Gammarus liuruiyui sp. nov. (Amphipoda, Gammaridae), a new blind species from Tian Shan, China

Abstract

A new species of the genus Gammarus Fabricius, 1775 is described and illustrated from the Tian Shan, China. Gammarus liuruiyui sp. nov. is characterized by eyes being absent; pereopods V-VII bases not expanded; uropod III with scale-like inner ramus, second article of outer ramus vestigial; and posterior margins of epimeral plates nearly straight. Detailed morphological comparisons with related species are discussed. Genetic distances of the new species and related species are provided as proof of the species delimitation.

Morphology and zoogeography of the burrower-like gammarid Gammarus koshovi (Bazikalova, 1946) (Crustacea, Amphipoda, Gammaridae) – An overlooked and poorly known species in the Siberian fauna

“…Among the Central Asian members of Gammarus (Martynov 1935), the Tuvan-Mongolian G. koshovi, because of its small size, gravitates to a poorly distinguishable species from the springs of Turkestan, but the forms described by Martynov, despite their small size, still possess elongated antennae and not shortened pereopods, and are clearly distinguishable by their reduced eyes (see also Gammarus parvioculatus Sidorov, Hou & Sket, 2018in Sidorov et al 2018. Furthermore, there is no close similarity with species of the highly diversified Altay and Tian-Shan group of Gammarus (Zhao et al 2017;Zheng et al 2020). This indicates that the territory of Siberia / Mongolia, possibly the basin of the middle Yenisey, is inhabited by a small burrower-like form of Gammarus, the origin and phylogenetic relationships of which are unresolved.…”

“…The genus Gammarus J.C. Fabricius, 1775 is a large Holarctic / Sino-Indian epigean / subterranean group of amphipods that is typically found to be morphologically monotonous at high latitudes (Culver et al 1995), with a number of distinctly divergent narrowly localized endemic species at the southern border of the range (Sidorov et al 2018;Zheng et al 2020). However, the historical reasons for this distribution are not entirely known.…”

A new Gammarus species from Xinjiang Uygur Autonomous Region (China) with a key to Xinjiang freshwater gammarids (Crustacea, Amphipoda, Gammaridae)

“…However, only eight Gammarus species are described in Xinjiang. Particularly, seven of them are endemic species, including Gammarus tastiensis Hou, G. decorosus Meng, Hou & Li, G. brevipodus Hou & Li, G. takesensis Hou & Li, G. tianshan Zhao, Meng & Hou, G. simplex Zhao, Meng & Hou, G. liuruiyui Zheng, Hou & Li ( Hou 2002 ; Meng et al 2003 ; Hou et al 2004 ; Zhao et al 2017 ; Zheng et al 2020 ) and one is a widespread species ( G. lacustris Sars, 1863) in alpine lakes. The amphipod diversity of Xinjiang still remains incompletely understood.…”

A new Gammarus species from Xinjiang Uygur Autonomous Region (China) with a key to Xinjiang freshwater gammarids (Crustacea, Amphipoda, Gammaridae)

“…However, only eight Gammarus species are described in Xinjiang. Particularly, seven of them are endemic species, including Gammarus tastiensis Hou, G. decorosus Meng, Hou & Li, G. brevipodus Hou & Li, G. takesensis Hou & Li, G. tianshan Zhao, Meng & Hou, G. simplex Zhao, Meng & Hou, G. liuruiyui Zheng, Hou & Li (Hou 2002;Meng et al 2003;Hou et al 2004;Zhao et al 2017;Zheng et al 2020) and one is a widespread species (G. lacustris Sars, 1863) in alpine lakes. The amphipod diversity of Xinjiang still remains incompletely understood.…”