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Despite being recorded in Algeria since the nineteenth century, the genus Rhithrogena has never been the object of a taxonomical study and no identified species is known from this country. Investigations of the relict mountain streams of El Kala, north-eastern Algeria, have led to the discovery of a Rhithrogena population. Morphological and molecular analyses identified the species as the Maghrebian endemic Rhithrogena sartorii, so far known only from neighboring Tunisia. We report on the species’ distribution, status, and life cycle and discuss its potential role as a bioindicator in environmental monitoring.

The click-beetle family Elateridae is an abundant and ecologically important component of the saproxylic fauna, and many species are used as key indicators of old-growth forests, a rare and endangered habitat in Europe. Among Elateridae, the tribe Ampedini includes several species with unclear taxonomic status. Here we examined the species status and the relationships between 26 of the 29 Ampedini species recorded in Switzerland using both mitochondrial (CO1) and nuclear (ITS2) markers, and compared our results with the CO1 data publicly available for Europe. Our tree-based species-delimitation analysis was largely congruent with traditional, morphology-based species, with the ITS2 and the combined (CO1+ITS2) datasets corresponding more precisely to morphology than the CO1 dataset. As expected, species with unclear or debated taxonomic status generally corresponded to closely related DNA-based species pairs. Our results support the taxonomic status of some of these ambiguous species, while others require further investigations, including a more exhaustive sampling and new morphological examinations. The Ampedini species tree provided here, which is the first attempt of a DNA-based Ampedini phylogeny, did not support the genera Brachygonus and Ampedus as monophyletic, but further investigations are necessary to confirm this result.

A new species belonging to the speciose genus Electrogena ZurwerraTomka, 1985 is described based on all stages from material collected in Switzerland, northern Italy and Slovenia. Electrogena brulini Wagner sp. nov. is closely related to E. gridellii (Grandi, 1953). A genetic analysis based on the mitochondrial gene CO1, including 9 specimens from 5 populations, reveals a K2P distance of 22% between both species. Our investigations demonstrate that the description of the nymph of E. gridellii sensu Belfiore (1996) refers in fact to both species. Therefore, E. gridellii is redescribed in all stages. The number of bristles on each mandibular prostheca in the nymphs, the shape of titillators in male genitalia and the shape of the subanal plate in female imagines are the main characters allowing discrimination of these two species. This study also shows that in this case it is possible and helpful to use colour patterns to separate two closely related species. The re-examination of the type material of Electrogena vipavensis ZurwerraTomka, 1986 described from western Slovenia indicates that this species is a junior subjective synonym of E. gridellii.

Up to now, the mayfly fauna of Jordan has been completely unknown. Based on material recently collected at approximately 30 localities, a first contribution is provided. At least seven species of Ephemeroptera belonging to three different families occur in Jordan. With four species, the Baetidae is by far the most common and diversified family. Two new species, Nigrobaetis vuatazi Gattolliat & Sartori n.sp. and Baetis monnerati Gattolliat & Sartori n.sp., are described in both larval and imaginal stages. The association of the ontogenetic stages was based on mitochondrial DNA (COI gene). Nigrobaetis vuatazi is closely related to Nigrobaetis arabiensis Gattolliat & Sartori, 2008, recently described from United Arab Emirates, but differs notably from European species especially Nigrobaetis niger (Linnaeus, 1761) and Nigrobaetis digitatus (Bengtsson, 1912). Baetis monnerati belongs to the buceratus species-group, which is known to be very common in the Levant but less frequent in Central Europe. The...

The biodiversity and endemism of Madagascar are among the most extraordinary and endangered in the world. This includes the island’s freshwater biodiversity, although detailed knowledge of the diversity, endemism, and biogeographic origin of freshwater invertebrates is lacking. The aquatic immature stages of mayflies (Ephemeroptera) are widely used as bio-indicators and form an important component of Malagasy freshwater biodiversity. Many species are thought to be microendemics, restricted to single river basins in forested areas, making them particularly sensitive to habitat reduction and degradation. The Heptageniidae are a globally diverse family of mayflies (>500 species) but remain practically unknown in Madagascar except for two species described in 1996. The standard approach to understanding their diversity, endemism, and origin would require extensive field sampling on several continents and years of taxonomic work followed by phylogenetic analysis. Here we circumvent this using museum collections and freshly collected individuals in a combined approach of DNA taxonomy and phylogeny. The coalescent-based GMYC analysis of DNA barcode data (mitochondrial COI) revealed 14 putative species on Madagascar, 70% of which were microendemics. A phylogenetic analysis that included African and Asian species and data from two mitochondrial and four nuclear loci indicated the Malagasy Heptageniidae are monophyletic and sister to African species. The genus Compsoneuria is shown to be paraphyletic and the genus Notonurus is reinstalled for African and Malagasy species previously placed in Compsoneuria. A molecular clock excluded a Gondwanan vicariance origin and instead favoured a more recent overseas colonization of Madagascar. The observed monophyly and high microendemism highlight their conservation importance and suggest the DNA-based approach can rapidly provide information on the diversity, endemism, and origin of freshwater biodiversity. Our results underline the important role that museum collections can play in molecular studies, especially in critically endangered biodiversity hotspots like Madagascar where entire species or populations may go extinct very quickly.

Background Larvae of the Holarctic mayfly genus Rhithrogena Eaton, 1881 (Ephemeroptera, Heptageniidae) are a diverse and abundant member of stream and river communities and are routinely used as bio-indicators of water quality. Rhithrogena is well diversified in the European Alps, with a number of locally endemic species, and several cryptic species have been recently detected. While several informal species groups are morphologically well defined, a lack of reliable characters for species identification considerably hampers their study. Their relationships, origin, timing of speciation and mechanisms promoting their diversification in the Alps are unknown. Results Here we present a species-level phylogeny of Rhithrogena in Europe using two mitochondrial and three nuclear gene regions. To improve sampling in a genus with many cryptic species, individuals were selected for analysis according to a recent DNA-based taxonomy rather than traditional nomenclature. A coalescent-based species tree and a reconstruction based on a supermatrix approach supported five of the species groups as monophyletic. A molecular clock, mapped on the most resolved phylogeny and calibrated using published mitochondrial evolution rates for insects, suggested an origin of Alpine Rhithrogena in the Oligocene/Miocene boundary. A diversification analysis that included simulation of missing species indicated a constant speciation rate over time, rather than any pronounced periods of rapid speciation. Ancestral state reconstructions provided evidence for downstream diversification in at least two species groups. Conclusions Our species-level analyses of five gene regions provide clearer definitions of species groups within European Rhithrogena. A constant speciation rate over time suggests that the paleoclimatic fluctuations, including the Pleistocene glaciations, did not significantly influence the tempo of diversification of Alpine species. A downstream diversification trend in the hybrida and alpestris species groups supports a previously proposed headwater origin hypothesis for aquatic insects. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0758-1) contains supplementary material, which is available to authorized users.

Aquatic larvae of many Rhithrogena mayflies (Ephemeroptera) inhabit sensitive Alpine environments. A number of species are on the IUCN Red List and many recognized species have restricted distributions and are of conservation interest. Despite their ecological and conservation importance, ambiguous morphological differences among closely related species suggest that the current taxonomy may not accurately reflect the evolutionary diversity of the group. Here we examined the species status of nearly 50% of European Rhithrogena diversity using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent (GMYC) model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible. Using sequences from 533 individuals from 144 sampling localities, we observed significant clustering of the mitochondrial (cox1) marker into 31 GMYC species. Twenty-one of these could be identified based on the presence of topotypes (expertly identified specimens from the species' type locality) or unambiguous morphology. These results strongly suggest the presence of both cryptic diversity and taxonomic oversplitting in Rhithrogena. Significant clustering was not detected with protein-coding nuclear PEPCK, although nine GMYC species were congruent with well supported terminal clusters of nDNA. Lack of greater congruence in the two data sets may be the result of incomplete sorting of ancestral polymorphism. Bayesian phylogenetic analyses of both gene regions recovered four of the six recognized Rhithrogena species groups in our samples as monophyletic. Future development of more nuclear markers would facilitate multi-locus analysis of unresolved, closely related species pairs. The DNA taxonomy developed here lays the groundwork for a future revision of the important but cryptic Rhithrogena genus in Europe.