ON TWO NEW CAVE SPECIES OF PSEUDOSCORPIONS (NEOBISIIDAE, PSEUDOSCORPIONES) FROM HERZEGOVINA AND DALMATIA

A careful analysis of samples of pseudoscorpions (Neobisiidae, Pseudoscorpiones) from two underground habitats, one near Trebinje (Herzegovina) and the other from the National Park Paklenica (Croatia), has yielded two species of the genus Roncus L. Koch new to science, Roncus tribunus n. sp. and R. argyrunti n. sp. Both new species are described thoroughly, illustrated, and diagnosed. Some biogeographical and evolutionary characteristics of the two taxa are briefly discussed.


INTrODuCTION
There exists no deeper karst than that situated in Dalmatia, Herzegovina and Montenegro.Not a drop of water remains long on the surface; all water sinks through various subterranean passages -potholes, ponors, fissures and crevices.Most water drains towards the Neretva river, while some drains towards the Zeta and Morača rivers and Lake Skadar (Cvijić, 1926;Gavrilović, 1974).The study of pseudoscorpions in such underground habitats, a fauna whose composition is the result of a long and complicated history, enables us to evaluate the importance of the influence of long geomorphological isolation on the development of cave biota.Because of the age of these caves, different groups of pseudoscorpions have enjoyed the possibility of uninterrupted development and autochthonous differentiation.Such long isolation must have directed evolution towards greater ecological differentiation within the framework of the cave system (Ćurčić, 1988).
In studying some Balkan pseudoscorpions from two small collections, we concentrated on two species belonging to the genus Roncus L. Koch (Neobisiidae).The former was represented by two females and one female, the latter by a single male.The specimens of Roncus from Herzegovina turned out to be a new species, Roncus tribunus n. sp., and a specimen of the genus from Croatia represents another new species -Roncus argyrunti n. sp.In this paper, both species are thoroughly described, diagnosed, and illustrated.In addition, some taxonomic, biogeographical, and evolutionary traits are briefly discussed.
ed on slides in gum chloral medium (Swan's fluid); they are deposited in the collections of the Institute of Zoology, Faculty of Biology, university of Belgrade, Belgrade, Serbia, and the Natural History Museum in Split, Croatia.
Galea low and rounded (Fig. 8).Cheliceral palm with six setae, movable finger with one seta only (Fig. 8).Flagellum with one short proximal blade and six or seven longer blades distally, as is characteristic of the genus Roncus.Dentition of cheliceral fingers as in Fig. 8.
Tibia IV, metatarsus IV and tarsus IV each with a long sensitive seta (Fig. 2 Galea a low hyaline convexity (Fig. 16).Cheliceral palm with six setae, movable finger with one seta (Fig. 16).Flagellum with one short proximal blade and seven longer blades distally, characteristic of the genus (Fig. 14).Dentition of cheliceral fingers as in Fig. 16.
Trichobothriotaxy as illustrated in Figs. 9 and 10.Tibia IV, metatarsus IV and tarsus IV each with a long sensitive seta (Fig. 11).Morphometric ratios and linear measurements (in mm) are presented in Table 1.

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This study of pseudoscorpions inhabiting the Dinaric Karst offers further proofs of their great age and probably different origin.These species, or their stem forms, inhabited both leaf litter and humus of Dinaric forests during or even before the Tertiary.Finally, such forms represent the last vestiges of an old thermophilous and hygrophilous fauna, vestiges which found shelter in the underground domain (humus, soil, caves) of the Balkans and elsewhere (Ćurčić, 1972, 1984, 1988, 1992a, b;Ćurčić and Beron, 1981;Ćurčić et al., 1993, 2004, 2010a, b, c, d, e, f, g;2011a, b, c, d, e, f, g, h;2012a, b, c, d, e, f;2013a, b, c, d;Hadži, 1937).