Boreozercon, Díaz-Aguilar, Irma & Ujvári, Zsolt, 2010

Díaz-Aguilar, Irma & Ujvári, Zsolt, 2010, New zerconid mites (Acari: Mesostigmata: Zerconidae) from Canada, with a review of the genus Mixozercon Halašková, 1963, Zootaxa 2555, pp. 1-29 : 17

Genus Boreozercon gen. nov.

Diagnosis. Adults. Peritrematal shield bearing two setae, p1 short and smooth, p2 elongate and pilose, extending beyond lateral margin of idiosoma, situated in the middle of the shield, both visible in dorsal view. Peritrematal shield separated from the podonotal shield by a narrow slit of interscutal membranous cuticle; in the female its posterolateral ends are pointed and expanded posteriorly, reaching setae R5, in the male its posterolateral ends fused to the ventri-anal shield. Peritremes short, straight or slightly bent. Adgenital gland openings gv2 not developed in female; in males a pair of adgenital pores present posterolateral to the sternogenital shield, with a very fine sclerotisation, as a small microplatelet. A pair of narrow post-genital sclerites may be present in female. Anterior margin of ventri-anal shield with one pair of setae, total number of ventri-anal setae 15, setae Vl1 absent. The antero-dorsal shield slopes abruptly anterior to the vertical setae. Lateral margin of opisthonotum with eight pairs of plumose R-setae. Dorsal cavities small, conspicuous. Epistome with a bifurcate medial process.

Notes on the genus. The new genus belongs to the group having short and smooth p1, longer p2, posteriorly expanded peritrematal shield and eight pairs of plumose R-setae on the margin of opisthonotum, similarly to Eurozercon Halašková, 1979 , Paleozercon Błaszak, Cokendolpher & Polyak, 1995 , and Xenozercon Błaszak, 1976 b. Boreozercon is unique among Zerconidae by having only 15 ventri-anal setae (Vm1, Vm2, Vm3, Vi2, Vi3, Vl2, Ad and Pa present, Vi1 and Vl1 absent). The new genus differs from both Asian genera Eurozercon and Xenozercon by the presence of conspicuous dorsal cavities, the absence of adgenital pores in females, and the shape, and the position of the J and Z setae. Besides the ventri-anal chaetotaxy, Boreozercon can be distinguished from Paleozercon by the pilosity of setae p2, the arcuate posteromedial margin of peritrematal shield and the absence of gv 2 in female.

Although the female of the genus Amerozercon Halašková, 1969 b is unknown, the male bears several similar characters to that of the newly established genus, for example plumose dorsal and marginal setae, medium-sized pilose p2 and the lateral fusion of peritrematal and ventri-anal shields. The two genera can be distinguished by the shape of the slit between the peritrematal and ventri-anal shields (peritrematal shield presumably truncated and not expanding posteriorly in Amerozercon ) and the number of ventri-anal setae (Vi1 absent, Vl1 and two additional pairs of setae are also present).

Type species. Boreozercon emendi sp. nov.

Etymology. The name of the new genus refers to the boreal climate zone, where the type species has been collected. Gender masculine.