Simocephalus (Echinocaudus) exspinosus (De Geer, 1778)

Dadykin, Ivan A., Sinev, Artem Y., Gu, Yangliang & Han, Bo-Ping, 2023, Spring and autumn fauna of Cladocera (Crustacea: Branchiopoda) in the center of East Asia plain: Hunan and Hubei Provinces of China, Zootaxa 5380 (1), pp. 1-25 : 11

Simocephalus (Echinocaudus) exspinosus (De Geer, 1778) s. l.

(fig. 5 A–G).

A littoral phytophilous species, is relatively abundant in both spring and autumn in ponds, lakes and more rarely inhabits rice fields. S. exspinosus is a cosmopolitan species ( Orlova-Bienkowskaja, 2001; Korovchinsky et al. 2021) occurring in North and South Eurasia, Africa and Australia. It is a new record for Central China, the species was previously found only in the northern part of the country ( Xiang et al. 2015). For a description, see Orlova-Bienkowskaja (2001). According to this study, in the Palearctic S. expinosus coexists with its sibling-species S. congener (Koch, 1841) which differs only in the morphology of the postabdominal claw, having a pecten of 20-25 smaller spines on the outer side instead of 8–12 in S. expinosus . In our material, we found specimens with intermediate number of spines (15–18), thus we consider these taxa as synonyms.