Gliricoptes zapus sp. n. (Acari: Myocoptidae) from Zapus from Washington and British Columbia

Abstract

A new species of myocoptid mite, Gliricoptes zapus, is described from Zapus trinotatus from Washington and British Columbia. The myocoptid mite genus Gliricoptes was previously represented by eight Old World species, six from various genera of dormice (Gliridae), one from a spiny dormouse (Platacanthomyidae), and one from Sicista betulina (Zapodidae) from Poland. The new species described here is the first representative of the genus from North America, and the first myocoptid from a North American zapodid. The occurrence of this genus on two zapodids as well as on the glirids could indicate evolutionary affinities between those groups. This opinion is reinforced by an observation made recently by Fain (1974). In the family Myobiidae the genus Radfordia subgenus Graphiurobia contains four species living on Gliridae, two species on Cricetidae and one species (R. (CG.) ewingi) on an American zapodid. Family Myocoptidae Gunther, 1942 Genus Gliricoptes Lawrence, 1956 Gliricoptes zapus sp. n. (Figs. 1-4) Male (holotype) (Figs. 1-2): Total length (gnathosoma and posterior lobes included) 255 /L, maximum width 156 ,u. Body broadly oval. Posterior lobes broad, longer than wide, posterior margins rounded. Dorsum: Small propodosomal shield present. Hysterosoma bearing a poorly and irregularly sclerotized shield. Setae sc e thick, finely attenuated apically. Venter: All epimera free. Two small adanal suckers. Aedeagus rather long and narrow. Base of genital organ forms a transverse sclerite reaching laterally nearly to g m setae. Legs IV normally developed. Female (allotype) (Figs. 3-4): Total length 324 A/, maximum width 168 A/. In allotype and Received for publication 6 May 1974. 2 paratypes cuticle macerated in posterior part of body. In this area the cuticle is detached and extends to some distance behind the body giving an artificial elongate aspect to the body. Moreover, the hairs which are normally inserted not far from the anus have been pulled posteriorly with the cuticle while their insertion bases remain at their normal places. Cuticular striation poorly visible. Dorsal shields as in male but hysterosomal shield shorter with posterior border slightly concave. Epimera as in the male. Legs: femora III and IV with transverse ventral thickening visible only at certain orientations of the leg. Systematic position of this new species In the relatively long and rounded posterior lobes of the male this species resembles G. graphiuri Fain, 1970, G. betulinus Kok et al., 1971, and G. eliomys Kok et al., 1971. It differs from G. graphiuri by the absence of triangular scales on coxae and trochanters IV, by the longer aedeagus, by the narrower shape of the posterior lobes, and by the smaller size of legs III and larger size of the body. It differs from G. betulinus by the much smaller and shorter size of the aedeagus, from G. eliomys by the presence of sh setae, the longer aedeagus, and the different shape of the postgenital sclerite.