Mixozercon sellnicki ( Schweizer, 1948 )

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 : 3-4

Mixozercon sellnicki ( Schweizer, 1948)

Parazercon sellnicki Schweizer, 1948: 23 .

Zercon sellnicki .― Sellnick, 1958: 337; Schweizer, 1961: 166; Karg, 1971: 309; Petrova, 1977: 591. Mixozercon sellnicki .― Halašková, 1963: 206; 1969a: 343; Błaszak, 1974: 49; Karg, 1993: 329; Mašán & Fenďa, 2004: 56; Błaszak et al., 2007: 104.

Diagnosis. Central and submarginal setae of podonotum smooth, except j1 and j2 longer and pilose. Setae J1- J2 and Z1 short, smooth, J3-J5 and Z2-Z3 short, pilose, other J-, Z- and S-setae elongate, brush-like, plumose.

Setae R1 pilose, longer than other R-setae, which are smooth and thorn-like. Setae J5 situated between dorsal cavities. No dorsal seta long enough to reach the base of the following seta. Setae S1 situated lateral to Z1. Pores Po2 situated on a line connecting Z2 and S1. Podonotum covered by tile-like pattern; distinct punctation present on whole opisthonotum. Dorsal cavities well-sclerotised, saddle-like, with smooth anterior margin. Adgenital and post-genital sclerites absent.

Distribution. Iceland, Sweden, Switzerland, Germany, Latvia, Poland, Slovakia and Romania.

Remarks. We examined the type material of the species deposited in the Natural History Museum of Basel (syntypes on slides He 159, He 170 and He 176). On the slides labelled as “ Parazercon sellnicki ” there are also other mesostigmatid mite species, which might be confusing. Schweizer (1948) designated five females and two males as syntypes, but we found no male specimens on the slides. In Slovakian specimens found by Halašková (1963), setae j2 are short and smooth, and J2 are pilose, which was insufficient for establishing a new taxon, perhaps as a result of intraspecific variation. In a later diagnosis of Halašková (1969a), J2 is described as smooth. In Halašková’s drawing there is only one pair of setae on the anterior margin of the ventri-anal shield, but Błaszak (1974), Halašková (1969a) and Błaszak (1979) indicated that there are two pairs of setae in that position. The second pair of ventri-anal setae on the anterior margin of ventri-anal shield was probably present but not clearly visible, according to the diagnosis in Halašková (1969a).