A NEW ENDEMIC REPRESENTATIVE OF THE GENUS RASCIODUVALIUS S. B. ĆURČIĆ, BRAJKOVIĆ, MITIĆ & B. P. M. ĆURČIĆ FROM MT. ZLATIBOR, WESTERN SERBIA (TRECHINI, CARABIDAE, COLEOPTERA)

A new species of cavernicolous and endemic trechine ground beetles, Rascioduvalis zlatiborensis n. sp., is described and diagnosed in the present paper. Also, all important taxonomic features are considered and illustrated. The type specimens of the new species were collected from the Markova (= Ršumska) Pećina Cave, village of Gornji Ljubiš, Mt. Zlatibor, Western Serbia. The new species and its congeners belong to a separate phyletic lineage of Tertiary age. All members of Rascioduvalius S. B. Ćurčić, Brajković, Mitić & B. P. M. Ćurčić are distributed in Western Serbia only, where they have gone through intense differentiation and radiation due to evolution of the karstic relief. UDC 595.762(497.11-15)

In a small sample of trechine carabids collected during 2004 from the Markova (= Ršumska) Pećina Cave, village of Gornji Ljubiš, Mt.Zlatibor, Western Serbia, a new species, Rascioduvalius zlatiborensis n. sp., is herein established and diagnosed, based on the study of two type females.The type-specimens (holotype and paratype females) are deposited in the collection of the Center for Biospeleology of Southeast Europe (Belgrade, Serbia and Montenegro).Etymology.-After Mt.Zlatibor, its terra typica.

RASCIODUVALIUS ZLATIBORENSIS
Diagnosis.-From Rascioduvalius cvijici (Jeannel) and R. stopicensis (Jeannel), this new species is easily distinguished by smaller size, different body shape, different shape of the head, different form of the eyes, number of the ommatidia, antennal size and ratios of certain antennomeres, different shape of the pronotum, different shape of the elytra, shape of the shoulders, intensity of the strial depression, position of the first pair of elytral discal setae, shape of the gonosternite, form the female genitalia, and the distance separating them (Jeannel, 1923;Jeannel, 1928;Ć určić et al. 2003) (Figs. 1-3).
Head voluminous and rounded, widening basally (Fig. 1).Frontal furrows complete and deep, especially anteriorly.Cheeks rounded, covered with tiny hairs.Eyes small, flat, reduced, lenticular, composed of 6-9 depigmented ommatidia (Fig. 2).Eyes with darkened border.An arcuated preocular furrow present.Head with two pairs of supraorbital setae.Mentum tooth bifid.Antennae moderately elongate, reaching between one third and one half of the elytra length.Antennomere II shorter than antennomere IV.Antennal articles VIII and IX oval, more than twice as long as wide (Fig. 1).
Pronotum small, wider than long, subcordate, broader than head, narrowing toward its base (Fig. 1).Anterior pronotal margin concave.Anterior angles prominent and rounded.Lateral pronotal margins rounded anteriorly and somewhat concave posteriorly.Pronotum widest in its foremost fifth.Posterior angles prominent, sharply point-66 Elytra elongated, ovoid, 1.60-1.70times as long as wide (Fig. 1).Shoulders rounded, with a sharp edge each.Elytra inconspicuously impressed in their first third or somewhat before that position (from the lateral sides), widest slightly below the mid-elytra level.Elytral apex rounded.Marginal furrows wide and deep, especially in their posthumeral parts.Elytral disc slightly convex.Surface of elytra without micropubescence.First three inner striae developed, well-depressed.Outer striae present in the form of rows of points.The first row is almost complete, while other rows are incomplete.Inner interstrial spaces convex.Elytra with two discal setae on each elytron.The first pair of discal setae situated on both fourth interstriae, at the level of about the anterior fifth of elytral length.The second pair of discal setae situated on third striae, just after the mid-elytral level.Each humerus with four setae positioned characteristically for the genus (Ć určić et al. 2003).
Legs short and thin (Fig. 1).Fore tibias pubescent apically, with a longitudinal median fissure.The first protarsal article longer than wide in females.
The appearance of the female genitalia is presented in Fig. 3. Gonocoxites IX relatively small, thickened, curved, basally totally or partly jointed with massive and rounded gonosubcoxites IX.Female paired genital structures somewhat separated.
Male unknown.

DISCUSSION
The new ground beetle species belongs to the genus Rascioduvalius, which includes two additional species from Western Serbia.Rascioduvalius zlatiborensis n. sp.clearly differs from its other congeners (R. cvijici and R. stopicensis) in many important respects, such as: smaller size (4.87 mm vs. 4.27-5.50mm vs. 5.20 mm); less elongated body; different shape of the head (rounded proximally vs. rounded submedially vs. rounded medially); different form of the eyes (lenticular vs. ellyptic vs. unknown); number of ommatidia (6-9 vs. 9-11 vs. unknown); shorter antennae; ratios of certain antennomeres (antennomeres VIII and IX more than twice as long as wide vs. antennomeres VIII and IX more than twice as long as wide vs. antennomeres VIII and IX three times as long as wide); different shape of the pronotum (subcordate, widest in its foremost fifth vs. subcordate, widest in its foremost fourth vs. narrower and more elongated, with the lateral margins less rounded anteriorly than in other analyzed species); shape of the elytra (ovoid vs. subparallel vs. almost oval, more convex laterally than in other species); shape of the shoulders (rounded vs. prominent and angular vs. rounded); intensity of the strial depression (well-depressed vs. superficially depressed vs. deeply depressed); position of the first pair of elytral discal setae (situated at a level of the foremost fifth of elytral length vs. situated at a level slightly before the foremost fourth of elytral length vs. unknown); shape of the gonosternite (wide, prominently rounded posteriorly vs. narrow, almost straight posteriorly vs. unknown); form of the female genitalia (gonocoxites IX relatively small, thickened, totally or partly jointed with massive PDF created with FinePrint pdfFactory Pro trial version www.pdffactory.comand rounded gonosubcoxites IX vs. gonocoxites IX moderately elongated, thin, partly jointed with elongated gonosubcoxites IX vs. unknown); and the distance separating them (female paired genital structures somewhat separated vs. female paired genital structures close to each other vs. unknown) (Jeannel,1923;Jeannel, 1928;Ć určić et al. 2003;present study).
Furthermore, Rascioduvalius zlatiborensis n. sp. is the second known cavernicolous species of the genus (besides the species Rascioduvalius stopicensis).
It is clear that R. zlatiborensis n. sp.(as well as the other representatives of the genus) is endemic to some mountain ranges in Western Serbia, probably representing an ancient form of Tertiary origin.This new species and its congeners belong to an old distinct phyletic lineage, which differs from all other related groups of species.