Liebstadia mongolica, Bayartogtokh, 2001

Bayartogtokh, B., 2001, Oribatid mites of Liebstadia (Acari: Oribatida: Scheloribatidae) from Mongolia, with notes on taxonomy of the genus, Journal of Natural History 35 (8), pp. 1239-1260 : 1245-1248

Liebstadia mongolica sp. nov.

(®gures 10±16)

Diagnosis. Medium in size, very robust species with typical characters of Liebstadia . Lamellae rather long and wide, sublamella and prolamella well developed; all prodorsal setae rather long, distinctly barbed; sensillus with a densely

IGS 10±12. Liebstadia mongolica sp. nov. (10) Dorsal aspect. (11) Ventral aspect. (12) Lateral aspect.

1246 IGS 13±16. Liebstadia mongolica sp. nov. (13) Prodorsum. (14) Anterolateral part of notogaster showing the pteromorpha (right, dorsal view). (15) Leg I, trochanter removed (right, antiaxial aspect). (16) Trochanter, femur and genu of leg IV (right, paraxial aspect).

barbed club-shaped head and a smooth, narrow stalk. Notogaster a little narrower anteriorly than posteriorly; four pairs of areae porosae, oval; pteromorphae small, but rather long, well expanded laterally.

Measurements. Body length 414±460 (441.6) m m; width of hysterosom a 257±312 279) m m; width of proterosoma 152±184 (164) m m; length of lamellae 52±75 70.7) m m; length of sensilli 28±46 (33.3) m m.

Integument. Yellowish brown in colour. Cerotegument very thin, being represented by very small granules. Lateral region of podosoma with rather large, densely arranged granules. Integument nearly smooth.

Prodorsum. Rostrum protruding, but smoothly rounded anteriorly. Rostral setae rather long, conspicuously barbed. Lamellae relatively wide, but distinctly narrowed toward the distal end, and slightly curved inward in dorsal view. Sublamellae well developed, joined to the ventral part of the bothridia. Prolamellae also well developed, reaching to the insertions of the rostral setae (®gures 10, 13). Lamellar setae long, thin, weakly barbed bilaterally, and extending well beyond the tip of the rostrum. Interlamellar setae rather long, nearly as long as rostral ones. Insertions interlamellar setae situated at some distance from median margin of lamellae, and connected with the latter by rather long sublamellae. Sensillus with a clubshaped head, densely barbed, and a smooth, short stalk. Bothridium directed anterolaterad, mostly concealed under anterior margin of the notogaster; posterolateral scale of bothridium well developed (®gures 10, 12, 13).

Notogaster. Oval in shape, slightly longer than wide, a little narrower anteriorly than posteriorly; the widest part is at the level of lyri®ssure im. Surface of notogaster nearly smooth, but numerous muscle sigillae scattered along the lateral and posterior margins. Dorsosejugal suture extending slightly beyond the level of the bothridium and broadly absent medially. Pteromorphae small, but rather long, well expanded laterally (®gure 14). Ten pairs of notogastral setae, fairly long, smooth. Four pairs areae porosae with sclerotized borders. Area porosa Aa situated lateral to seta

; A anteromedial to seta h; A and A situated anterolaterad to setae h and h,

1 3 2 3 2 1 respectively. Lyri®ssures ia, im, ih, ip, ips well developed; ia situated anteromedial seta c; im anterior to area porosa A, ip lateral to seta h; ih and ips visible only

2 1

lateral view, situated very close to each other. Lateroabdominal gland opening gla situated posterolateral to im (®gures 10, 12).

Lateral aspect. Very robust species in lateral view, dorso-ventral thickness in postgenital transect 221±239 (230) m m. Exobothridial region and lateral part of podosoma densely granulated. A number of muscle sigillae located between lamella and pedotecta I and II, and between each apodemata. In lateral aspect, lamella relatively narrow, sublamella well developed, and prolamella reaching to the insertions of the rostral setae. Carina circumpedalis relatively short, not reaching to the lateral margin of the ventral plate. Lyri®ssures ih and ips situated relatively close to each other (®gure 12).

Gnathosoma . Subcapitulum and palps normal for the genus. Chelicerae also normally developed, with sclerotized teeth. Hypostomal surface smooth, hypostoma l setae h and maxillar setae m short and thin.

Epimeral region. Surface of epimeral region with a number of round muscle sigillae. Apodemata apo.2, apo.sj and apo.3 well developed, rather long. Epimeral setae medium in length, slender; all setae nearly same in length. Setal formula of epimerata: 3-1-3-3. Pedotecta I and II relatively small, blunt at tip, outer margin rounded. Discidium well developed as a rounded blade, bearing seta 4c. Carina circumpedalis well developed, but not reaching to the lateral margin of ventral plate gures 11, 12).

Ano-genital region. Surface of anal and genital plates smooth. Anal and genital apertures situated far from each other, the former one far larger than the latter. Distance between genital and anal apertures about 2.5 times as long as the length the former one. Four pairs of genital and one pair of aggenital setae medium in length; seta g slightly longer than the other setae. Distance between bases of

1

1248 aggenital setae scarcely shorter than that between setae ad -ad. Two pairs of anal 3 3

and three pairs of adanal setae distinctly longer than the genital and aggenital setae; seta ad in preanal position. Adanal lyri®ssures iad situated adjacent and parallel to 3

each lateral margin of anal aperture (®gures 11, 12).

Legs. All tarsi monodactylous, dorsal surface of claws with slight serration. The leg setation typical of the genus, only leg I and some segments of leg IV are shown gures 15, 16). The formula of leg setation (including famulus): I (1-5-3-4-1 8); II 1-5-2-4-1 5); III (2-3-1-3-1 5); IV (1-2-2-3-1 2); the formula of solenidia: I (1-2-2); (1-1-2); III (1-1-0); IV (0-1-0).

Material examined. Holotype (male) and 14 paratypes (eight females and six males): Mt. Khangai , Bulgan District, Arkhangai Province, litter of larch forest Larix sibiricus ), 47ss10¾N, 100ss40¾E, 24 June 1990, Leg. B. Bayartogtokh . Holotype and ten paratypes are deposited in the collection of the Department of Zoology, National University of Mongolia. Two paratypes will be deposited in the Natural History Museum , London , and two paratypes in the National Science Museum , Tokyo .

Remarks. The new species is somewhat similar to L. khugniensis sp. nov. However, L. mongolica sp. nov. is distinguishable from the former species by (1) the very robust body in dorso-ventral thickness; (2) diOEerent shape of the notogaster the notogaster of L. mongolica is conspicuously narrowed toward the anterior direction, while the notogaster of L. khugniensis is narrowed posteriorly); (3) the diOEerent situation of notogastral setae la and lm; (4) the lyri®ssures ih and ips situated much closer to each other than in the former species; (5) the pteromorphae relatively longer and wider, and well expanded laterally than in L. khugniensis ; and 6) the smaller body size.

Etymology. The speci®c epithet,`mongolica ’ refers to the region encompassing the type locality of this species.