Unionicola Haldeman, 1842

Tuzovskij, Petr V. & Semenchenko, Ksenia A., 2015, Water mites of the genus Unionicola Haldeman, 1842 (Acari, Hydrachnidia, Unionicolidae) in Russia, Zootaxa 3919 (3), pp. 401-456 : 403

Genus Unionicola Haldeman, 1842

Diagnosis (refined after Cook 1974). Adults. Idiosoma typically soft but secondary sclerotization present in a few species; number of idiosomal setae typical for the family Unionicolidae , usually three pairs of setae (Fp, Oi, Pi) not associated with glandularia ( Figs 1A–B ), but in U. ypsilophora only three pairs of setae (Le, Pe, Hv) associated with glandularia; sutures lines between third and fourth coxae usually incomplete obliterated medially; posterior apodemes of anterior coxal groups relatively short; sclerites, bearing setae and glandularia Le, usually larger than sclerites bearing other idiosomal setae; sclerites, bearing seta and glandularium Pe, usually fused with posteromedial margins of fourth coxal plates; basal segments of chelicerae fused medially; pedipalp well sclerotized, P-1 without setae, P-4 usually with three ventral tubercles; gonopore of male terminal or subterminal, never opening in the middle of the dorsum; genital field of females terminal, often with four acetabular plates which bear three pairs of setae medially, occasionally only a single pair of acetabular plates present in female; genital acetabula varying from five pairs to many; excretory pore placed dorsocaudally; I-Leg-2–5 usually armed with large sword setae and without swimming setae; legs II–IV variable with large movable and swimming setae; all legs with claws.

21 species of the genus Unionicola are found in Russia (about 8 % from known numbers of species) therefore we consider to inexpedient in this work the division of the genus on subgenera as it complicates identification of species.

Figures

FIGURES 1 A – B. Unionicola crassipes, female: A, dorsal view; B, ventral view. Scale bar = 200 Μm.