Liebstadia elongata, Bayartogtokh, B., 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: 1248-1252

publication ID

http://doi.org/ 10.1080/00222930152434490

persistent identifier

http://treatment.plazi.org/id/F95087A5-FFF1-724D-F6B6-FBB998E8674A

treatment provided by

Felipe

scientific name

Liebstadia elongata
status

sp. nov.

Liebstadia elongata   sp. nov.

(®gures 17±23)

Diagnosis. Medium in size, rather long and relatively robust species with typical characters of Liebstadia   . Lamellae rather wide, sublamella and prolamella well developed; all prodorsal setae long, barbed; sensillus with a club-shaped head and smooth, narrow stalk. Notogaster long, narrow; four pairs of areae porosae, oval; pteromorphae very narrow, almost inconspicuous.

Measurements. Body length 476±529 (498.1) m m; width of hysterosom a 248±317 282.1) m m; width of proterosoma 156±193 (173.8) m m; length of lamellae 64±83 75.4) m m; length of sensilli 28±37 (31.3) m m.

Integument. Yellowish brown in colour. Cerotegument very thin, being present very small granules. Lateral region of podosoma with small scattered granules. Integument nearly smooth.

Prodorsum. Rostrum slightly protruding, but smoothly rounded anteriorly. Rostral setae rather long, conspicuously barbed. Lamellae relatively wide, but slightly narrowed toward the anterior end. Sublamellae well developed, joined to the ventral part of bothridia. Prolamellae also well developed, reaching to the insertions of the rostral setae (®gure 20). Lamellar setae long, thin, weakly barbed bilaterally, and extending well beyond the tip of the rostrum. Interlamellar setae rather long, slightly longer than rostral ones. Insertions of interlamellar setae situated relatively close to IGS 17±19. Liebstadia elongata   sp. nov. (17) Dorsal aspect. (18) Ventral aspect. (19) Lateral aspect.

the median margin of the lamellae, and connected with the latter by sublamellae. Sensillus with a club-shaped head, densely barbed, and a smooth, short stalk. Bothridium directed anterolaterad, mostly concealed under anterior margin of notogaster; posterolateral scale of bothridium well developed (®gures 17, 20).

Notogaster. Shape is elongate oval, about 1.7 times as long as wide. Surface of notogaster nearly smooth, but numerous muscle sigillae scattered along the lateral margins. Dorsosejugal suture extending well beyond the level of the bothridium and broadly absent medially. Pteromorphae very narrow, slightly expanded laterad, sometimes inconspicuous (®gure 21). Ten pairs of notogastral setae, medium in 1250 IGS 20±23. Liebstadia elongata   sp. nov. (20) Prodorsum. (21) Anterolateral part of notogaster showing the pteromorpha (right, dorsal view). (22) Leg I, trochanter removed (right, antiaxial aspect). (23) Leg II, trochanter removed (right, antiaxial aspect).

length, smooth. Four pairs of areae porosae with sclerotized borders. Area porosa Aa situated anterolaterad to seta lm; A anteromedial to seta lp; A and A situated 1 2 3 anterolaterad to setae h and h, respectively. Lyri®ssures ia, im, ih, ips well 2 1

developed; im situated anterior to area porosa A; ia, ih and ips visible only in 2

lateral view; ip inconspicuous. Lateroabdominal gland opening gla situated posterolateral to im (®gures 17, 19).

Lateral aspect. Relatively robust species in lateral view, dorso-ventral thickness postgenital transect 225±234 (230) m m. Exobothridial region and lateral part of podosoma well granulated. Region between lamella and pedotecta I and II with a few muscle sigillae. In lateral aspect, lamella relatively narrow, sublamella well developed, and prolamella reaching to the insertions of the rostral setae. Carina circumpedalis rather long, but rarely very short, not reaching to the lateral margin the ventral plate. Lyri®ssures ih and ips situated very close to each other (®gure 19). Gnathosoma   . Subcapitulum, palps and chelicerae normally developed for the genus. Hypostomal surface smooth, hypostomal setae h and maxillar setae m short and thin.

Epimeral region. Surface of epimeral region with a few round muscle sigillae. Apodemata apo.2, apo. sj and apo.3 well developed, rather long. Epimeral setae medium in length, slender; seta 1c slightly longer than the others. Setal formula of epimerata: 3-1-3-3. Pedotecta I and II relatively small, blunt at tip, outer margin rounded. Discidium well developed, but very narrow, bearing seta 4 c. Carina circumpedalis well developed, but sometimes not reaching to the lateral margin of the ventral plate (®gures 18, 19).

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 twice as long as the length of the former. Four pairs of genital and one pair of aggenital setae, rather long. Distance between bases of aggenital setae nearly equal to that between setae ad - 3. Two pairs of anal and three pairs of adanal setae; adanal setae distinctly longer 3

than anal ones; seta ad in preanal position. Adanal lyri®ssures iad situated adjacent 3

and parallel to each lateral margin of anal aperture (®gures 18, 19).

Legs. All tarsi monodactylous, dorsal surface of claws with slight serration. Tibia with two distinct apophyses for the solenidia Q and Q. Solenidia Q on tibia II 1 2

and s on genu II situated relatively posterior from their usual position. The other characters of leg setation are typical of the genus, only legs I and II are shown gures 22, 23). The formula of leg setation including famulus: I (1-5-3-4-18); II (1- -2-4-1 5); III (2-3-1-3-15); IV (1-2-2-3-1 2), and the formula of solenidia: I (1-2-2); (1-1-2); III (1-1-0); IV (0-1-0).

Material examined. Holotype and three paratypes: Mt. Khangai, District Bulgan, Arkhanga i Province, litter of larch forest ( Larix sibiricus   ), 47ss10¾N, 100ss40¾E, 24 June 1990; one paratype: Mt. Bulgan, District Erdenebulgan, Arkhangai Province, litter birch forest ( Betula plataphyll   a), 48ss20¾N, 101ss25¾E, 18 May 1996; one paratype: Mt.`Ikh Gazryn Chuluu’, District Gobi-Ugtaal, Middle Gobi Province, semidesert Caragana microphylla   1 Stipa glareosa   ), 45ss55¾N, 107ss15¾E, 20 September 1990, Leg.. Bayartogtokh. Holotype and three paratypes are deposited in the collection of the Department of Zoology, National University of Mongolia. One paratype will deposited in the Natural History Museum, London, and one paratype in the National Science Museum, Tokyo.

Remarks. Among the known species of the genus Liebstadia   , only L. longior   1252 Berlese, 1908), L. willmanni Miko and Weigmann, 1996   and L. humerata Sellnick, 1928   resemble the new species in the slender shape of the body. However, the two former species diOEer from the new species by (1) the presence of large pteromorphae; 2) the globular or globular-fusiform shape of the sensilli; (3) the short interlamellar setae; (4) the very ¯at body in lateral aspect; and (5) the smaller body size. Liebstadia elongata   sp. nov. is distinguishable from L. humerata   by (1) the absence of the dorsosejugal suture; (2) the club-shaped head of the sensillus; (3) the long interlamellar setae; (4) the posteriorly narrowed shape of the notogaster; (5) the relatively thick body size in lateral aspect; and (6) diOEerent number of setae on tarsi of legs I and III. In addition, L. elongata   sp. nov. diOEers from the two other new species described here not only in the shape of body, but also in the presence of two distinct apophyses on tibia I (for the solenidia Q and Q) and more posterior situation of

1 2 solenidia Q and s of tibia II and genu II, respectively.

Etymology. The speci®c epithet,`elongata ’ refers to the relatively long and slender body shape.