A historic biogeography of the aquatic fauna of the Levant

Diversity, biogeography, evolutionary relationships, and conservation of Eastern Mediterranean freshwater mussels (Bivalvia: Unionidae)

Located at the junction between Europe, Africa, and Asia, with distinct evolutionary origins and varied ecological and geographical settings, together with a marked history of changes in orogeny and configuration of the main river basins, turned the Eastern Mediterranean into a region of high diversity and endemism of freshwater taxa. Freshwater mussels (Bivalvia, Unionidae) from the Western Palearctic have been widely studied in their European range, but little attention has been dedicated to these taxa in the Eastern Mediterranean region and their diversity and phylogeography are still poorly understood. The present study aims to resolve the diversity, biogeography, and evolutionary relationships of the Eastern Mediterranean freshwater mussels. To that end, we performed multiple field surveys, phylogenetic analyses, and a thorough taxonomic revaluation. We reassessed the systematics of all Unionidae species in the region, including newly collected specimens across Turkey, Israel, and Iran, combining COI + 16S + 28S and COI phylogenies with molecular species delineation methods. Phylogeographical patterns were characterized based on published molecular data, newly sequenced specimens, and species distribution data, as well as ancestral range estimations. We reveal that Unionidae species richness in the Eastern Mediterranean is over 70% higher than previously assumed, counting 19 species within two subfamilies, the Unioninae (14) and Gonideinae (5). We propose two new species, Anodonta seddonisp. nov. and Leguminaia anatolicasp. nov. Six additional taxa, Unio delicatusstat. rev., Unio eucirrusstat. rev., Unio huetistat. rev., Unio sesirmensisstat. rev., Unio terminalisstat. rev. removed from the synonymy of Unio tigridis, as well as Unio damascensisstat. rev. removed from the synonymy of Unio crassus, are re-described. The nominal taxa Unio rothi var. komarowi O. Boettger, 1880 and Unio armeniacus Kobelt, 1911 are proposed as new synonyms of Unio bruguierianus, and Anodonta cyrea Drouët, 1881 and Anodonta cilicica Kobelt & Rolle, 1895 as new synonyms of Anodonta anatina. Also, the presence of Unio tumidus in the Maritza River is confirmed. The phylogeographic patterns described here are interpreted concerning major past geological events. Conservation needs and implications are presented, together with populations and species conservation priorities.

Molecular systematics and phylogeography of the genus Alburnus Rafinesque, 1820 (Teleostei, Leuciscidae) in Turkey

In this study, the phylogeny of Alburnus genus distributed in Turkish freshwaters was performed by analyzing mitochondrial cyt b gene (1141 bp) and COI gene (1551 bp) sequences from 1172 samples representing 112 populations of 24 species through their geographical distribution. According to our findings, 20 valid species are distributed in Turkey of which 18 have already been known. While six Alburnus species (A. battalgilae, A. istanbulensis, A. carinatus, A. schischkovi, A. nasreddini ve A. adanensis) have been synonomized, two new species (Alburnus sp.1 and Alburnus sp.2) from Dicle River and Çapraz Stream/Susurluk River have been identified. Extinct species such as A. akili and A. nicaeensis have not been observed in situ. Phylogenetic tree topologies and haplotype network of the 119 cyt b and 80 COI haplotypes detected in Alburnus species have indicated a consensus tree topology containing twenty lineages, each of corresponding to one species, and three Alburnus haplogroups corresponding to the geographical origins: Eastern Anatolia (I), Mediterranean (2) and Western & Northern Anatolia (3). The results indicate that the divergence between those haplogroups may have occurred during the Middle Miocene-Middle Pleistocene periods (from 14.9 to 5.29 million years).

A river runs through it: tree frog genomics supports the Dead Sea Rift as a rare phylogeographical break

Phylogeographical breaks can be viewed as regional hotspots of diversity where the genetic integrity of incipient species is put to the test. We focus on an understudied species transition from the Middle East, namely the Dead Sea Rift in the Levant region, which presumably divided the tree frogs Hyla savignyi and H. felixarabica. Combining multilocus genetic analyses (mitochondrial DNA and RAD-sequencing) with ecological niche modelling, we test whether the rift effectively acts as a biogeographical barrier preventing this pair from admixing and merging. The answer is yes: despite weak signs of introgression, all parapatric populations were assigned to either species without cyto-nuclear discordance. Yet, the projected distributions under present and glacial conditions largely overlapped in the area, meaning their current parapatric ranges do not represent an ecological transition. Instead, we hypothesize that H. savignyi and H. felixarabica are maintained apart by limited opportunities for dispersal across the barren Jordan Valley, combined with advanced reproductive isolation. Therefore, the Dead Sea Rift may represent a rare phylogeographical break, and we encourage international efforts to assess its contribution to the rich biodiversity of the Middle East.

A new species of Bungona in Turkey (Ephemeroptera, Baetidae): an unexpected biogeographic pattern within a pantropical complex of mayflies

By using an integrative approach, we describe a new species of mayfly, Bungona (Chopralla) ponticasp. n., from Turkey. The discovery of a representative of the tropical mayfly genusBungonain the Middle East is rather unexpected. The new species shows all the main morphological characters of the subgenus Chopralla, which has its closest related species occurring in southeastern Asia. Barcoding clearly indicated that the new species represents an independent lineage isolated for a very long time from other members of the complex. The claw is equipped with two rows of three or four flattened denticles. This condition is a unique feature of Bungona (Chopralla) ponticasp. n.among West Palaearctic mayfly species. Within the subgenus Chopralla, the species can be identified by the presence of a simple, not bifid right prostheca (also present only in Bungona (Chopralla) liebenauae (Soldán, Braasch & Muu, 1987)), the shape of the labial palp, and the absence of protuberances on pronotum.

Phylogenetic relationships of freshwater fishes of the genus Capoeta (Actinopterygii, Cyprinidae) in Iran

The Middle East contains a great diversity of Capoeta species, but their taxonomy remains poorly described. We used mitochondrial history to examine diversity of the algae‐scraping cyprinid Capoeta in Iran, applying the species‐delimiting approaches General Mixed Yule‐Coalescent (GMYC) and Poisson Tree Process (PTP) as well as haplotype network analyses. Using the BEAST program, we also examined temporal divergence patterns of Capoeta. The monophyly of the genus and the existence of three previously described main clades (Mesopotamian, Anatolian‐Iranian, and Aralo‐Caspian) were confirmed. However, the phylogeny proposed novel taxonomic findings within Capoeta. Results of GMYC, bPTP, and phylogenetic analyses were similar and suggested that species diversity in Iran is currently underestimated. At least four candidate species, Capoeta sp4, Capoeta sp5, Capoeta sp6, and Capoeta sp7, are awaiting description. Capoeta capoeta comprises a species complex with distinct genetic lineages. The divergence times of the three main Capoeta clades are estimated to have occurred around 15.6–12.4 Mya, consistent with a Mio‐Pleistocene origin of the diversity of Capoeta in Iran. The changes in Caspian Sea levels associated with climate fluctuations and geomorphological events such as the uplift of the Zagros and Alborz Mountains may account for the complex speciation patterns in Capoeta in Iran.

Phylogeny, phylogeography, and evolution in the Mediterranean region: News from a freshwater mussel (Potomida, Unionida)

The Potomida genus (Bivalvia, Unionida) has a Circum-Mediterranean distribution and like other freshwater mussel species, its populations have suffered dramatic declines. Although this genus is currently considered as monotypic, it has a long history of taxonomic revisions and presently many aspects of its systematics and evolutionary history are unclear. We sampled a total of 323 individuals from 39 different sites across the Potomida genus distribution, and sequenced two mitochondrial (16S rDNA and Cytochrome c Oxidase Subunit I) and one nuclear (28S rDNA) genes to clarify its phylogeny and phylogeographic history. Our results show that the genus includes two well-supported clades, one comprising solely the western Mediterranean species Potomida littoralis, and the other including two eastern Mediterranean species, the Greek endemic P. acarnanica and the Anatolian and Middle Eastern P. semirugata. We suggest that Potomida started radiating during the upper Miocene, and that both vicariance and dispersal events shaped the diversification and distribution of the genus along the Mediterranean region. P. littoralis is further divided in two mitochondrial lineages, one restricted to Europe and the other occurring mostly in North Africa. Moreover, some European basins present both lineages in sympatry. The conservation status of the three recognized species should be reevaluated, particularly P. acarnanica, since it is restricted to two Greek river basins presenting a high risk of extinction. Overall, our results clarify some important gaps in knowledge concerning the phylogeny, phylogeography and evolution of the Potomida genus in the Mediterranean region with important taxonomical, ecological and conservational implications.