Fain 1957b: 473, 1964b: 43; Hyland & Clark 1959: 365; Fain et al. 1967: 79, 1972: 71; Smith et al. 1985: 481; Zabludovskaya 1989: 64, 1990: 32.

Type species: Yunkeracarus muris Fain, 1957, by original designation.

Diagnosis. ADULTS. Posterior margin of subcapitulum ventrally with pair of widely rounded lobes. Sternum not fused with apodemes II; apodemes II free, distinctly developed; apodemes III–IV free, very short. Propodosoma without transverse sclerotized bands ventrally. Posterior apodemes of coxal fields II and median transverse sclerite absent. Coxal fields I bearing membranous posterior projections. Small folds posterior to coxal fields II present. Coxal fields III–IV slightly sclerotized. Anus situated ventrally. Tarsi subequal in length to respective tibiae and bearing distinctly developed pretarsi. Trochanters III–IV with distinct ventral folds. Spurs or projections absent on other leg segments. Idiosomal setation (see Table 1): alveoli h1 and h3 present only in Y. hylomyscus; setae si, se, cp, c3, 1a, 3a, h2 all filiform, h2 whip-like; 4a, 4b, g, ps3 all microspines with distinct bases; c2 and f2 alveoli. Leg setation (see Tables 2 and 3): setae pR I–II absent only in Y. limnomys; setae d I–IV, gT I–II, k TIII–IV, mG I–II, vF I–II all filiform, setae d I–IV whip-like; r I–II alveoli; e I–IV, f III–IV, w I–IV, ba I–II, la I–II, r III–IV all indistinct microspines, setae ba I–II situated on nipple-like protrusion; f I–II and s I–IV spur-like; cG I–II and pRI–II microspines with distinct bases or cG I filiform.

FEMALE. Bursa copulatrix opening dorsal or terminal.

MALE. Postgenital shield distinctly developed.

JUVENILE STAGES. Females ovoviviparous. Setal appearances in ontogeny typical for family; no setal delays or disappearances recorded. Larva bearing idiosomal setae si, se, c2, cp, c3, 1a, 3a, h2 (alveoli h1 present in Y. hylomyscus), and leg setae d I–III, e I–III, f I–III, s I–III, ba I–II, la I–II, r I–III, w I–III, gT I–II, k TIII, cG I–II, mG I–II, vF I–II, solenidia ω 1 I–II, ϕI–III, and famulus ε. Gnathosoma with postero-ventral lobes. Apodemes I free. Trochanters III without ventral folds. In protonymph setae g, f2, and ps3 added on idiosoma, and setae d IV, w IV, and r IV on legs. Apodemes I fused to each other by distal ends. Trochanters III–IV with ventral folds. In tritonymph setae 4a and 4b added on idiosoma, and kT IV, e IV, f IV, s IV, ϕIV on legs.

Species included: Y. alticola, Y. apodemi, Y. apomys, Y. ascanicus, Y. faini, Y. hylomyscus, Y. limnomys, Y. lophuromys, Y. microti, Y. muris, Y. otomys, Y. rattus.

Host range and distribution. Probably cosmopolitan although not yet recorded in Australia, with species parasitizing the nasal passages of rodents (Rodentia) belonging to the closely related families Muridae and Cricetidae (see Tables 6 and 7).