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

In this study, we conducted a molecular analysis, based on the comparison of mtDNA sequences of cytochrome oxidase I (COI) of the species Tanymastix stagnalis Linnaeus, 1758 from Algeria, with other available sequences. Phylogenetic analysis clarified the status of this species and its phylogenetic links between European and North African populations. This analysis clearly demonstrated that the only two populations from Algeria (Reghaïa and El Frine) are included within European sub-clad comprising northern Spain, France, northern Italy and Germany. We also provided ecological data over a decade of monitoring, which revealed that the population of T. stagnalis from El-Frine is stable and active during winter and spring. It lives in sandy pools and prefers low temperatures and conductivity (11.9 ± 2.2 °C, 0.26 ± 0.15 mS cm⁻¹, respectively). The mean density of its individuals was 1.43 ± 3.44 ind. L⁻¹, with an egg-bank of 0.35 ± 0.14 egg cm⁻³. The cohabitation of T. stagnalis with the Decapoda Atyaephyra desmaresti (Millet, 1831) in the El-Frine ponds is reported for the first time. Conservation measures should be undertaken to protect this endangered species in North Africa.