Melicharidae, Hirschmann, 1962

Mašán, Peter, Joharchi, Omid & Abramov, Vladimir V., 2021, A new genus and two new species of melicharid mites (Acari: Mesostigmata) associated with wood-decaying fungi and mycophagous erotylid beetles (Coleoptera: Erotylidae) in Europe, Zootaxa 4980 (1), pp. 157-173 : 160

Identification key to genera of Melicharidae reported from the Palaearctic (females)

1. Laciniae of tritosternum short and thick, fused in basal portion, with long and dense pilosity forming a typical brush-shaped appearance; cheliceral denticles long, narrow, sharp and usually slightly curved, fixed digit with terminal hook forked; anterior rostral setae (h1) thickened, with distal flattening, nearly paddle-shaped..... Mycomelichares Mašán & Joharchi , gen. nov.

− Tritosternum with thin and long laciniae, laciniae sparsely and finely pilose, never brush-like; cheliceral denticles otherwise formed, fixed digit with terminal hook usually simple; setae h1 thin or thick, always tubular along their whole length (not flattened in distal portion)................................................................................. 2

2. Podonotal part of dorsal shield narrower, with at most 16 pairs of setae (lacking all r- setae and at least s2 and s3, sometime s1 and/or s4, these situated on soft integument close to lateral margins of the shield); deutosternal furrow markedly narrowed, five anterior hypognathal rows each usually with one rarely two denticles; metasternal platelets absent; all R- setae on opisthonotal portion outside dorsal shield........................................................ Melichares Hering, 1838

− Podonotal part of dorsal shield wider, with 20‒24 pairs of setae including all setae of j, z, s series and some to all of r2-r6 (at least r2 and usually r3), setae z3 present or absent; deutosternal furrow well developed, wide, five anterior hypognathal rows each usually with more than two denticles, fifth row with several denticles....................................... 3

3. Anus on ventrianal shield bearing six pairs of pre-anal setae and three circum-anal setae; tibia IV with only nine setae (pl2 absent); pilus dentilis of fixed cheliceral digit setiform; posterior ends of peritrematal shields broadly fused with exopodal platelets IV.............................................................. Orthadenella Athias-Henriot, 1973

− Anus on anal shield bearing only three circum-anal setae (and 1–2 pairs of pre-anal setae in Proctolaelaps intermedius Athias-Henriot and Proctolaelaps ventrianalis Karg ); tibia IV with ten setae (pl2 present); pilus dentilis of fixed cheliceral digit formed as membraneous structure; posterior ends of peritrematal shields free or narrowly fused with exopodals IV.............. 4

4. Fixed cheliceral digit with pointed or rounded distal projection (except in Mucroseius insolitus Trach, Khaustov & Lindquist ); leg IV with 1–2 erect macrosetae on telotarsus (pd2, sometimes ad2)...................... Mucroseius Lindquist, 1962

− Fixed cheliceral digit without distal projection (except in Proctolaelaps nipponicus Ishikawa ); leg IV usually without macrosetae (pd2 never a macroseta)....................................................... Proctolaelaps Berlese, 1923