Ololaelaps altaiensis Joharchi, 2022

Joharchi, Omid, Stanyukovich, Maria K., Asyamova, Olga S., Döker, Ismail & Tolstikov, Andrei V., 2022, Review of some mites of the genus Ololaelaps Berlese (Acari, Laelapidae) in Russia with description of a new species, Zootaxa 5138 (4), pp. 464-480 : 465-471

Ololaelaps altaiensis Joharchi sp. nov.

( Figures 1–25 )

Type material: Holotype, female, Teletskoye Lake , Altai Republic, Russia, 51°21’N 87°45’E, 1 August 2020, A.A. Khaustov, O. Joharchi and V. A. Khaustov coll., from moss on the shore of the Teletskoye Lake (in TSUMZ) . Paratypes, seven females and one male same data as holotype (in TSUMZ) .

Diagnosis (adult female and male). Dorsal shield broad, smooth throughout except for lightly punctate epipleura (and sigillar scars), length/width ratio ~1.25–1.3, bearing 38 pairs of simple and short setae, plus one unpaired seta Jx (in all examined specimens present), z3 absent; epipleura narrow, lightly punctate. Female sternal shield distinctly reticulate-punctate throughout, except smooth or faintly reticulated posteriorly where overlapped by hyaline flap of hologastric shield, bearing setae st1–st3; posterior margin slightly concave, anterior margin more or less straight; seta st4 and poroid iv3 on soft cuticle, tightly positioned between the sternal and endopodal shields; wider than long, ratio of shield length/width ≃ 0.44. Hologastric shield strongly reticulate-punctate, anteriorly comprising polygonal cells, cells elongated in region anterior to anus, bearing seta st5 and three pairs of pre-anal setae (Jv1, Jv2 & Zv1), Jv3 & Zv2 off the shield (in all examined specimens), peritrematal-hologastric-parapodal shields fused by way of the metapodal platelets (as connecting bridge, Beaulieu et al., 2019). Hypostomal groove with 3–5 relatively large denticles per row. Spermathecal ducts well sclerotised and conspicuous; spermatodactyl with a sinuous duct, and a subapical hump, 0.78× as long as movable digit. Tarsus II of male with a ventral spine (pv2).

Description. Female (n=10) ( Figures 1–21 )

Female. Dorsal idiosoma ( Figs 1 , 7 ). Dorsal shield broad and dome-like, 738–750 long and 540–600 wide, suboval, shield smooth throughout except in the epipleuron area, bearing 38 pairs of setae, 21 pairs of podonotal, z3 absent and 16 pairs of opisthonotal setae, including two pairs of Zx setae (Zx2 & Zx3), usually one unpaired seta (Jx) in all examined specimens present; ventrolateral margins (epipleura) narrow, lightly punctate (= granulate), shield with a delineated marginal strip along its edge ( Figs 1 , 7 ). All dorsal setae slender, relatively short (35–45), with j1 (24–27), z1 (20–23) shorter. Dorsal shield with 21 pairs of pore-like structures, including five pairs of gland openings (gd1, gd2, gd4, gd6, gd9) and 16 pairs of poroids, idm5 and gd4 on posterior and lateral shield margin, respectively (discernible ventrally), see Figures 1 , 7 .

Ventral idiosoma ( Figs 2 , 8–11 ). Tritosternum with paired pilose laciniae (86–89), columnar base 32–37 × 20–22 wide; pre-sternal area with well sclerotised plates ornamented with two or three transverse lines, and weakly sclerotised, lineate-punctate anteromesal to platelets ( Figs 2 , 8, 9 ); sternal shield length 102–106, maximum width 225–253, narrowest between coxae II (115–130), strongly reticulate-punctate over whole surface, except posterior area where overlapped by hyaline flap of hologastric shield smooth or faintly reticulated, bearing three pairs of smooth setae (st1 56–67, st2 54–71, st3 56–69), and slit-like poroids iv1–2, setae reaching beyond base of next setae, posterior margin of shield slightly concave, anterior margin more or less straight ( Figs 2 , 9, 10 ). Metasternal setae st4 (56–64) and metasternal poroids (iv3) located on soft cuticle ( Figs 2 , 9, 10 ); metasternal platelets absent. Endopodal plates II/III completely fused to sternal shield, endopodal plates III/IV large, free and curved, partly overlapped by hologastric shield ( Figs 2 , 9 ). Hologastric shield strongly reticulate-punctate, 400–446 long, 353–401 wide, comprising large polygonal cells anteriorly, cells elongated transversally posteriorly, especially in region anterior to anus ( Figs 2 , 9 ); bearing four pairs of slender setae: st5 (54–61), Jv1 (46–48), Jv2 (54–56), Zv1 (68–60); seta Jv3 (40–42) and Zv2 (40–43) off the shield in all examined specimens; shield bearing three pairs of poroids, including paragenital poroids iv5 and two pairs of ivo; post-anal seta (23–25) shorter than para-anal setae (35–38); anal gland pores (gv3) on posterolateral shield margins, at level slightly posterior to para-anals ( Figs 2 , 8, 9 ), cribrum consisting of a terminal tuft with 3–4 irregular rows of spicules, limited to region posterior to post-anal seta. Soft opisthogastric cuticle with seven pairs of setae, r6 (17–20), Zv2–4 (38–45), Jv3–5 (41–49), two poroids (ivo and ivp) ( Figs 2 , 8 ). Exopodal shield surrounding acetabula II–IV fused with sternal shield via endopodal element between coxae I–II which bear gland pore gvb; peritrematal shield fused anteriorly to dorsal shield at mid-level of coxa II, posteriorly fused with exopodal shield fused with well-developed parapodal element ( Figs 2 , 8, 9, 11 ), peritrematalparapodal shield fused by way of the metapodal platelet ( Figs 2 , 8, 9 ), parapodal element bearing gland pore gv2, peritrematal shield with three poroids (id3, id7, ip) and two gland pores (gd3, gdp) ( Figs 2 , 9, 11 ); peritreme short, reaching mid-level of coxae II ( Figs 2 , 11 ).

Gnathosoma ( Figs 4–6 , 12–15 ). Epistome subtriangular, with slightly and irregularly denticulate ( Figs 4 , 12 ). Hypostomal groove with six transverse rows of denticles, each row with 3–5 relatively large denticles, with smooth transverse ridges anteriorly and posteriorly, groove progressively narrowing from anterior to posterior ends. Hypostomal and capitular setae smooth, h3 (51–55)> h1 (42–46)> pc (30–34)> h2 (27–30) ( Figs 3 , 14 ). Corniculi robust and horn-like, extending slightly moderately palp trochanter. Supralabral process with a narrow and undivided apically ( Fig. 5 ). Internal malae with two pairs of long projections, slightly longer than corniculi (median projections heavily fringed in basal third, lateral projections lightly fringed), lateral projections slightly shorter than median ones; labrum acuminate, slightly longer than internal malae ( Fig. 3 ). Chaetotaxy of palps normal ( Fig. 13 ): trochanter 2, femur 5, genu 6, tibia 14, tarsus 15, all setae smooth and needle-like except al1 and al2 on palp genu and al on palp femur slightly thickened and blunt apically, palp tarsal claw three-tined, third (proximal) tine smaller ( Fig. 13 ). Fixed digit of chelicera with an offset subapical tooth (gabelzahn), followed by three mid-sized teeth and setiform pilus dentilis; dorsal cheliceral setae simple, arthrodial membrane with a rounded flap and normal filaments; cheliceral lyrifissures distinct; movable digit with two similarly sized teeth ( Figs 6 , 15 ).

Legs ( Figs 18–21 ). Legs II (479–502) and III (459–485) short, I (636–652) and IV (640–644) longer. Setation of leg segments I–IV: coxae 2-2-2-1; trochanters 6-5-5-5; femora 13-11-6-6, genua 13-11-9-9, tibiae 13-10-8-10. Chaetotaxy normal for free-living Laelapidae : Leg I ( Fig. 18 ): coxa 0-0/1, 0/1-0, trochanter 1-0/1, 1/2-1 (al thickened), femur 2-2/1, 3/3-2 (ad2, pd2, pd3 slightly thickened), genu 2-3/2, 3/1-2, tibia 2-3/2, 3/1-2. Leg II ( Fig. 19 ): coxa 0-0/1, 0/1-0, trochanter 1-0/2, 0/1-1(al thickened), femur 2-3/1, 2/2-1, genu 2-3/1, 2/1-2 (ad3 & pd2 slightly thickened), tibia 2-2/1, 2/1-2. Leg III ( Fig. 20 ): coxa 0-0/1, 0/1-0, trochanter 1-1/1, 0/1-1(ad longer than others on segment), femur 1-2/1, 1/0-1 (ad2, pd & pl thickened), genu 2-2/1, 2/1-1 (pd1 & pd2 thickened), tibia: 2-1/1, 2/1-1. Leg IV ( Fig. 21 ): coxa 0-0/1, 0/0-0, trochanter 1-1/1, 0/1-1 (ad longer than others on segment), femur 1-2/1, 1/0-1, genu 2-2/1, 3/0-1 (av thickened), tibia 2-1/1, 3/1-2. Tarsi II-IV with 18 setae (3– 3/2, 3/2–3 + mv, md); with thickened some ventral and lateral setae, see Figures 19–21 . All pretarsi with well-developed paired claws, rounded pulvilli, paradactyli on pretarsi II–IV elongate, tips projecting well beyond the claws (see Figs 16 & 19–21 ).

Insemination structures ( Fig. 17 ). Sperm access system similar to that seen in the venetus species group (see Beaulieu et al., 2019), tubuli annulati well sclerotised, proximal ends swollen, rounded and sacculus indistinct.

Description. Male (n=1). ( Figs 22–25 ).

Dorsal idiosoma. Dorsal shield 590 long, 458 wide, covering all dorsal idiosoma, oval-shaped, dome-like. Poroidotaxy, adenotaxy, chaetotaxy and ornamentation essentially as in female.

Ventral idiosoma ( Fig. 22 ). Similar to female except the following: holoventral shield 468 long, 119 wide at level of st2, 311 wide at level of Zv1, strongly reticulate-punctate throughout; shield bearing ten pairs of simple and slender setae (st1–5, Jv1–3, Zv1–2) in addition to circum-anal setae. Exopodal, parapodal and metapodal elements merged with holoventral shield; peritrematal shield free.

Gnathosoma . As female, except internal malae with median projections more fimbriate than in female and without the pair of lateral projections, (see Fig. 24 ); deutosternal rows each with 3–7 denticles; fixed digit of chelicera with three teeth, most distal tooth small; movable digit of chelicera with one mid-sized tooth, spermatodactyl with a sinuous duct, and a subapical hump, 0.78 × as long as movable digit, fringed hyaline arthrodial process at base of movable digit ( Fig. 23 ).

Legs. Chaetotaxy and setae thickness as in female except tarsus II bearing a short, spur-like ventral seta (pv2) (see Fig. 25 ).

Etymology. The specific name is derived from the name of the region (Altai Mountains) in which the type locality occurs.

Differential diagnosis. According to Bregetova & Koroleva (1964), Evans & Till (1966) and Beaulieu et al. (2019), Ololaelaps altaiensis belongs to the venetus species group, due to the fused peritrematal-hologastric-parapodal shields by way of the metapodal platelet (as connecting bridge, see Beaulieu et al., 2019), spermathecal ducts (= tubuli annulati, see Evans, 1992) well-sclerotised and conspicuous, spermatodactyl with a sinuous duct and a subapical hump, dorsal shield with narrow, smooth epipleura (i.e. not reticulate, but micropunctate), setae Jv3 & Zv2 off the hologastric shield (variable character state among this species group). These character states are shared with O. venetus Berlese, 1903 , O. placidus Banks, 1895 and O. sellnicki Bregetova & Koroleva, 1964 but O. altaiensis can be easily distinguished from those three species by the following diagnostic character states: (1) peritremes short, reaching to mid-level of coxae II (vs. peritremes long, usually reaching anteriorly level of coxa I (sometimes slightly less) in O. venetus , O. placidus and O. sellnicki ); (2) dorsal shield with 38 pairs of setae, z3 absent (vs. dorsal shield with 39 pairs of setae in O. venetus , O. placidus and 37 pairs of setae (both z1 and z3 absent) in O. sellnicki ); (3) sternal seta st4 and poroid iv3 inserted on soft cuticle (vs. st4 on sternal shield in O. O. venetus , O. placidus and O. sellnicki ); (4) hypostomal groove bearing 3–5 relatively large denticles in each row (vs. hypostomal denticles are small in O. venetus , O. placidus and O. sellnicki ). Ololaelaps platensis Berlese sensu Ryke (1962) is similar to O. altaiensis in having short peritremes (although more or less reaching coxae I), but in O. platensis , the hologastric shield is free of the parapodal and peritrematal plates. Additional potential distinction for O. altaiensis is the pretarsal paradactyli on legs II–IV are elongated, with their tips projecting well beyond the claws.

Figures

FIGURES 1–6. Ololaelaps altaiensis Joharchi sp. nov., female. 1, dorsal idiosoma; 2, ventral idiosoma; 3, subcapitulum; 4, epistome; 5, supralabral process in lateral view; 6, chelicera in antiaxial view.

FIGURES 7–17. DIC micrographs of Ololaelaps altaiensis Joharchi sp. nov., female. 7, general dorsal view; 8, general ventral view; 9, idiosoma in ventral view; 10, sternal shield; 11, details of peritrematal shield; 12, epistome; 13, palp, with a focus on apotele, enlarged section not to scale; 14, subcapitulum; 15, chelicera; 16, tarsus IV, pretarsal paradactyli (p.p); 17, spermathecal structures.

FIGURES 18–21. Ololaelaps altaiensis Joharchi sp. nov., female. 18, leg I (trochanter to tibia); 19, leg II (trochanter to tarsus); 20, leg III; 21, leg IV.

FIGURES 22–25. Ololaelaps altaiensis Joharchi sp. nov., male. 22, ventral idiosoma; 23, chelicera; 24, DIC micrograph of subcapitulum; 25, DIC micrograph of tarsus II.