Holostaspis collina ( Huhta & Karg, 2010 )

Babaeian, Esmaeil, Mašán, Peter & Halliday, Bruce, 2019, Review of the genus Holostaspis Kolenati, 1858 (Acari: Laelapidae), Zootaxa 4590 (3), pp. 301-341 : 309-312

Holostaspis collina ( Huhta & Karg, 2010)

( Figs 10–18 )

Hypoaspis (Holostaspis) montana .— Karg, 1971: 171, 172, Fig. 192 (in part). Misidentification.

Hypoaspis (Pneumolaelaps) montana .— Karg, 1979: 88, 98, Figs 13e and 13f (in part); Karg, 1993: 146, 158, Figs 113e and 113f (in part). Misidentification.

Hypoaspis (Pneumolaelaps) collina Huhta & Karg, 2010: 332 .

Holostaspis collina .— Huhta, 2016: 145.

Specimens examined. Four females—N Slovakia, Malá Fatra Mountains, Martin Town, Martinské Hole Hills, south slope of Krížava Mt. (49°05'37" N, 18°49'26" E), meadow, edge of spruce forest (with Picea abies ), in anthill of Lasius niger (Linnaeus, 1758) ( Hymenoptera , Formicidae ), altitude 1,380 m, April 14, 1991 (3 ♀♀), June 23, 1993 (1 ♀), coll. P. Mašán. Holotype female (No. 7218:3383)—C Finland, Oulu Town, Hailuoto Island, compost of garbage and garden residues, October 14, 2004 (deposited at the Finnish Museum of Natural History—LUOMUS, University of Helsinki, Finland).

Diagnosis (female). Dorsal shield inversely ovoid, with anteriorly lineate-reticulate and posteriorly reticulate, with almost polygonal cells, smooth medially, bearing 39 pairs of setae and 1–4 unpaired accessory setae between J1–J5; most of dorsal setae moderately long, smooth and similar in length; setae Z5 and S5 longest, almost twice as long as the shortest dorsal setae with medial position (Z5 = S5 = 2 x J5); setae J5 with tips reaching beyond posterior margin of dorsal shield. Sternal shield subquadrate, with obscure posteromedial margin (in available specimens) and mostly smooth. Anal shield subtriangular, with well-rounded corners, having anterior margin almost straight and anterolateral angles widely rounded; postanal seta slightly thicker and longer than adanals. Peritremes long, with anterior ends reaching beyond bases of s1. Epistome subtriangular, with central cusp apically rounded or pointed. Fixed digit of chelicera with one subterminal denticle, movable digit edentate. Corniculi with a small notch laterally.

Description. Female (n=4)

Dorsal idiosoma ( Fig. 10 ). Dorsal shield oval, 470–515 µm long and 320–380 µm wide, smooth medially, with uneven lineate-reticulate ornamentation on anteromarginal surface, weak polygonal meshes on posterior region; bearing 39 pairs of setae: 22 pairs (j1–j6, z1–z6, s1–s6, r2–r5) in podonotal area and 17 pairs (J1–J5, Z1–Z5, Px2–Px3, S1–S5) in opisthonotal area and 1–4 unpaired accessory setae between J1–J5; with at least 19 pairs of discernible pore-like structures (four pairs of gland pores and 15 pairs of lyrifissures). All dorsal shield setae simple, smooth, medium in length and subequal (except slightly longer Z5 and S3–S5); setae Z5 (54–61 µm) and S5 (52–58 µm) longest and approximately twice as long as J5 (29–36 µm). Lengths of some other dorsal shield setae: j 1 29–32 µm, z 1 12–17 µm, J4 37–41 µm, S4 45–55 µm.

Ventral idiosoma ( Fig. 11 ). Tritosternum with short base (20–25 µm) and pilose laciniae (57–62 µm). Sternal shield subquadrate, 100–110 µm in length and width, widest at level of coxae II–III (149–156 µm), with anterior margin convex and posterior margin slightly concave (posterior margin obscure in available specimens); whole surface mostly smooth, with a few short, irregular lines anteriorly and laterally; setae short, with tips not reaching bases of following ones (st1 32–35 µm, st2 and st3 35–37 µm); lyrifissures iv1 and iv2 slit-like. Metasternal setae (st4 37–40 µm) and associated lyrifissures iv3 on soft integument; endopodal platelets III–IV subtriangular, narrow and free from sternal shield. Epigynal shield tongue-shaped, elongate, 220–242 µm long and 114–119 µm wide (99–104 µm at level of st5); anterior hyaline margin curved, extending to level between setae st2 and st3; posterior portion with lineate ornamentation pattern forming usually eight elongate cells; genital setae (st5 37–40 µm) inserted on mediolateral margins and associated lyrifissures iv5 on soft integument; adgenital sclerite minute, irregularly shaped, near Zv1 seta. Metapodal platelets suboval. Anal shield 77–82 µm long and 71–74 µm wide, subtriangular, with weak curved sculptural lines anteriorly; postanal seta 37–40 µm long, slightly thickened and longer than adanal setae (27–32 µm); cribrum with narrow band of spicules. Lateral and opisthogastric soft integument with 17 pairs of setae. Poststigmatic section of peritrematal shield narrow, tapered posteriorly and not reaching posterior margin of coxa IV.

Gnathosoma ( Figs 12–14 ). Epistome ( Fig. 12 ) subtriangular, with central apex rounded or pointed. Corniculi relatively narrow, with slim and pointed apex; internal malae projecting medially, with smooth margins, densely fimbriate laterobasally; labrum blade-like ( Fig. 13 ). Deutosternal furrow with six transverse rows of denticles, of which posterior two or three rows narrower, each with 5–12 denticles, and anterior ones wider, each with 15–25 denticles. Lengths of hypostomal and palpcoxal setae: h 1 20–22 µm, h 2 10–12 µm, h3 37–42 µm, pc 20–25 µm. Palp setation 2-5-6-14 -15, as in Fig. 13 . Shape and dentition of chelicera as in Fig. 14 ; lengths of chelicera: the second segment 92–94 µm, fixed digit 20–25 µm, movable digit 22–27 µm.

Legs ( Figs 15–18 ). Tarsi I–IV each with a pair of claws and pulvillus. Lengths of legs: leg I 433–450 µm, leg II 304–310 µm, leg III 272–285 µm, leg IV 376–408 µm. Setae pd on trochanter I, ad1, pd1, pd2, pd3 on femur I, ad1, pd2 on femur II, pd on trochanter III, and ad1 and ad2 on femur IV thickened.

MALE. Unknown.

Remarks. Holostaspis collina was originally only briefly described in Hypoaspis (Pneumolaelaps) by Huhta & Karg (2010), so we here amend their original description. Huhta & Karg’s description is based on a holotype specimen found in compost of garbage and garden residues in Finland, and one paratype specimen was reported as an associate of unidentified ant species of Lasius Fabricius ( Hymenoptera , Formicidae ). In his catalogue of Mesostigmata of Finland, Huhta (2016) transferred H. (P.) collina to Holostaspis .

An examination of the holotype of H. collina by one of us (PM) confirmed the conspecificity of H. collina with the specimens collected in Slovakia. Given that Huhta & Karg (2010) were unaware of H. submontana ( Bai, Gu & Chen, 1994, in Bai, Chen & Gu, 1994), and that the characteristics of the holotype of H. collina are within the range of variability found in H. submontana , we suspect H. collina may be a synonym of H. submontana . In addition, Karg (1971, 1979, 1993) has previously illustrated and misinterpreted H. collina as a variant of Holostaspis montana with longer setae.

Figures

FIGURES 10–14. Holostaspis collina, female. 10. Dorsal idiosoma; 11. Ventral idiosoma; 12. Epistome, variant forms; 13. Ventral gnathosoma with palp; 14. Chelicera.

FIGURES 15–18. Holostaspis collina, female. 15. Leg I; 16. Leg II; 17. Leg III; 18. Leg IV.