Veigaia hubarti, Mašán & Grazyna & Madej, 2011

Mašán, Peter, Grazyna & Madej, 2011, Description of two cave-dwelling mites of the genus Veigaia (Acari: Mesostigmata: Veigaiidae) from Belgium: V. hubarti sp. n. and V. leruthi Willmann, 1935, Journal of Natural History 45 (13 - 14), pp. 751-765 : 754-757

Veigaia hubarti sp. nov.

( Figures 1 , 2 A–D)

Material examined

Holotype

Female – Belgium, Luxembourg Province , Hotton Village, Les Grottes de Hotton Cave, alluvium of an underground brook, soil, 30 October 2002, leg. J.M. Hubart and M. Dethier.

Paratype

Female – the same data as for holotype.

Description (female)

Dorsal idiosoma ( Figure 1A )

Idiosoma 590–630 µm long and 270–310 µm wide. Dorsal shield 525–555 µm long and 275–300 µm wide, with deep lateral incisions reaching almost to setae J1; those incisions terminally with specific irregular curvature. Podonotal region longer than wide (longer than opisthonotal region), subpentagonal, widely rounded anteriorly, rounded on shoulder margins, slightly sinuous posterolaterally, with delicate reticulate pattern on lateral surfaces, bearing 22 pairs of simple, smooth and spine-like setae, including setae r4 situated on the shield. Anterior margin of podonotum connected with peritremes; peritremes with anterior ends reaching the bases of setae z1. Opisthonotal region subtrapezoid, bowl-like, wider than long, widely rounded laterally, convex posteriorly, with slight marginal expansion between setae J4, finely reticulated on lateral surfaces, bearing 12 pairs of simple, smooth and spine-like setae. Most dorsal setae with a well-developed minute basal mamelon and generally subequal in size, but length of dorsal shield setae slightly decreasing posteriorly: podonotal setae, including those in dorsocentral row, slightly longer than setae on opisthonotum (j-series setae except vertical setae 33–50 µm, J-series setae 27–36 µm; j2 48–50 µm, j3 38–42 µm, j4–j6 33–36 µm, J1 32–34 µm, J2 30–32 µm, J3 29–31 µm, J4 27–30 µm); only setae s1, s2 and r4 conspicuously shorter (s1 and r4 12–13 µm, s2 14 –16 µm), z1 and z2 moderately shorter (z1 21–23 µm, z2 24–25 µm), j2 and s3 moderately longer (j2 48–50 µm, s3 44 –48 µm), vertical setae j1 distinctly longer (60–65 µm). Longest opisthonotal setae 32–36 µm long, J5 off the shield and 27–30 µm long. Posterior soft integument with a pair of small suboval sclerites close to posterior margin of idiosoma.

Ventral idiosoma ( Figure 1B )

Presternal platelets not observable. Sternal shield oblong, 180–183 µm in length, weakly sclerotized, anterior and posterior margins not clearly defined, surface smooth except for poorly defined short sculptural lines in lateral areas; anterolateral corners well-developed, wide; lateral sternal constriction between coxae II standard and 99–104 µm in width. Sternal shield with three pairs of subequal sternal setae (st1 37–39 µm, st2 30–34 µm, st3 33–36 µm) and two pairs of lyrifissures. Each metasternal plate seemingly free from endopodal sclerite, bearing seta st4 (31–32 µm) and an associate lyrifissure, subtriangular in shape, not connected with sternal shield. Genital shield subtriangular, constricted at the level of genital setae, weakly sclerotized and hyaline anteriorly, almost smooth on surface, bearing a bilobed structural line at the level between metasternal plates and another transversely oriented medial line between coxae IV, both as a component of endogynium; shield with three pairs of unequal setae (st5 29–32 µm, Jv1 35–38 µm, Zv1 12–13 µm), fused with anterolateral corners of ventral shield in metapodal regions. Ventral shield wider than long, 199–211 µm in width, subrectangular, with rounded corners, bowl-like, posteriorly convex or straight, distinctly reticulate to transversely striate on lateral surfaces, with four pairs of subequal setae (Jv2 and Jv3 34–37 µm, Zv2 24–26 µm, Zv3 36–39 µm); anterolateral corners free from elements of parapodal or peritrematal shielding, in metapodal regions with punctiform organs, each bearing seven pores. Peritrematal shields reduced to very narrow posterior strips, each with a minute post-stigmatic seta on posteriormost surface ( Figure 2D ). Anal shield subtriangular, subequal in width and length (75–83 µm wide and 78–80 µm long), smooth, with a total of five setae (three circum-anal setae and a pair of preanal setae); length of anal shield setae slightly decreasing posteriorly: Jv4 32–33 µm, adanal setae 25–27 µm, postanal seta 20–21 µm. All setae on ventral shields simple, needle-like and mostly smooth. Dorsolateral and ventrolateral membranous integument with 12 pairs of simple, smooth and spine-like setae.

Gnathosomal structures

Epistome ( Figure 2A ) with a thick column-like central process and relatively large and dentate lateral projections; central process smooth laterally, slightly and regularly broadened distally, with a truncate and serrate tip. Corniculi specific, very slightly constricted medially and broadened distally, with almost truncated tips and two small subapical denticles on inner side ( Figure 2B ). Chelicerae normal for genus and 501–518 µm long; distal segment 302–314 µm long, terminal cheliceral digits relatively long and slim (movable digit 171–184 µm).

Spermathecal structures ( Figure 2C )

Coxae IV associated with well-developed and sclerotized tubular structures. Tubes well-observable, evenly sclerotized, thin, relatively long, with several bends and normal rounded tips.

Legs

All legs with a well-developed pretarsus and ambulacral apparatus, including pulvillus and two claws. All leg segments without projections. Legs I and IV longer than idiosoma: legs I 640–650 µm, legs II 490–500 µm, legs III 460–470 µm and legs IV 695–723 µm long. Tibia IV with a long and upright dorso-distal sensory macroseta (85–95 µm). Tarsus I 132–138 µm, tibia I 116–120 µm, tarsus IV 194–202 µm and tibia IV 126–132 µm.

Etymology

This species is named after the recently deceased Belgian speleologist and biospeleologist Jean-Marie Hubart, who was one of the collectors of this new troglophilous species in Belgium.

Notes

In general appearance, Veigaia hubarti sp. nov. is closely related to V. perinsolita , in the arrangement of some of the following idiosomal, gnathosomal and spermathecal structures: (1) vertical setae j1 at least 2.5 times longer than paraverticals z1; (2) punctiform organ each with seven or eight pores; (3) subapical part of hypostomal corniculus modified, with denticles or tubercles on surface; (4) central process of epistome columnar, lateral projection of epistome relatively large; (5) cheliceral digits relatively long and slim; (6) spermathecal tubes well-developed, long and with several bends. The new species may be easily distinguished from this and the other related species by the characters introduced in the identification key and Tables 1 and 2.

Figures

Figure 1. Veigaia hubarti sp. nov., female. (A) Dorsal idiosoma; (B) ventral idiosoma. Scale bar represents 100 µm.

Figure 2. Veigaia hubarti sp. nov. and Veigaia leruthi. (A–D) Veigaia hubarti sp. nov., female. (A) Epistome; (B) corniculus, dorsal view; (C)tubular structures of insemination apparatus associated with coxae IV; (D) posterior section of peritreme with peritrematal shield. (E–H) Veigaia leruthi. (E) Movable digit of chelicera with spermatodactyl, male; (F) tubular structures of insemination apparatus associated with coxae IV, female; (G) epistome, male; (H) corniculus, female, dorsal view. Scale bars represent: F, 100 µm; C–E,G, 50 µm; A, B, H, 25 µm.