Marin I.N. 2021. The shrimps from the bottom: a new species of stygobiotic atyid shrimps of the genus Xiphocaridinella from the world-deepest Verevkina Cave // Arthropoda Selecta. Vol.30. No.4: 521–530 [in English].
A.N. Severtsov Institute of Ecology and Evolution of RAS, Moscow 119071, Russia. E-mail: coralliodecapoda@mail.ru
doi: 10.15298/arthsel.30.4.07
ABSTRACT. A new species of the genus Xiphocaridinella Sadowsky, 1930 (Crustacea: Decapoda: Atyidae), Xiphocaridinella demidovi sp.n., and two specimens of X. dbari Marin, 2019 are described from the bottom section (–2212 m) of the world’s deepest Verevkina Cave, located in the Arabika karst massif of the Gagra Ridge, southwestern Caucasus. Consequently, these species are the most deep living troglobionts/stygobionts in the world, whose taxonomic status is officially confirmed. Based on morphology and DNA analysis, both species are closely related representing sister clade separated for 6% by COI mtDNA gene marker. From the latter species and related congeners, the new species can be easily separated by a relatively long rostrum, pointed distally and reaching the distal margin of basal antennular segment, slender carpus of pereiopod II, the presence of 3 ischial spines and reduced exopods on pereiopods III–IV as well as stouter/wider telson. Due to the discovery of Xiphocaridinella demidovi sp.n., 14 species of the genus Xiphocaridinella are currently known from the Colchis Lowland of the southwestern Caucasus.
KEY WORDS: barcoding, stygobiotic, shrimp, Verevkina Cave, Arabika, Caucasus.