Combined effect of temperature and salinity on hatching characteristics of three fairy shrimp species (Crustacea: Anostraca)

Abstract

The combined effects of temperature and salinity on hatching performance of three anostracan species, Phallocryptus spinosa, Branchinecta orientalis and Streptocephalus torvicornis from East and West Azerbaijan, Iran, were studied. The cysts were kept for 10 days at seven different temperatures (12, 15, 18, 21, 24, 27 and 30°C) and four salinity conditions (0, 5, 10, and 15 gL) and the effects of the resulting 28 experimental conditions on hatching patterns (duration of pre-hatching period, hatching percentage at first day of hatching, cumulative hatching success) were examined. Results were tested by ANOVA and multiple regression was applied to generate contour models by polynomial equation. The hatching performance in all species was significantly affected by temperature and salinity. Based on contour plot analysis, maximum hatching for P. spinosa, B. orientalis and S. torvicornis cysts was registered at temperatures 19-25ºC, 18-23ºC and 16-20ºC, respectively, within the same salinity range of 0-1 gL–1 The highest cumulative hatching success among the species was observed in P. spinosa at the combination of 24°C and 0gL–1(88. 98%). No hatching was observed for eggs of S. torvicornis and B. orientalis incubated at lower (<15ºC) and higher (>27ºC) temperature, respectively. The pre-hatching period was prolonged with increase in salinity and decrease in temperature and was highest in P. spinosa (7.7 days at 12°C and 15 gL salinity). High hatching success was observed over wide ranges of temperature and salinity in P. spinosa eggs which demonstrates one of the possible mechanisms responsible for the wide distribution of this species

Updated checklist and distribution of large branchiopods (Branchiopoda: Anostraca, Notostraca, Spinicaudata) in Tunisia

“…Such a binomen was erroneously adopted by subsequent workers (e.g. Ketmaier et al 2008, Alonso and Ventura 2013, Rogers 2013, Atashbar et al 2014. We herein correct this oversight; since the species is currently ascribed to the masculine genus Phallocryptus, its correct name is Phallocryptus spinosus (Milne-Edwards, 1840).…”

Combined impacts of warming and salinisation on trophic interactions and mortality of a specialist ephemeral wetland predator

“…Rapid salinity regime shifts could, accordingly, have drastic impacts on wetland biota, even inhibiting the viability of resting eggs or dormant life history stages. Indeed, loss of invertebrate diversity under salinisation has been reported in many studies (Atashbar et al., ; Nielsen et al., ; Toruan, ), and the loss of mature zooplankton due to the breaching of salinity thresholds may have profound implications for the reproductive success and persistence of populations under environmental change. Furthermore, in addition to direct lethal effects, salinity increases may have indirect effects that impact wetland biota across different life history stages (Hintz & Relyea, ), and this necessitates further examination, alongside other environmental context‐dependencies.…”

“…Whilst the influence of temperature on biotic interactions is well studied (e.g. Englund, Öhlund, Hein, & Diehl, ), the role of salinity in mediating species interactions is often ignored, despite a close association with temperature regimes (Atashbar, Agh, Van Stappen, Mertens, & Beladjal, ). Salinity is a pervasive factor that affects aquatic biodiversity and species distributions, and in arid regions ionic compounds often accumulate in association with anthropogenic changes to land cover and land use (Jolly, McEwan, & Holland, ; Nielsen, Brock, Petrie, & Crosslé, ; Toruan, ).…”

Reproductive performance of fairy shrimpBranchinecta orientalis(G. O. Sars 1901) (Crustacea: Anostraca), fed with effluent of rainbow troutOncorhynchus mykiss(Walbaum 1792) ponds

“…The fairy shrimp Branchinecta orientalis (G. O. Sars 1901) is a non‐selective filter feeder of plankton and suspended material like other fairy shrimps (Beladjal, Peiren, Dierckens, & Mertens, ), which inhabits vernal pools. These pools periodically dry, particularly during summer, and are very important habitats for large branchiopods (Atashbar, Agh, Van Stappen, Mertens, & Beladjal, ), many of which are endangered (Kneitel, Samiylenko, Rosas‐Saenz, & Nerida, ).…”

“…Especially for fresh and brackish water species, fairy shrimp may be a valuable alternative for the use of the widely used larvae (nauplii) of the brine shrimp Artemia , but relatively little is known about their life cycle, except for a few studies, for example Beladjal, Khattabi, and Mertens (), Beladjal, Peiren, Vandekerckhove, and Mertens (), Dararat, Starkweather, and Sanoamuang (), and Atashbar et al. ().…”