A NEW CAVE PSEUDOSCORPION FROM DALMATIA — MICROCHTHONIUS TRAGURION N . SP . ( CHTHONIIDAE , PSEUDOSCORPIONES )

A new eyeless pseudoscorpion, Microchthonius tragurion n. sp., from a cave in Blizna Donja (near Trogir), from the Jama kod Gomilje Pit, Dalmatia, is described. This new false scorpion differs from all other congeners. There exists a probability that this new taxon is a relict of a tropical fauna incorporating the once northern and tropical area, now representing the subtropical part of the Mediterranean. Morphometric ratios, figures and linear measurements of the new taxon are presented in detail.


INTRODUCTION
The subterranean domain consists of four main terrestrial habitats (soil, networks of microspaces between rock fragments, networks of small fissures, and caves).Of these, it is the cave habitat that has been the subject of most evolutionary studies on the Balkan Peninsula.Recent studies (Ćurčić et al., 2010a, b, c, d, e, f; 2011a, b, c, d, e, f; 2012a, b, c; 2013) have also been concerned with both edaphic fauna and that inhabiting the network of microspaces within the layer developed between the edaphic habitat and calcareous and non-calcareous bedrock.The faunistic regions or habitats were delimited according to the distribution of presumed old endemic troglobitic taxa and according to edaphobitic endemisms.These provinces presumably correspond to paleogeographic zones of Tertiary or pre-Tertiary isolation.Consequently, studies of cave and edaphic elements have proven to be remarkably important for interpreting Dinaric paleogeography.
Located centrally and to the west of the Balkan Peninsula, the Croatian Adriatic islands lie at the convergence of a large tectonic unit, namely the main mountain system that belongs to the Dinaric massif.The origin of the rich endemic and relict troglobitic fauna of the Dinarides, including arachnids and pseudoscorpions (in particular) has been largely affected by many different factors (Ćurčić, 1988;Savić, 2008).
The Dinaric karst of Croatia, including that of its islands, can be divided into four regions: lowlands, highlands, the Mediterranean Coast, and the islands of the Adriatic Sea.The Mediterranean Coast and Adriatic islands are well known as home to the ma-jority of the region's invertebrates, particularly cavedwelling insects, arachnids and other invertebrates that live underground.
In this study, two specimens (one of each sex) of a new species of the genus Microchthonius Hadži was found by one of us (TR), carefully dissected and thoroughly analyzed.

MATERIALS AND METHODS
We examined material from a sample collected from the Jama kod Gomilje Pit, v. Blizna Donja, nr. Trogir, Dalmatia (Croatia).Both specimens represent a cave-dwelling and relict form.
The aim of this study is to present a description of the mentioned taxon and to discuss its probable origin and interrelationships with its congeners.Material examined -Holotype male and allotype female from the pit in Blizna Donja, nr.Trogir, Dalmatia (Croatia), 10 February 2013, collected by Tonći Rađa.
Description -The dorsal side of the carapace reaches its maximum breadth at the level behind the 'ocular' setal row and is in general much longer than wide (Figs. 4 and 11, Table 1).Neither eyes nor eyespots are developed (Figs. 4 and 11).The anterior margin of the carapace is somewhat broader than the posterior, and the carapace resembles a regular trapezium; the tiny serrations are obvious between the anterior median setae.The carapace carries 16 setae and these lie in five rows.Four setae constitute the anterior row, six setae belong to the 'ocular' row, two to the median row, two the intermedian row, and only two setae constitute the posterior series.
A single small seta is developed in each preocular recess (Figs. 4 and 11).
The galea of the male is almost invisible (Fig. 6), while in the female it resembles a sclerotic knob (Fig. 9).Immediately below of the movable cheliceral there is an isolated tooth.The other large teeth are contiguous with a row of small teeth that end in the region below the insertion site of the galeal seta (Figs. 6 and  9).On the fixed cheliceral finger, the teeth are larger, particularly the first two, and they extend proximally, diminishing abruptly in size, below those on the movable finger.
The flagellum is nine-bladed, a characteristic of the genus.Trichobothriotaxy as in Figs. 1 and 2 (male) and 8 and 10 (female).Both chelal fingers are apically curved inwards.The teeth of the fixed chelal finger (21-22) are triangular, interspaced, and occupy almost the whole length of the finger; on the movable chelal finger, the teeth (17-20) are smaller and merge basally into a dental lamella (Fig. 1).
The measurements and morphometric ratios of the different structures as well as the tactile seta ratios are presented in Table 1.The tibia IV, metatarsus IV and tarsus IV each carry a long tactile seta (Figs. 3 and 13).
Distribution -It is likely that the distinctions of the subterranean Microchthonius pseudoscorpions are part of a pre-Miocene area of the tropical Tethys (Ćurčić, 1988).It is therefore probable that the existence of analyzed taxa in the Croatian Dinarides (including islands) presents the old constellation and is therefore in line with contemporary worldwide records (Beier, 1963;Ćurčić, 2008;Ćurčić et al., 2004, 2010a, b, c, d, e, f;2011a, b, c, d, e, f;2012a, b, c;2013;Hadži, 1937).