A new obligate groundwater species of Asellus (Isopoda, Asellidae) from Iran

By

Malek Hosseini, Mohammad Javad
Jugovic, Jure
fatemi, yaser
Kuntner, Matjaz̆, 1971-
Kostanjšek, Rok
Douady, Christophe J.
Malard, Florian

Type

Article

Date of Publication

2022-03-11

Original Publication

Subterranean Biology

Volume

42

Pages

97--124

Subjects

Asia , Crustacea , Groundwater , molecular phylogeny , taxonomy , troglomorphy

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/subtbiol.42.79447

 

Abstract

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.