Combining field observations and laboratory experiments to assess the ecological preferences ofTanymastix stagnalis(L., 1758) (Crustacea, Branchiopoda) in Mediterranean temporary ponds

Abstract

Malladas de El Saler is a mosaic of dune slacks scattered along a coastal sand bar in the Mediterranean region. Active populations of the fairy shrimp T. stagnalis are exclusively present in one of these ponds. We combined field observations and laboratory experiments to find the ecological requirements of T. stagnalis that determine this habitat exclusiveness and the possibility of future establishment in nearby ponds. Conductivity revealed as a determinant ecological constraint. In the field, the species was restricted to conductivity levels below 1.28 mS cm−1 and in experimental microcosms, hatchability, survival and reproductive potential were detrimental from 2.9 mS cm−1. The observation of life history characteristics from the experimental individuals confirmed the importance of the unpredictable character of Mediterranean temporary ponds in shaping life history strategies, as they hatched early, matured rapidly and produced a high number of cysts. We discuss the essential steps during colonization that may explain the presence or absence in our ponds, and revealed a harsh future for the species if the current conditions of habitat deterioration persist. We suggest several conservation measures, including a cyst bank storage or/and adult translocations to nearby suitable ponds. These measures will ensure (1) the preservation of genetic diversity and (2) healthy metapopulation dynamics with recolonization rates compensating for local extinctions.

First record of Linderiella jebalae Boix, Sala, Escoriza & Alonso 2016 (Crustacea, Branchiopoda, Anostraca) in the Iberian Peninsula. Dispersal across the Strait of Gibraltar?

“…comm.). The relatively short period (15-20 days) occurring between pond filling and the observation of mature individuals suggests that L. jebalae typically occurs of early stages of the flooding cycle, as reported for Linderiella baetica, Tanymastigites lusitanica and Tanymastix stagnalis (Alonso and García-de-Lomas, 2009;Machado and Sala, 2013;Olmo et al, 2015). During periodic samplings, we observed that L. jebalae was absent two months after pond filling, suggesting a short life span, which is also true for Tanymastix stagnalis (1-2.75 months) (Olmo et al, 2015;Lopes da Cunha et al, 2021) and L. baetica (~2 months; Alonso and García-de-Lomas, 2009).…”

“…Thus, the total number of cysts produced in L. jebalae may be higher than those reported here, and multiple clutches or cyst release events throughout the flood cycle are expected, as occurs in other anostracan species (Atashbar et al, 2012;Gharibi et al, 2016). Cyst production reaches 533-545 cysts/female in Branchipus schaefferi (Beladjal et al, 2007); up to 187 cysts/female in Tanymastix stagnalis (Olmo et al, 2015); 579-1094 cysts/female (for 12-18 ºC) in Branchinecta orientalis (Atashbar et al, 2012); about 150-200 eggs per brood in Streptocephalus torvicornis (Nagorskaya et al, 2004); and 174-114 cysts/female (for 20-25 ºC) in Phallocryptus spinosus (Gharibi et al, 2016). Despite other biotic and abiotic factors involved in species prevalence, fecundity may have conservation implications, suggesting that L. jebalae has a greater dispersal potential than L. baetica.…”

Phylogenetic status of Tanymastix stagnalis (Linnaeus 1758) (Crustacea Branchiopoda) from Algeria, with some ecological notes

“…Algerian T. stagnalis populations live in arable sandy pools located in shady areas, with subhumid/humid climate close to the Mediterranean Coast. This type of habitats, especially ponds of costal sand bar, is very similar to that of Spanish populations (Olmo et al 2015). T. stagnalis has been reported to live in temporary pools on sandy soil (Brtek and Thiéry 1995;Zarattini et al 2017), karst systems (Mura and Zarattini 2000), rock pools (Rabet 1994;2001), pools in forests (Gauthier 1928;Rabet 2001) and also in tree holes (Jocque et al 2013).…”

“…It was recorded from December to April at temperatures between 14°C and 22°C in Réghaia pools (Gauthier 1928). In Spain it develops in spring only (Olmo et al 2015), while in Italy, it was found in spring after melting snow (Mura and Zarattini 2000) and also, in autumn after the rst rains (Zarattini et al 2017). In France, it occurs throughout the year in the rock pool of the Fontainbleau forest (Rabet 2001).…”

Distinctive genetic signatures of two fairy shrimp species with overlapping ranges in Iberian temporary ponds

“…However, these two species differ in their geographic range size: B. cortesi is an Iberian endemic thought to be a Tertiary relict (Alonso & Jaume, 1991) while T. stagnalis has a widespread distribution ranging from Scandinavia, Ireland, and south-western (SW) Russia to southern Europe and northern Africa (Algeria) (Brtek & Thiéry, 1995;Samraoui & Dumont, 2002;Young, 1976). Besides their different geographic ranges, the two species show similar strategies (Brendonck, 1996) and their life-history traits differ little (in terms of life span, time to reach maturity or hatching time) being characterised by differences among populations according to local environmental conditions (Cristo et al, 2002;Gascón et al, 2012;Mura, 1991;Mura & Zarattini, 2000;Olmo et al, 2015).…”