Description of the first cave dwelling species of the spider genus Trilacuna Tong & Li from Iran (Araneae: Oonopidae)

Four obligate cave fish species have been recorded from Zagros in Iran: Garra typhlops (Bruun and Kaiser, 1944), G. lorestanensis (Mousavi-Sabet and Eagderi, 2016), G. tashanensis (Mousavi-Sabet, Vatandoust, Fatemi and Eagderi, 2016) and Eidinemacheilus smithi (Greenwood, 1976). So far, the only known locality of the latter has been the Loven cave. Here, we extend the known range of the Zagros blind loach (E. smithi) by reporting a new locality, the Tuveh spring, located 31 km south of Loven. We combine morphological evidence with the calculated K2P genetic divergences of 1.39% between Tuveh and Loven to confirm that these populations are conspecific. Our discovery of the second E. smithi population has implications for the conservation of this rare and vulnerable species.

Cave systems fed with hydrogen sulfide-rich groundwater are unique chemoautotrophy-dependent ecosystems. Although globally widespread and known to harbor unique subterranean metazoan communities, they have mostly been studied in Europe and North America, less so in Asia. Here, we report on a discovery of a new species of amphipod crustacean from sulfidic waters of Tashan-Chah Kabootari aquifer from Zagros Mountains in Iran. The new species corresponds morphologically to the melitid genus Tegano Barnard & Karaman, 1982, and Tegano tashanensis sp. nov. is the first amphipod from the superfamily Hadzioidea found exclusively in sulfidic water. Phylogenies derived from the mitochondrial coi and the nuclear 28S rRNA sequences recover T. tashanensis sp. nov. in a clade that contains representatives of the currently para- or polyphyletic genera Barnardomelita, Brachina, Josephosella, and Tegano indicating the need for a revised melitid genus level systematics. This clade comprises marine, freshwater and subterranean species globally distributed in regions that were connected by the ancient Tethys Sea. As such, these taxa may be suitable biogeographic models for studying past dispersal, vicariance and multiple colonization of inland groundwaters.

We report on a new species of Stenasellus Dollfus, 1897 (Isopoda, Stenasellidae) from groundwater of Iran. Stenasellus stygopersicus Jugovic, Malek-Hosseini & Issartel sp. nov. inhabits the Chah Kabootari Cave that is adjacent to the Tashan Cave, the type locality of the first recorded species of Stenasellidae from Iran, Stenasellus tashanicus Khalaji-Pirbalouty, Fatemi, Malek-Hosseini & Kuntner, 2018. Both caves are fed by sulfidic groundwater and belong to the Tashan-Chah Kabootari species-rich aquifer on the Zagros Mountains. Both species are characterized by a large body size (≥ 20 mm), a female-biased sexual size dimorphism, and a distinct black-pigmented Bellonci’s organ. Stenasellus stygopersicus differs from S. tashanicus by a short and wide protopodite of pleopod I, setae set essentially along the apical margin of pleopod I exopodite, the subequal length and width of the male pleopod II protopodite, and deeply bilobed endopodites of pleopods III–V. Molecular evidence suggests that while Stenasellus stygopersicus is sister to S. tashanicus, the species are genetically distinguishable, with divergence time estimates ranging from 23 to 39.8 Ma.

With only 43 described stygobionts and only two isopod species the obligate groundwater fauna of Iran, a vast country with over 10% of limestone surface, is inadequately known. Here, we report the discovery of Asellus ismailsezarii sp. nov. from Zagros mountains, the first eyeless and depigmented asellid isopod from Iran. The new species is morphologically similar to Asellus monticola Birstein, 1932, but it is eyeless and fully depigmented, has a slightly curved pereopod IV and does not bear any setae on proximal margins of exopodite of pleopods IV and V. Species phylogenetic relationships using original and datamined mitochondrial DNA and nuclear rDNA, and estimation of molecular divergences with other Asellus species, suggest that A. ismailsezarii sp. nov. is sister to a larger clade that also contains the European A. aquaticus species complex. Surface populations of Asellus have colonized groundwater at multiple occasions and localities, both in Europe and Asia, giving rise to species and subspecies that have evolved troglomorphisms, such as depigmentation and loss of eyes. Of the 37 formally described species and subspecies of Asellus, 15 are from groundwater, including A. ismailsezarii sp. nov. We predict that many more obligate groundwater Asellus taxa are yet to be discovered in Asia.