Ololaelaps ussuriensis Bregetova & Koroleva, 1964

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 : 475-477

Ololaelaps ussuriensis Bregetova & Koroleva, 1964

Figures 43–51 .

Ololaelaps ussuriensis Bregetova & Koroleva, 1964: 75 .

Ololaelaps ussuriensis . — Bregetova, 1977: 539; Ren & Guo, 2008: 329; Babaeian et al., 2019: 351; Beaulieu et al., 2019: 5. Specimens examined. Lectotype (here designated), female, Pokrovka, Primorsky Krai, Russia, 19 September 1946, Dubinin and Zhmaeva coll. on Apodemus agrarius ; slide number 4896. Paralectotypes, one female (slide number 4899) and one male (slide number 4897), Ussuriysk, Primorsky Krai, Russia, 9 August 1952, Preobrazhenskii coll. on Apodemus agrarius ; one female (slide number 4900), Kraskino, Primorsky Krai, Russia, 6 September 1952, Preobrazhenskii coll. on Microtus michnoi ; two females (slide numbers 4901 & 4902), Russky Island, Primorsky Krai, Russia, 4 October 1955, Shapiro coll. in nest of Microtus fortis .

Remarks. Ololaelaps ussuriensis was described from the Far East of Russia ( Bregetova & Koroleva, 1964) where it was found on small rodents or in their nests, and has also been recorded in China ( Ren & Guo, 2008) and Iran from soil-litter ( Nemati et al., 2018). Bregetova & Koroleva (1964) designated syntypes for O. ussuriensis ; in this study, a lectotype is chosen among the examined syntypes. The lectotype is necessary to stabilise the distinction betwee O. ussuriensis and the other species discussed here. Babaeian et al. (2019) drew attention to the similarity between O. ussuriensis and O. caucasicus , and stated that Bregetova & Koroleva (1964) distinguished these two species from each other by small, weak or vague differences (e.g. mainly the reticulation of the epipleura, the ornamentation of genitiventrianal shield, and the number of hypostomal denticles). Babaeian et al. believed such small morphological differences may represent intraspecific variations. In the meantime, Ma (2016) also considered that Ololaelaps ussuriensis is a junior synonym of O. sinensis Berlese, 1923 . However, Ma (2016) did not provide any explanation for this decision, nor did he provide the details of the examined specimens. The species was originally described as O. venetus var. sinensis from China ( Berlese, 1923), and Ryke (1962) raised it to the species level and provided some more information. However, they both lack most important details and the type series of this species may never have been re-examined. We also have not had the opportunity to examine the type specimens of O. sinensis in order to confirm this synonymy, but at least we had the opportunity to examine the type specimens of O. ussuriensis and O. caucasicus in order to compare these two species carefully. Therefore, in this study, we retain these three species as distinct species and confirm all diagnostic character states listed by Beaulieu et al. (2019) for each, and herein provide additional clarification of characters for O. ussuriensis based on the examination of type series specimens. All these observations were made on all specimens examined, unless specified: (1) dorsal shield essentially smooth, without reticulation (i.e. not reticulate, but completely micropunctate) over whole surface except ventrolateral margins (epipleura) which are relatively well extended ventrally and lineate-reticulate, cells narrow and oriented mostly longitudinally or diagonally (but not compressed as in caucasicus ) (see Figs 43, 45 ), bearing 39 pairs of setae (Jx seta absent); (2) metasternal setae st4 and metasternal poroids obviously inserted on the sternal shield margin ( Fig. 44 ), posterior margin of shield slightly concave ( Figs 43, 44 ); (3) metapodal elements partly fused to hologastric shield and shield ornamented by scale-like cells and bearing five pairs of pre-anal setae (Jv1–3, Zv1–2) in addition to seta st5 (in all examined specimens) ( Fig. 43 ); (4) hypostomal groove with six transverse rows of denticles, each row with 2–3 relatively large denticles, groove wider anteriorly, progressively narrowing from anterior to posterior ( Fig. 46 ); (5) the pretarsal paradactyli on legs II–IV relatively short, with tips barely extending beyond claws ( Fig. 47 ); (6) insemination structures not discernible; (7) spermatodactyl short, with a straight duct and without hump subapically ( Fig. 48 ); (8) in the male tarsus II bearing a stout spur-like ventral seta (pv2) ( Fig. 49 ), genu II and femur IV with cuticular tubercles (see Figs 50 & 51 ). Supplementary measurements (n=2): (1) lengths of dorsal setae decreasing from anterior to posterior, most of podonotal setae 40–50 and opisthonotal setae 23–30; (2) sternal shield length 115–118, maximum width 189–195, between coxae II 104–107; (3) hologastric shield 400–415 long (4) sternal setae (st1–st4) 55–59, metasternal setae st5 and pre-anal setae (JV1–3, ZV1–2) 44–54; (5) legs: I (530–540), II (435–450), III (387–397) & IV (492–508). See Remarks for O. caucasicus for the main distinctions between the two species.

Figures

FIGURES 43–47. DIC micrographs of Ololaelaps ussuriensis Bregetova & Koroleva, 1964 (lectotype), female. 43, idiosoma in ventral view, showing ornamentation of the hologastric shield; 44, sternal shield; 45, details of peritrematal shield, metapodal elements partly fused to hologastric shield, showing ornamentation of epipleuron (ventrolateral portion of dorsal shield); 46, subcapitulum; 47, tarsus IV, pretarsal paradactyli (p.p).

FIGURES 48–51. DIC micrographs of Ololaelaps ussuriensis Bregetova & Koroleva, 1964 (paralectotype), male. 48, chelicera; 49, tarsus II; 50, genu II, 51, femur IV.