Crassicheles striatus (Berlese)

Mašán, Peter & Halliday, Bruce, 2010, Review of the European genera of Eviphididae (Acari: Mesostigmata) and the species occurring in Slovakia 2585, Zootaxa 2585, pp. 1-122 : 47-51

Crassicheles striatus (Berlese)

( Figs 50–57, 59–64, 171 and 173)

Uroiphis striatus Berlese, 1903: 245 .

Iphidoides concentricus Oudemans, 1904: 140 . New synonymy.

Eviphis concentricus .— Oudemans, 1915: 149; Karg, 1963: 276; Shoemake, 1970: 77.

Crassicheles concentricus .— Karg, 1963: 279; 1971: 125; 1976: 3; 1993: 96; Evans & Till, 1979: 191; Evans, 1980: 37; Samšiňák, 1984: 48; Makarova, 1993: 18; Urhan, 2006: 225.

Thinoseius concentricus .— Hirschmann, 1966a: 12.

Amendments to diagnosis (adults and deutonymph). Female ( Figs 50–53, 55, 56, 59, 60). Idiosoma 557 µm long and 489 µm wide; vertical setae j1 14–17 µm long; the shortest anteromedial dorsal setae 8–12 µm in length, and the longest idiosomal setae 40–45 µm in length; sternal setae 15–20 µm long.

Male ( Figs 54, 61, 62). Dorsal idiosoma ( Fig. 61). Dorsal shield 315–350 µm long and 240–260 µm wide, elliptical, entire, completely covering dorsal surface, longitudinally striated in lateral parts and smooth medially. Seta j1 16–24 µm long, j5 12–15 µm long, J3 13–16 µm long; J5 3–6 µm long, Z5 8–11 µm long. Dorsal shield fused with anterior ends of peritrematal shields anterolaterally at level of anterior margin of coxae II.

Ventral idiosoma ( Fig. 62). Sterno-genital and anal shield separate; sterno-genital shield oblong, anterior margin undulating, tapered and acuminate posteriorly, distinctly reticulate over whole surface, with four pairs of subequal needle-like setae and three pairs of pores. Exopodals IV narrow, curved. Peritrematal shields moderately widened medially, with short post-stigmatic section. Anal shield subtriangular to subcircular, wider than long, 57–67 µm in length and 67–77 µm in width, with relatively large anus and three needle-like circum-anal setae; post-anal seta slightly shorter than adanals. Opisthogastric soft integument with seven pairs of setae.

Deutonymph ( Figs 57, 63, 64, 171, 173). Idiosoma suboval, dorso-ventrally flattened. Sexual dimorphism of dorsal and ventral chaetotaxy well developed. Female deutonymph with slightly longer dorsal setae and more numerous setae on lateral and opisthogastric soft integument than male deutonymph.

Dorsal idiosoma ( Fig. 63). Dorsal shield 315–390 µm long and 230–280 µm wide, entire, covering whole dorsum, bearing 30 pairs of setae, surface coarsely and irregularly ornamented; medial region densely reticulate; lateral parts with longitudinal striation. Dorsal setae relatively long and needle-like, only vertical setae j1 lance-like; z1 minute, inserted ventrally. Seta j1 21–32 µm long; j3 33–38 µm long, j4 36–41 µm long, j5 35– 46 µm long, J3 39–51 µm long, J5 26–35 µm long, and Z5 27–32 µm long.

Ventral idiosoma ( Fig. 64). Presternal platelets absent. Sternal shield relatively large, oblong to subtriangular, well sclerotised, 114–140 µm long, surface reticulate, anterior margin undulating, posterior margin tapered and acuminate, bearing four pairs of setae and three pairs of pores. Endopodal platelets II-III and III- IV separate, free on soft integument, not fused to sternal shield. Sternal setae st5 placed on soft integument close to posterior margin of sternal shield. Post-genital sclerites and metapodal platelets absent. Anal shield subtriangular to subcircular, wider than long, 59–65 µm in length, 66–77 µm in width, weakly striate, with relatively large anus and three subequal needle-like circum-anal setae. Exopodal platelets I–III absent, exopodals IV present, narrow and curved. Peritrematal shields strongly reduced, very narrow; peritremes well developed, thickened and nodulated close to stigma, anterior ends reaching lateral margin of coxa I; post-stigmatic pore distinct, placed on soft integument. Lateral and opisthogastric soft integument with ten pairs of setae in female deutonymphs ( Fig. 57), with seven pairs of setae in male deutonymphs ( Fig. 64, in both excluding st5 setae); all ventral setae simple, short and needle-like.

Gnathosoma . Cheliceral segments and digits relatively stout and robust ( Fig. 171). Epistome as in Fig. 173.

Remarks. There are five slides and 26 specimens (2 ♂♂ and 24 DNs) of this species, labelled Uroiphis striatus , in the Berlese Acaroteca. They are mostly in good condition and clearly visible. Berlese did not designate types for this species, but on the basis of his original description, the specimens from Portici (slides 13/ 19–20 and 21/50) undoubtedly belong to the authentic syntype material of Berlese. There are also a further three slides also labelled Uroiphis striatus (159/12–14) bearing two deutonymphs of Uroiphis scabratus collected from Sardinia in 1915, thus collected after the original description of U. striatus by Berlese in 1903. Examination of these slides showed that U. striatus is clearly conspecific with the Palaearctic species commonly identified as Crassicheles concentricus .

Crassicheles striatus was known only from descriptions of the male and deutonymphal stages ( Berlese 1903; Karg 1963; Samšiňák 1984), to which we now add the description of the female. The male has the normal complement of 30 pairs of dorsal shield setae ( Fig. 61). Our description of the female is based on two specimens, one of which is fragmented. The intact female has 56 dorsal shield setae, which are provisionally identified in Fig. 50. Some of the setae are in unusual positions, possibly caused by the soft unsclerotised nature of the idiosoma. Seta Z3 is missing from the right side of the specimen, represented only by its insertion. Seta Z4 is completely missing from the left side. One of the pairs of S setae is missing from both sides of the specimen, either S4 or S5. Clarification of the true presence or absence of these setae will depend on collection of more females.

This is a common and abundant species with affinity for strongly decayed organic substrates such as dunghills and stable manure, or strongly rotted plant remains. It is most abundant in fresh excrements of large herbivorous animals, and rotting dung with a high water content. Deutonymphs, and sometimes males, are frequently found on various Diptera , especially on coprophilous Sphaeroceridae . The female specimen reported from Bukovské Vrchy Hills (Kalná Roztoka Village, Havešová Forest), labelled Crassicheles concentricus , and mentioned by Fenďa & Mašán (2003), belongs to the species Rafaphis microsternalis .

Occurrence in Slovakia. (a) Verified or reliable published data. Kremnické Vrchy Hills: Turček [7279] ( Samšiňák 1984). Žitavská Pahorkatina Wold: Veľké Janíkovce [7477] ( Sidor 1986).

(b) New data. Borská Nížina Lowland: 2 DN, 23 May 2009, Veľké Leváre [7468]. Malé Karpaty Mts.: 4 DN, 14 May 1993, Bratislava , zoopark [7868]; 1 ♂, 1 DN, 9 May 2009, Bratislava , zoopark [7868]. Muránska Planina Plateau: 2 DN, 28 August 2002, Muráň, Studňa [7286]. Podunajská Rovina Flatland: 8 ♂♂, 11 DN, 26 May 1993, Bratislava, Podunajské Biskupice [7869]; 2 ♀♀, 2 ♂♂, 3 DN, 18 May 2009, Bratislava, Podunajské Biskupice [7869]. Považský Inovec Mts.: 1 DN, 3 May 2009, Modrová [7373]. Trnavská Pahorkatina Wold: 2 DN, 12 April 1992, Lúka [7373]; 17 DN, 25 April 1993, Horná Streda [7373]; 1 DN, 2 May 1993, Brunovce ( Aphodius ) [7373]; 2 DN, 2 May 1993, Brunovce ( Ontholestes ) [7373]; 3 DN, 2 May 1993, Brunovce ( Physiphora ) [7373]; 76 ♂♂, 111 DN, 2 May 1993, Horná Streda [7373]; 1 DN, 5 October 1997, Horná Streda [7373].