Liebstadia willmanni, Miko, L. & Weigmann, G., 1996

Miko, L. & Weigmann, G., 1996, Notes on the genus Liebstadia Oudemans, 1906 (Acarina, Oribatida) in Central Europe, Acta Musei Nationalis Pragae, Series B, Historia Naturalis 52, pp. 73-100 : 78-86

Liebstadia willmanni sp. nov.

Figs 3-9; Pl. 1, figs 1-6

The individuals of this species were collected together with another species of Liebstadia in the locus typicus of Protoribates pannonicus WILLMANN, 1951. It was not clear which, of the two species found is Willmann's P. pannonicus . The material of Willmann likely contained hoth species, but for the description of Protoribates pannonicus a more robust one was chosen, with seta lp removed from area A1 and with 4 pairs of areae porosae (as can be seen on the figure in the original description). The other, flat species with 3 pairs of area porosae differs from the similar L. humerata SELLNICK, 1928 and L. longior (BERLESE, 1908) by several characters (development of pteromorphs and shape of sensillus). Therefore this species is considered a new, undescribed species of Liebstadia .

A similar species with identical main characters was also found in our material from Slovakia. The slight differences observed are not regarded to be of specific character. The new species is also described on the basis of material from Austria and Slovakia.

Liebstadia longior sensu KUNST (1971, fig. 154) differs from Liebstadia longior , as redescribed above, by the shapes of the pteromorphs and of the sensillus, and most probably it is conspeeifie with this new species.

Material studied:

- 5 females and 4 males from Austria, Brunnlust Natural Reserve (near the Moosmühle), wet meadow, in bults of Juncus and Phragmites (locus typicus of Liebstadia pannonica , see below). 15. 6. 1992, leg. L. Miko and A. Bruckner - locus typicus. Holotype and 3 paratypes in the collections of the authors (L. M. holotype and 1 paratype, G. W. 2 paratypes), 1 paratype in the collection of Staatssammlungen Munich.

- 2 females and 1 male from Slovakia, Dreveník natural reserve (near the Spišské Podhradie, East Slovakia), sample Nr. LM-332-90, soil and litter under Corylus in rocky clough. 4. 10. 1990, leg. L. Miko.

Description of the adult

Diagnosis:

Small to medium large, flat species with typical characters of Liebstadia (lamellar complex, monodactyl, areae porosae). Sensillus with short stalk and fusiform or globular-fusiform head. 3 pairs of areae porosae present on notogaster: A2 and A3 fused (rarely fusion incomplete, or A2-A3 not fused, in this case areae situated very near to each other). Seta lp much nearer to area AI than seta h3, ratio lp-Al to h3-A1 over 3. Pteromorphs well developed, clearly bent downwards and reaching or nearly reaching the Upper level of acetabula in lateral view. Ventral side with microstriate sculpture, adanal shield with more or less visible sclerotized band laterally of anal plates.

The immatures are unknown.

General characters:

Length of females 355-439 µm (average 387 µm, n=5), width 159-214 µm (average 179 µm). Measures of males: 352-384 x 160-189 µm (average 365x171 µm, n=4). Length:width ratio 2- 2.3:1. Dorsoventral thickness in postgenital transect 95-125 µm. Length:dorsoventral thickness ratio 3.3-4:1 (usually about 3.8:1). Colour Light yellowish brown to dark yellow. Cuticle smooth, ventrally with microstriate sculpture. Sublamellar, subbothridial and acetabular region with fine granular cerotegument.

Prodorsum:

General view typical of Liebstadia . Rostrum rounded, distinctly protruding. Lamellar complex typically developed; lamella (lamellar ridge) joins the insertions of setae in and le, ventrad curved. Sublamella long, narrow, joined to ventral part of bothridial complex. Prolamella present, reaching the ro insertions. Tutorium abseilt, or present as an indistinct line. Bothridium comparatively small, only slighfly overlooking the anterior border of notogaster or fully covered (form "A", see figs 3b, c). Posterolateral scale of bothridium absent. Bothridial lamellae between lamella and sublamella (bl, bl') short and weakly developed or indistinet. Sensillus comparatively short (about 35-40 µm), with very short stalk (10-12 µm). Head of sensillus subglobular or fusiform-globular in dorsal view, but clearly fusiform in lateral view, about 25-28 µm long. All prodorsal setae except exobothridial seta long, with brisfies (in 30-50 µm, le 40-60 µm, ro 30-40 µm), lamellar setae reaching the rostrum. Sublamellar area porosa present, sometimes indistinet.

Notogaster:

Elongated, anteriorly with subparallel lateral sides. Anterior border strongly curved, protruding to the prodorsum, indistinet. Pteromorphs immovable, well developed, posteriorly reaching to 1/3- 1/2 of notogaster length, distinctly bent downwards and rounded. 10 pairs of medium long notogastral setae present (21-28 µm). 3 pairs of areae porosae present; Aa subequal or slightly smaller than A1. A2 and A3 fused. forming a Single, slightly elongated and sometimes comparatively large area porosa. Rarely the fusion of A2 and A3 is incompletc or interrupted (1 case unilaterally in our material). In this case areae A2 and A3 are near eachother. Area A1 very close to seta lp; ratio of distances lp-A1:h3-A1 ranking from 1:2.5 to 1:7.5 (usually about 1:5). All lyrifissures present in usual place, notogastral gland pore visible. Posterior border of notogaster slightly angulated and narrowed in posterodorsal view (fig. 4c).

Gnathosoma:

With usual characters of superfamily. Rutellum (fig. 6c) large, robust, with 2 medium long setae. Adoral setae long, distinctly barbed. Spine e baculiform. Chelicera (fig. 6a) robust, distally well sclerotized, with long and barbed setae, especially cha. Palp setation 0-2-1-3-9(+1). Corne double short, not inserted on apophyse (fig. 6b). Three eupathids present on palp tarsus distally except corne double.

Ventral region:

Epimeral setal formula as usual (3133), epimeral setae Short, lc somewhat longer. Apodemes not reaching to the genital aperture. A furrow between the genital plates and gnathosoma present, in light microscope indistinct. Pedotectum I small, pedotectum II distinct in ventral view. Discidium developed as a rounded blade, bearing the seta 4c. Circumpedial line long, reaching the pedotectum II. Custodial tip absent.

Genital plates comparatively small, about 47-56 µm long. 4 pairs of Short genital setae present (2+2). One pair of aggenital setae present. Distance of genital-anal aperture at least 2 times longer than genital plates. Striate longitudinal microsculpture of ventral plate is best visible in aggenital and adanal area (fig. 4b, Pl. 1, fig. 3).

Anal plates larger than genital ones, 65-68 µm long. Normal numbers of setae present in anoadanal area (2an, 3ad). Anal and adanal setae longer than other ventral setae. Posterior part of ventral plate, laterally to anal plates with more or less distinct adanal ridge, ending usually before the insertions of ad2. This ridge is in fact a thickening of cuticle, sometimes well visible in lateroventral view only. Posterior and posterolateral border of ventral plate with distinct, area-porosa-like punctulation.

Legs:

Legs monodactyl, robust, with rugose surface. Ventral lamellar carinae on trochanter III and all femora present. Ventral carina of femur I and II rounded, on femur III proximally angled and on femur IV proximally with a blunt tip (figs 7-9). Leg setation of trochanter to tarsus as follows (famulus included, solenidions in parenthesis):

leg I: 1 -5-3(1)-4(2)-18(2) (fig. 7)

leg II: 1-5-2(1)-4(1)-15(2) (fig. 8)

leg III:2-3-1(1)-3(1)-15 (fig. 9a)

leg IV: 1-2-2-3(1)-12 (fig. 9b)

Solenidions phi1(I) and phi(II) very long, setiform and tactile. Solenidion phi2(I) on a distinct apophysis. Solenidions omega1(I), omega1(II), sigma2(II) and sigma(III) ceratiform, blunt.

All other solenidions setiform.

Distribution:

Slovakia and Austria, probably also in the Czech Republic (see Kunst, 1971, as " Liebstadia longior "). Very likely, it has often been misidentified and should have a broader distribution.

Ecology:

Living in litter and organic horizon of soil in open habitats (grasslands, shrub formations etc.).

Note:

The "form A" differs generally by its slightly longer body, bothridia fully covered by anterior border of notogaster and tendency to have areae A2 - A3 not fully fused. The form is in some characters similar to L. pannonica . The body form, form of sensillus and bothridium, microstriation of ventral side (even if less distinct) and development of lamellar area are the main reasons for placing this form into the new species described here (see also the discussion).

For affinities to Liebstadia humerata (Poland) sensu Seniczak (1990), L. humerata (Spain) sensu Perez-Inigo (1993) and L. gratiosa VASILIU et CALUGAR, 1973 (Romania) see the discussion.