Phylogenetic analysis of Chirocephalus (Branchiopoda: Anostraca), with the description of a new species from Algeria

Abstract

Molecular analyses based on the comparison of Chirocephalus species mtDNA cytochrome oxidase I (COI) sequences obtained from Algeria, Morocco and France with other available sequences were performed. The analysis clari ed the status of the genus Chirocephalus Prévost, 1803 in Algeria and its phylogenetic links with other populations. Three lineages occur in Algeria representing three different species: Chirocephalus salinus Daday, 1910, C. sanhadjaensis Boumendjel, Rabet and Amarouayache, 2018 and a new species sampled in Reghaïa (Alger, Algeria) near Algiers. All these species, belonging to the "diaphanus" group, seem to be endemic to Algeria except C. salinus also present in France (Corsica).The new species C. algeriensis sp. nov. is described and its a nities with other species of the genus are presented. This species is until now restricted to Algiers region and shares several characters with C. diaphanus Prévost, 1803. It is separated from all other species by the shape and size of the second antennal appendages of the male and the female. The resting eggs of C. algeriensis sp. nov. are morphologically similar to those of many Chirocephalus but a variation of size of eggs can be used at a speci c level.

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

“…In the genus Branchipus, cryptic species are also distributed on both continents and some of them have a wide, interrupted distribution in Algeria and France or Italy, which is somewhat similar to the situation of T. stagnalis (Lukić et al 2019). On the other hand, if we compare Tanymastix with Chirocephalus of diaphanus group we observe: that the distribution of the genus Chirocephalus is more continuous, that there are many clades and that there is no clade/species in common between continental Europe (France/Spain/Italy) and Algeria (Renier et al 2013;Boumendjel et al 2018Boumendjel et al , 2023. The phylogeographic model of Rogers (2015) would also explain this different distribution between Chirocephalus spp.…”

“…Thus, the "Monopolization Hypothesis" would explain the strong priority effects of the founding population, which, after installation, would hinder the gene ow of newcomers occupying the same niche (Meester et al 2002). In this case, the success of the European Tanymastix would be linked to the absence of indigenous Tanymatix species in the north of Algeria, and therefore, without local competition, they could easily establish themselves, while, in the case of Chirocephalus, the European populations/species are faced with very strong local competition and do not take root (Boumendjel et al 2018(Boumendjel et al , 2023. Furthermore, the presence of a consistent cystbank of the resident species, which are adapted to local conditions, limits the establishment of the immigrant species (Rogers et al 2015).…”

“…A fragment of the mtDNA gene encoding cytochrome oxidase subunit I (mtDNA COI) was ampli ed using the universal primers LCO1490 and HCO2198 described by Folmer (Folmer et al 1994). The PCR reaction was carried out on a Bio-Rad C1000 Touch thermal cycler for a total volume of 20 µl (see Boumendjel et al 2023). Each reaction contained the following composition: 12.44 µl (H 2 O), 2 µl (Taq10x coralLoad buffer), 1 µl DMSO (DiMethyl Sulfoxide), 1 µl BSA (Bovine Albumin Serum), 0.8 µl dNTP (DeoxyNucleotide TriPhosphate), 0.32 µl (HCO2198), 0.32 µl (LCO1490), 0.12 µl of Taq (recombinant DNA polymerase, Quiagen) and 2 µl of DNA.…”