Neocrassicheles sternomus, Mašán & Halliday, 2010

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 : 65-68

Neocrassicheles sternomus sp. nov.

( Figs 58, 109–130)

Description. Female ( Figs 58, 109–113). Idiosoma. Dorsal surface not clearly visible in available specimen. Idiosoma 560 µm long and 545 µm wide. Vertical setae j1 short and 18–21 µm long, the longest dorsal setae 46–56 µm in length. Sternal setae st1 and st2 15–21 µm long, st3 27–30 µm long.

Male ( Figs 116, 117, 122, 123, 125, 129 and 130). Dorsal shield 365–425 µm long and 230–265 µm wide. Vertical setae j1 very short, 9–12 µm long, most dorsal setae between 16–25 µm long. Sterno-genital shield 144–163 µm long, anal shield wider than long, 63–69 µm in long, 70–85 µm wide.

Deutonymph ( Figs 114, 115, 118–121, 124 and 126–128). Idiosoma. As for male, domed, suboval, with lateromarginal parts expanded ventrally, well sclerotised ( Figs 118, 119).

Dorsal idiosoma ( Fig. 118). Dorsal shield 400–450 µm long and 240–280 µm wide, entire, covering whole dorsum, suboval, smooth and with weak longitudinal ornamentation ventromarginally, fused to anterior sections of peritrematal shields anterolaterally, widely expanded ventrally, bearing 30 pairs of setae of which at least eleven pairs with ventral position ( Fig. 119). Dorsal setae including vertical setae j1 simple, short and thin, needle-like. Pore-like structures small. Lengths of dorsal setae with similar values as in male.

Ventral idiosoma ( Fig. 119). Presternal platelets absent. Sterno-genital shield oblong, 153–174 µm long, anterior margin slightly undulating, posterior margin acuminate, surface reticulate anteriorly and marginally, with four pairs of sternal setae and three pairs of small slit-like pores ( Fig. 124); sternal setae st5 situated on soft integument close to posterior tip of sterno-genital shield. Endopodal platelets II–III and III–IV elongated, fused, narrowly separated from lateral margins of sternal shield. Post-sternogenital sclerites absent. Anal shield free, 58–69 µm long and 63–74 µm wide, subtriangular, smooth, with three circum-anal setae and large anus ( Fig. 126); post-anal seta slightly shorter than adanals. Exopodal platelets I–III absent, exopodals IV present, narrow and curved. Exopodals, metapodals, peritrematal shields and peritremes as in male adult; post-stigmatic pore outside the shield. Sexual dimorphism of ventral chaetotaxy well developed. Female deutonymph with nine pairs of setae on lateral and opisthogastric soft integument ( Fig. 119), male deutonymph with seven pairs ( Fig. 114), excluding setae st 5 in soft integument between coxae IV. All ventral setae simple, short and needle-like.

Gnathosoma . Epistome as in Figs 120 and 121. Chelicera as in Figs 127 and 128.

Etymology. The species name sternomus refers to the swollen protuberant form of the sternal shield in the female (- oma, tumor).

Material examined. Holotype female, Podunajská Rovina Flatland, 18 May 2009, Bratislava, Podunajské Biskupice [7869]. Paratypes, 3 ♂♂, 5 DN, 26 May 1993, Bratislava, Podunajské Biskupice [7869]; Považský Inovec Mts. , 1 DN, 3 May 2009, Modrová [7373]; Trnavská Pahorkatina Wold , 3 ♂♂, 4 DN, 2 May 1993, Brunovce ( Copromyza ) [7373] ; 5 ♂♂, 17 DN, 2 May 1993, Horná Streda [7373] .

Remarks. Neocrassicheles sternomus is a coprophilous species characteristic of fresh and humid dunghills, strongly decaying plant remains, and sphaerocerid flies such as Copromyza equina and Copromyza nigrina . It has usually been collected together with Crassicheles striatus .