Pseudosida szalayi

2. Pseudosida szalayi (Daday, 1898) Localities and specimens found: 46 − 2♀; 49 − 1♀; 50 − 7♀, 3j; 59 − 1♀; 60 − 1♀. Distribution and ecology. According to modern concepts, this species is chiefly distributed in the tropics and subtropics of the Eastern Hemisphere. The northern limit of its range passes through Northern India, Central China and the Russian Far East (the Lower Amur River basin), whereas in the south it reaches New Guinea and north of Australia (Korovchinsky 2010, 2018; Korovchinsky et al. 2021b). Pseudosida szalayi is well known in most Oriental and neighbouring countries under its original name (Korovchinsky 2010, 2013; Chatterjee et al. 2013; Kotov et al. 2013b; Padhye & Dumont 2015; Sinev & Yusoff 2015, 2018; Sinev et al. 2015; Xiang et al. 2015; Lopez et al. 2017; Sharma & Sharma 2017; Siboualipha et al. 2020; Tiang-nga et al. 2020; Choedchim & Maiphae 2023). In addition, in many sources (e.g., Shirota 1966; Fernando 1974; Idris & Fernando 1981; Idris 1983; Sharma & Michael 1987; Michael & Sharma 1988; Sanoamuang 1998; Maiphae et al. 2005, 2008; Tanaka & Ohtaka 2010; Rane 2011, etc.), it has been mistakenly reported in the region as a related Neotropical species P. bidentata Herrick, 1884 (see comments in Korovchinsky 2010, 2018; Chatterjee et al. 2013; Kotov et al. 2012, 2013b; Xiang et al. 2015; Lopez et al. 2017; Sharma & Sharma 2017). In Vietnam, this crustacean has been recorded (including as P. bidentata) only in southern provinces so far (Shirota 1966; Dang & Pham 1979; Sinev & Korovchinsky 2013; present study). The lifestyle and ecology of P. szalayi are poorly studied. It lives mainly among aquatic vegetation, to which the crustacean apparently attaches itself by means of hook-shaped setae on its antennae (Korovchinsky et al. 2021b). Pseudosida szalayi can also be found on the bottom. The species has been recorded in various water bodies and biotopes: littoral zones of lakes, ponds, ditches, channels, paddy fields, swamps, small pools, etc. (Idris 1983; Korovchinsky 2010; Sinev & Korovchinsky 2013; Sinev & Yusoff 2015, 2018; Siboualipha et al. 2020; Choedchim & Maiphae 2023). In our material, a few individuals of P. szalayi were registered only in shallow, vegetation-rich floodplain lakes, both on the bottom and among the roots of a water hyacinth (see Appendix 1).