretina & Sinev (2016). Second species of the genus, Leberis punctatus (Daday, 1898) , was found in South-East Asia recently ( Neretina & Sinev 2016), but all studied females in our material have IDL setae morphology typical for L. diaphanus ( Fig. 6B ). Morphology of studied parthenogenetic females fully agrees with the previous descriptions. Males of this species were never reported from nature in South-East Asia, but were obtained by Sinev & Sanoamuang (2011) in culture by hormonal induction. Single ephippial female was found in a population from Borneo ( Sinev & Yusoff 2018). Ephippial females were studied using SEM for the first time.

Ephippial female. Body ( Fig. 5 D–E, 6A–B) high oval, similar in shape to that of parthenogenetic female. Ephippium subtriangular, moderately high, with distinctive dorsal keel and weakly defined egg locules, with sculpture in shape of irregularly spaced depressions with small dots inside them. In preserved specimens ephippium color is yellow-brown.

Male. Morphology of males from studied population ( Fig. 5 F–G, 6C–F) agrees with that of hormonally induced males ( Sinev & Sanoamuang 2011: Fig. 3 ), but basal spine of postabdomen ( Fig. 5G , 6D ) is slightly shorter, and terminal aesthetascs of antennule ( Fig. 6E ) are somewhat longer. These differences are within normal variability of males in Aloninae .

Figures

FIGURE 3. Celsinotum macronyx (Daday, 1898) from locality 1. Ephippial female: A, lateral view; B, dorso-lateral view. Euryalona orientalis (Daday, 1898) from locality 4. Ephippial female: C, lateral view; D, ephippium. Karualona karua (King, 1853) from locality 4. Ephippial female: E, lateral view; F, dorsal view.

FIGURE 5. Karualona karua (King, 1853) from locality 4. Adult male: A, lateral view; B, postabdomen; C, postabdominal claw. Leberis diaphanus (King, 1853) from locality 7. Ephippial female: D, lateral view; E, dorsal view. Adult male: F, lateral view; G, postabdomen.

FIGURE 6. Leberis diaphanus (King, 1853) from locality 7. Ephippial female:A, lateral view; B, IDL of thoracic limb I. Adult male: C, lateral view; D, postabdomen; E, antennule; F, copulatory hook and IDL of thoracic limb I. Leydigia cf. ciliata Gauthier, 1939 from locality 7. Adult male: G, lateral view; H, postabdomen; I, postabdominal claw and distal process of postabdomen.