Conchogneta glabrisensillata, Bayartogtokh, Badamdorj, 2012

Bayartogtokh, Badamdorj, 2012, The soil mite genus Conchogneta (Acari, Oribatida, Autognetidae), with new findings from Mongolia, ZooKeys 178, pp. 27-42 : 29-31

Conchogneta glabrisensillata sp. n. Figs 1-3

Diagnosis.

Medium in size (378-427 μm in length); rostrum with deep incision reaching level of rostral setal insertion; prodorsal costula long, slightly sigmoid, diverging proximally, but converging medially and again very slightly diverging anteriorly; sensillus smooth, with relatively long stalk and slender, lanceolate head; rostral seta barbed, lamellar and interlamellar setae smooth; prodorsal tubercles Ea small, Ep large; interbothridial region with one pair of tubercles; exobothridial region with small granular tubercles; notogastral setae long, thin.

Measurements.

Holotype: body length 384 μm, length of notogaster 256 μm, width of notogaster 201 μm; paratypes (n = 3) body length 378-427 (405) μm; length of notogaster 250-281 (266) μm; width of notogaster 192-213 (204) μm.

Integument. Body color yellowish brown to light brown. Surface of body and leg segments with very thin, nearly smooth cerotegument. Integument microtuberculate on tubercles, prodorsum, lateral part of prodorsum, notogaster and around leg acetabula.

Prodorsum (Figs 1A, C, D, 2A, B, 3A, B). Rostrum with deep U-shaped incision reaching level of rostral setal insertion in dorsal view, but distinctly projecting anteroventrally in lateral view (Figs 1A, D, 2A). Rostral seta (ro) 30-36 μm long, barbed, curved medially, inserted dorsally on distinct tubercle. Prodorsal costula long, slightly sigmoid, diverging proximally, but converging medially and again very slightly diverging anteriorly (Figs 1C, 3A, D). Lamellar seta (le) thin, smooth, 31-38 μm long, straight, inserted at distal end of costula. Interlamellar seta (in) 15-21 μm long, attenuate, smooth; distance between alveoli of in-in greater than that of ro-ro as viewed in dorsal aspect (Fig. 1A, D). Exobothridial seta (ex) inserted on distinct tubercle, 11-13 μm in length, smooth, directed anterolaterally.Sensillus (ss) with relatively long stalk and slender, smooth, lanceolate head; exposed portion of sensillus 70-83 μm in length (Figs 1D, E, 3C, E, F). Bothridium (bo) large, its opening directed posterolaterally, with large protuberance (tubercle Ha) posteriorly (Figs 1A, 2A, B, 3H). Prodorsal enantiophysis E well developed, Ea small, but well observable; Ep large, subtriangul ar in shape (Figs 1C, 2A, 3A). Interbothridial region with one pair of tubercle, nearly semicircular as viewed in dorsal aspect (Figs 1A, 3B).

Notogaster (Figs 1A, 2B). Oval, slightly narrowed anteriorly, about 1.3 times as long as wide. Anterior margin nearly straight, with large humeral protuberance (tubercle Hp; Figs 2B, 3H); posterior margin evenly rounded as viewed in dorsal aspect (Fig. 1A). Notogastral setae medium long (29-38 μm in length), thin, smooth, not reaching level of insertions of next setal row. Lyrifissure im well developed; other lyrifissures and opisthonotal gland opening not evident.

Gnathosoma (Figs 1B, 2C). Subcapitular mentum slightly wider than long, with minute microtubercles. Hypostomal setae h, a and m medium long, thin, smooth (Figs 1B). Chelicera typical for genus as shown in description of next species, slender with few slightly sclerotized blunt teeth; seta cha about 1.4 times as long as chb, both setae smooth; Trägårdh’s organ small, but distinctly developed. Palp typical for genus as shown in figure 2C, palpal setation: 0-2-1-3-10, including solenidion ω of tarsus.

Epimeral region (Fig. 1B). Pedotecta I and II well developed, covered with minute granules. Epimeral region nearly smooth; setal formula 3-1-3-3, all setae medium long, smooth. Discidium well developed, projected laterally of leg acetabulum IV.

Anogenital region (Fig. 1B). Genital aperture slightly widened anteriorly, anal aperture with same width throughout. Genital, aggenital, anal and adanal setae ad3 medium long; two other adanal setae, ad1 and ad2 relatively long, but all ano-genital setae thin, smooth. Adanal lyrifissure not evident.

Legs (Fig. 2D-G). Dorsal surface of claws smooth, tibia I with large dorso-distal tubercle overhanging tarsus I. Formula of leg setation (including famulus) I (1-5-3-4-18), II (1-5-3-4-15), III (2-3-2-3-15); IV (1-2-3-3-12); formula of solenidia: I (1-2-2); II (1-1-2); III (1-1-0); IV (0-1-0). Homology of leg setae and solenidia showed in Table 1.

Material examined.

Holotype (female): Sevsuul valley, Eastern shore of the Lake Hövsgöl, District Khankh, Province Hövsgöl, litter of cool temperate larch forest ( Larix sibiricus Ledebour, 1833), 51°16'N, 100°74'E, elevation 1680 m, 08 July 2007, Col. B. Bayartogtokh; three paratypes (females) same data as holotype. The holotype and one paratype are deposited in the collection of the Department of Zoology, National University of Mongolia, Ulaanbaatar, Mongolia, and two paratypes are in the collection of the Senckenberg Museum of Natural History, Goerlitz, Germany. All type specimens are preserved in alcohol.

Remarks.

Among the eight known species of Conchogneta , only two of them, namely Conchogneta traegardhi (Forsslund, 1947) and Conchogneta vasiliorum Mahunka, 2006 resemble the present new species in the closely situated structure of prodorsal costulae. However, both mentioned species are different from the new speciesin the barbed head of sensilli as opposed to smooth sensilli in Conchogneta glabrisensillata sp. n. Moreover they differ in conspicuously barbed notogastral setae in contrast to smooth setae in the new species, nearly straight and thinner prodorsal costulae rather than sigmoid, but thicker costulae in the new species, and different structure of prodorsal tubercles Ea and Ep.

The other species, such as Conchogneta dalecarlica (Forsslund, 1947), Conchogneta inundata (Winkler, 1957), Conchogneta iranica Akrami, 2008, Conchogneta willmanni (Dyrdowska, 1929), Conchogneta willmanni herzegowiensis (Willmann, 1941) and Conchogneta weigmanni Mahunka, 2007 are easily distinguishable from the new species by the widely spaced prodorsal costulae, and different structure of prodorsal enantiophyses E.

Etymology.

The specific epithet “glabrisensillata” refers to the smooth sensillus or bothridial seta in the new species.