Cultroribula vtorovi Krivolutsly, 1971

Bayartogtokh, Badamdorj, 2007, Oribatid mites of the family Astegistidae (Acari: Oribatida) in Mongolia, Zootaxa 1472, pp. 55-68 : 64-66

Cultroribula vtorovi Krivolutsly, 1971

( Fig. 5 )

Cultroribula vtorovi Krivolutsly, 1971 , p. 940, fig. 2.

Cultroribula vtorovi: Krivolutsly, 1975 , p. 184, fig. 378. Furcoppia (Mexicoppia) vtorovi: Subias, 2004 , p. 92.

Diagnosis. Relatively small species; body yellowish in color, covered with thin cerotegument; rostrum with nine teeth, among them three central teeth much larger than lateral teeth; lamellae wide, fused medially; lamellar cusps long and wide, with well-developed lateral and median teeth; rostral and lamellar setae moderately long, with conspicuous barbs; interlamellar setae short, smooth; sensilli short, with club-shaped head; tutoria relatively short and narrow, distally pointed; ten pairs of short notogastral setae; five pairs of genital setae.

Measurements. Body length: 306–318 (313) Μm; width of notogaster 192–202 (198) Μm. In total 4 specimens were measured.

Integument. Integument nearly smooth and shiny in reflected light at low magnification, but at high magnification prodorsum, lateral part of podosoma and peripheral regions of ventral plate exhibit minute granulation. Body yellowish in color.

Prodorsum. Rostrum with nine teeth, among them three central teeth much larger than lateral teeth; among the central teeth median tooth is distinctly larger than two lateral teeth; size of lateral teeth of rostrum nearly same and all of them minute. Rostral setae moderately long, with strong barbs. Lamellae wide, fused medially; lamellar cusps nearly as long as basal part of lamellae, but narrower than the latter, with well-developed lateral and median teeth; lateral teeth of cusps larger than median ones. Lamellar setae about twice as long as rostral setae, conspicuously barbed; interlamellar setae short, smooth. Bothridia large, directed anterolaterad, partly concealed under anterior margin of notogaster. Exobothridial setae short, thin, smooth. Sensilli short, with club-shaped head, with a few barbs at the tip. One of the studied specimens shows a variation of fusiform sensilli ( Fig. 5 C). Tutoria relatively short and narrow, almost reaching the insertions of rostral setae, distal tip pointed ( Fig. 5 A & D).

Notogaster. Oval, longer than wide, dorsosejugal suture broadly rounded; humeral projections poorly developed. Ten pairs of short, thin, smooth notogastral setae subequal in length. Lyrifissures im, ih, ips, ip and opisthosomal gland opening well developed; lyrifissure ia not evident ( Fig. 5 A).

Gnathosoma . Infracapitular mentum nearly as long as wide, without noticeable microtubercles. Hypostomal setae a, m and h medium long, thin, smooth ( Fig. 5 B). Chelicerae narrow, elongate, with a few small teeth. Palp normal for family, palpal setation: 0-2-1-3-8 including solenidion ω.

Epimeral region. Apodemes apo.2, apo. sj, apo.3 and apo.4 well developed, nearly transversely oriented. Epimeral setae medium long, smooth; setal formula: 3-1-3-2, setae 4c indistinct. Discidium well developed, projected distally; circumpedal carina well developed ( Fig. 5 B).

Ano-genital region. Anal and genital apertures situated far from each other, anal aperture about 1.5 times larger than other aperture. Genital aperture sub-quadrangular; genital plates with five pairs of medium long, thin, smooth setae. Aggenital setae thin, smooth, as long as genital setae. Anal aperture widened posteriorly, conspicuously longer than wide; anal and adanal setae equal in size. Adanal lyrifissure well developed ( Fig. 5 B).

Legs. Tarsi heterotridactylous, median claw conspicuously thicker than lateral claws. Femora of all legs with large porose areas. Setae a ’ and a” of legs I and IV strong, with thick barbs. Setation of legs as in Cultroribula taigagica sp. nov.

Material examined. Four specimens (two females and two males): Mt. Altai Tavan Bogd, District Tsengel, Province Bayan-Ulgii, soils of high mountain alpine zone, 48o50’N, 88o50’E, elevation 3860m. a.s.l., 24 July 2004, Col. B. Bayartogtokh.

Ecology. This is a high mountain species and occurs in the soils of high mountain steppe of East Tan-Shan Mountains and Siberia. In Mongolia, it inhabits the wet soils of the high mountains in alpine zone.

Distribution. The range of this species is restricted by the Eastern Palaearctic region, and it is sporadically distributed in some areas of Asia ( Kyrgyzstan, Russia: Siberia and Mongolia).

Remarks. The features of Mongolian materials correspond well with those of the European materials as described or redescribed by Krivolutsky (1971, 1975).

Figures

FIGURE 5. Cultroribula vtorovi Krivolutsky, 1971. A: Dorsal view; B: Ventral view; C: Sensillus and bothridium; D: Prodorsum and anterior part of notogaster.