Epicriopsis Berlese, 1916

Masan, Peter, 2017, A revision of the family Ameroseiidae (Acari, Mesostigmata), with some data on Slovak fauna, ZooKeys 704, pp. 1-228 : 1

Genus Epicriopsis Berlese, 1916

Epicriopsis Berlese, 1916a: 34. Type species: Gamasus horridus Kramer, 1876, by original designation.

Epicriopsis . - Evans 1963a: 229; Karg 1971a: 223; Bregetova 1977: 167; Karg 1993: 220.

Diagnosis (adults).

Dorsal shield heavily sclerotised and ornamented, with a pattern of conspicuous tubercles; these tubercles star-like, polygonal, sometimes reduced in size (in Epicriopsis walteri ) or modified into small spines arranged into a rows (in Epicriopsis atuberculatus ). Some dorsal shield setae (6-9 pairs) conspicuous, thickened, extremely long, pilose, and much longer than some of the shortest setae; dorsal shield with 22-28 pairs of setae. In female, sternal setae on sternal shield (st1, st2), soft integument (st3, st4), and epigynal shield (st5); setae st3 rarely on small and rounded pseudo-metasternal platelets (in E. atuberculatus ). Female with anal shield, male with ventrianal shield bearing 3-4 pairs of opisthogastric setae (JV1 on or off the shield). Opisthogastric soft integument with 5-6 pairs of setae in female (JV1-JV3, JV5, ZV2; JV4 present or absent), and five pairs of setae in male (JV4 always absent). Corniculi unsclerotised, undivided, stout, with distal extension and obtuse apex; the apex sometimes with denticles. Fixed digit of chelicera with 3-5 teeth on proximal masticatory area (normally with three teeth, but with 4-5 teeth in species with sharply pointed epistome); at least one of cheliceral digits (fixed digit) with membranous structures. Palptarsal apotele usually three-tined. Genu III, and tibiae III-IV with two anterolateral and one posterolateral setae. Tarsi I-IV each with empodium and claws.

Remarks.

The genus Epicriopsis was previously known from 14 named species ( Epicriopsis atuberculatus , Epicriopsis baloghi , Epicriopsis berlesei , Epicriopsis horridus , Epicriopsis hungaricus , Epicriopsis jilinensis , Epicriopsis langei , Epicriopsis linzhiensis , Epicriopsis mirabilis , Epicriopsis palustris , Epicriopsis rivus , Epicriopsis stellata , Epicriopsis suedus and Epicriopsis walteri ), occurring mostly in leaf litter, soil detritus, raw humus, fungi and moss, in humid habitats in Europe ( Karg 1971a, 1971b, 1993; Kandil 1978), Asia ( Ishikawa 1972, Iavorschi 1995, Ma 2002, Hajizadeh et al. 2013b, Ma and Lin 2016), North America ( Farrier and Hennessey 1993), South America ( Marticorena and Berrío 2014, Narita and Moraes 2016) and Australia ( Halliday 1997). The genus often comprises strongly hygrophilous species found in swamp areas, inundation zones, river beds and floodplain forests.

In the checklist below, ten species of this genus are recognised as valid. Among them, now I recognise five species occurring in Europe ( Epicriopsis horridus = Epicriopsis berlesei , Epicriopsis hungaricus , Epicriopsis mirabilis = Epicriopsis rivus syn. n., Epicriopsis palustris = Epicriopsis baloghi syn. n. and Epicriopsis langei syn. n., and Epicriopsis suedus ), with the new synonymies proposed after my examination of the type specimens and specimens collected in Slovakia. For specific remarks to the individual Epicriopsis species and their synonyms see the checklist below.

The dorsal chaetotaxy of individual species occurring in Europe is not adequately described up to now. The two species ( Epicriopsis rivus and Epicriopsis suedus ) described by Karg (1971a) are known only on the base of illustrations and very short description as a part of an identification key. The dorsal shield bears an uncomplete set of setae in the illustrations of Epicriopsis horridus , Epicriopsis rivus and Epicriopsis suedus by Karg (1971a). Therefore, I carefully checked the number of dorsal shield setae in available Epicriopsis species. Epicriopsis hungaricus , Epicriopsis palustris and Epicriopsis mirabilis (= E. rivus ) possess 24 pairs of setae (j1-j6, J2, J4, z2, z4, z5, Z1, Z3, Z5, s1, s2, s4-s6, S3-S5), E. horridus 23 pairs of setae (j6 absent in comparison with previous three species), and E. suedus 28 pairs of setae (s6 absent in comparison with normal complement of dorsal setae found in most of Ameroseiidae ).

Key to species of Epicriopsis occurring in Europe (adults)

Partial keys to species of Epicriopsis may be found in Karg (1971a, 1971b, 1993), Bregetova (1977), and Kandil (1978). The most complete key is that of Narita and Moraes (2016), based on adult females of the world species (not including Epicriopsis mirabilis ). A new key to the genus is needed to introduce new differential characters and include only valid species and those exclusively reported from Europe. I found that the setation of several leg segments is unstable and relatively highly variable in studied species from Europe, namely Epicriopsis horridus , Epicriopsis hungaricus , E. mirabilis , Epicriopsis palustris and Epicriopsis suedus . All these mentioned species can be reliably separated only with the help of leg chaetotaxy (see Table 1 and 2 ).

1	Dorsal shield with 28 pairs of setae (s6 absent); setae j5 relatively short, not conspicuously thickened and lengthened as some other dorsal setae, with tips hardly reaching to bases of J2; genu I with three and genu III with two ventral setae	Epicriopsis suedus Karg, 1971 (Plates 34 , 76C )
-	Dorsal shield with 23-24 pairs of setae (r2, r3, z6, Z2, S2, and sometimes j6 absent); setae j5 conspicuously thickened and lengthened, reaching apparently beyond bases of J2; genu I or genu III with different ventral setation (av2 of genu I or pv1 of genu III absent)	2
2	Area between lengthened j5 and J2 with one pair of setae (z5 present, j6 absent); genu IV with eight setae of which four dorsal (pd3 absent)	Epicriopsis horridus (Kramer, 1876) (Plate 29 )
-	Area between lengthened j5 and J2 with two pairs of setae (z5 and j6 present); genu IV with nine setae of which five dorsal (pd3 present)	3
3	Setae z5 and j6 relatively longer: z5 with tips reaching beyond bases of j6, j6 reaching beyond bases of J2; genu I and tibia I each with 11 setae of which two ventral (av2 absent); genu III with nine setae of which two ventral (pv1 present); epistome pointed; fixed digit of chelicera with four teeth, except terminal hook	Epicriopsis mirabilis Willmann, 1956 (Plates 31 , 32 )
-	Setae z5 and j6 relatively shorter: z5 and j6 with tips never reaching insertions of j6 and J2, respectively; genu I and tibia I each with 12 setae of which three ventral (av2 present); genu III with eight setae of which one ventral (pv1 absent); epistome rounded; fixed digit of chelicera with three teeth, except terminal hook	4
4	Setae j6 more slender, needle-shaped; genu II with 11 setae of which two ventral (pv1 present)	Epicriopsis palustris Karg, 1971 (Plate 33 )
-	Setae j6 shortened and thickened, spine-shaped; genu II with ten setae of which one ventral (pv1 absent)	Epicriopsis hungaricus Kandil, 1978 (Plate 30 )

Figures

Plate 29. Epicriopsis horridus, female, dorsal idiosoma.

Plate 30. Epicriopsis hungaricus, female, dorsal idiosoma.

Plate 31. Epicriopsis mirabilis, female, dorsal idiosoma.

Plate 32. Epicriopsis mirabilis, female. A Dorsal idiosoma with legs B-C Epistome, variant forms D Dorsal shield, anterior part E Dorsal idiosoma F Dorsal shield, medial part.

Plate 33. Epicriopsis palustris, female, dorsal idiosoma.

Plate 34. Epicriopsis suedus, female (holotype, from Sweden), dorsal idiosoma.

Plate 76. Ameroseiidae spp., female. A-E Structures of sperm access system. A Kleemannia delicata, sperm induction pores (solenostomes) associated with inner margin of coxae III B and D Kleemannia plumigera, solenostomes associated with inner margin of coxae III C Epicriopsis suedus, sacculus foemineus and associated tubuli annulati E Sertitympanum nodosum, tubuli annulati F-H Chelicera. F Asperolaelaps rotundus G Ameroseius renatae H Kleemannia delicata.