A guide to Oribatid Identification for the ABMI: - Royal Alberta Museum

Almanac of Alberta Oribatida 2.3 13 January 2013Euphthiracarus cribrarius (Berlese, 1904)Also Known As: Phthiracarus cribrarius Berlese; Oribotritia cribraria (Berlese, 1904);Phthiracarus punctulatus Berlese, 1913.ABMI code/Common name: EUPHCRIDiagnostic characters: bo barbed in distal half; genua I-II: 5(2), 4(1); ag2>ag1Overview: Niedbala (2002) reports this European species from much of North America includingAlberta (Cypress Hills) and describes it as Holarctic but absent from the southern Nearctic.Barcodes:ID Check: Determination by DEW based on Niedbala (2002). In his key (p. 85), he distinguishesit from E. flavus (Ewing, 1908) by aggenital seta ag2 being longer and thicker than ag1;however, in his diagnoses and illustrations there are also other differences, especially in thegenual chaetotaxy (e.g. genu I 5(2) vs 4(2)), surface ornamentation (strongly punctate vscovered with strong concavities), and notogastral seta c2 (in line with c1-2 vs insertedanterior to c1-2). This and the following species may represent a species complex.Similar taxa: Euphthiracarus flavus (Ewing, 1908) (see below).ABMI Site Records: 2007: none. 2008: none. 2009: none. 2010: none. 2011: none.DOC (1/2008): [+other] Distribution: AB [Cypress Hills], BC, MB, NS; [Holarctic]Images:Ecology:Literature: Marshall et al. (1987) ; Mahunka & Mahunka-Papp (1995); Niedbala (2002).*Euphthiracarus cf flavus (Ewing, 1908) (ITIS 735834)Also Known As: Phthiracarus flavus Ewing, 1908;ABMI code/Common name: EUPHFLA / Yellow Box MiteDiagnostic characters: aspis 270-300, notogaster 440-480 yellow-brown, foveae shallow, with4-8 internal punctae in micropunctate background; aspis granulate with 2 pairs of carinae;bo (105-135) slender, stalk +/- smooth (very faint barbs), slightly swollen and stronglyspined distally; in (~110-120, in-le 112) & le (~75, le-ro 35) erect, barbed; ro (~70-80)closely inserted, reclinate, acuminate, lightly barbed distally, ex (~5) minute; notogastralsetae erect, barbed in distal half, +/- blunt; c1 (87-105), c2 (82-87), c3 (65-75); genitoanalshields micropunctate; 6+3 genital setae, ag1~ag2 (ag1 18, barbed; ag2 20[27], smooth orbarbed); an1-2 setae flagellate (both ~100), lightly barbed, almost smooth; ad1-3(70)(55)(42), an3 (38), all barbed; alveolus anteriad ag3; heterotridactyl; genua I-II: 4(2), 3(rarely 4)(1)Overview: Box mites are so called because they can withdraw their legs into their body and closethe front part over the rear, like a box being folded shut. Euphthiracarus cf flavus is themost common euphthiracarid box mite in Alberta. The identification is tentative becausethis endemic North American species is very similar to the Holarctic Euphthiracaruscribrarius and the differences between the two species may not be significant. Niedbala44