Iphidozercon colliculatus, Gwiazdowicz & Marchenko, 2012

Gwiazdowicz, D. J. & Marchenko, I. I., 2012, Two New Species Of Iphidozercon (Acari: Ascidae) With A Key To Females, Acta Zoologica Academiae Scientiarum Hungaricae 58 (1), pp. 41-52 : 46-48

Iphidozercon colliculatus sp. n.

( Figs 5–8 )

Description. Female (N=10). Dorsum ( Fig. 5 ). Dorsal shield oval, length 310–330 µm, width 210–230 µm distinct foveate sculpture throughout. 18 pairs of setae on podonotal part of shield and 14 pairs of setae on opisthonotal part of shield. All setae fine, smooth and pointed, length of 15–20 µm, except j1 (10 µm, inserted ventrally), and two antero-lateral setae s1, s2 (ca 10 µm).

Venter ( Fig. 6 .) Tritosternum with trapezoidal base (30 µm) and finely pilose laciniae (45 µm). Sternal shield rectangular, 55–60 × 35–40 µm, setae st1–st3 smooth and pointed, length 10 µm. Metasternal setae st4 (10 µm) on soft membrane. Genital shield small and narrow (55–60 µm), spatulate posteriorly. Genital setae st5 (15 µm) outside the shield. Anal shield relatively large 55 µm long, 45 µm wide with para-anal setae (12–13 µm) and post-anal seta (15 µm). Narrow cribrum below post-anal seta. Sternal, genital and anal shields are unornamented. Stigmata located at level of coxae IV, peritremes extending anterior to coxae I, projecting for a short distance behind stigmata. Peritremal shields wide. Opisthogastric integument behind coxae IV with two pairs of oval metapodal plates (15 × 10 µm; 10 × 7–8 µm) and several pairs of very small (5–6 × 2–4 µm) platelets. Opisthogastric setae JV1–JV5, ZV1–ZV2 10–15 µm long.

Gnathosoma. Hypostome with robust horn-like corniculi and four pairs of setae. Anterior seta h1 longest (30 µm), internal seta h3 (20 µm), palp coxal seta (25 µm) shorter, external seta h2 (10 µm) shortest. Seven transverse rows of hypostomal denticles present, numbers of denticles per row (anterior to posterior) 10, 14, 12, 12, 17, 12, 9 ( Fig. 7 a ). Chelicera typical of genus, fixed digit with four teeth, movable digit with two teeth ( Fig. 7 b ), other details of chelicerae not visible in available specimens. Epistome with central prong longest, its distal end club-like and denticulate, lateral prongs shorter, with denticulate outer margins ( Fig. 7c ).

Legs and palps. Lengths of legs: I – 220–230 µm, II – 190–200 µm, III – 170–180 µm, IV – 200–210 µm. Setation of genua I–II–III–IV: 12–9–7–7 ( Fig. 8b ) av1 absent from genu II; tibiae 12–9–7–7 ( Fig. 8c ). Tarsus II to IV each with the dorsoproximal setae ad2 and pd2 short and straight ( Fig 8d ). Palp apotele 2-tined ( Fig. 8a ).

Etymology. The name of this species reflects the colliculate ornamentation of the dorsal shield.

Material examined: Holotype: Female. Russia, Khabarovsk Region, environs of Boytsovo village , in litter of Pinus koraiensis – broad-leaved forest (46°58’48’’ N, 134°19’57’’ E, 500 m a.s.l), 15 August 1991, leg. I. I. VOLONIKHINA. Paratypes: 9 females, same data as holotype .

Differential diagnosis. Iphidozercon colliculatus sp. n. is similar to I. australis GWIAZDOWICZ et HALLIDAY, 2008 . Both species have colliculate sculpture on the dorsal shields. In both species the length of the peritreme (including the short section extending beyond the stigma) is similar, as is the shape of the sternal and genital shields. Additionally, 9 setae (av1 absent) are located on genu II in both species. Nevertheless, many differences exist between both species. In I. australis dorsal setae J1–J3 are long and reach the bases of the following setae, while in I. colliculatus these setae are short and do not reach the bases of the following setae. In I. colliculatus the peritremal shield is wide and in I. australis the shield is narrower. In I. australis the epistome has a central elongated prong ending in three denticles, while in I. colliculatus it has many tiny denticles. In I. australis the movable digit has three, while in I. colliculatus it has two teeth.

Figures

Fig.5. Iphidozercon colliculatus sp. n. – dorsal view

Fig.6. Iphidozercon colliculatus sp. n. – ventral view

Fig. 7. Iphidozercon colliculatus sp. n. – hypostome (a), chelicera (b), epistome (c)

Fig. 8. Iphidozercon colliculatus sp. n. – palp tarsus, mac – macroseta, ap – apotele (a), genu II (b), tibia II (c), tarsus II (d)