MICROCHTHONIUS KASTELI N . SP . ( CHTHONIIDAE , PSEUDOSCORPIONES ) — A NEW CAVE FALSE SCORPION FROM CROATIA ( DALMATIA )

A new blind false scorpion, Microchthonius kasteli n. sp., from the Mićoletova Jama Pit, Rudine, nr. Kaštel, Dalmatia, has been described. The new pseudoscorpion is different from all other congeners. It is probable that this new taxon is the remain of an old tropical soil fauna, which now inhabits the subtropical area of the Mediterranean seaside. Morphometric ratios, figures, and linear measurements of the new species are presented in detail.


INTRODUCTION
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 majority of the region's invertebrates, particularly cave arachnids, myriapods, insects, and other fauna that live underground.
In this study, a single specimen (female) of a new species of the genus Microchthonius Hadži was found by one of us (TR), carefully dissected and thoroughly analyzed.

MATERIAL AND METHODS
We examined material from a sample collected from the Mićoletova Jama Pit, Rudine, nr.Kaštel, Dalmatia (Croatia).The specimen studied represent a cavedwelling and relict form.
The aim of this study is to describe the mentioned taxon and to discuss its probable origin, historical development and interrelationships with its congeners.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 wider (Fig. 7, Table 1).Neither eyes nor eyespots are developed (Fig. 7).The anterior margin of the carapace is slightly broader than the posterior and the carapace resembles a trapezium; the minute serrations are found between the anterior and median setae.The carapace carries 16 setae and these lie in five rows.The anterior row is constituted by four se-tae, six setae belong to the 'ocular' row, two to the median row, two to the intermedian row, and only two setae constitute the posterior series.Microsetae in each preocular recess are not seen (Fig. 7).
The galea resembles a distinct sclerotic knob (Fig. 4).Immediately below of the movable cheliceral finger 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 (Fig. 4).On the fixed cheliceral finger, the first two teeth are larger, and other teeth extend proximally, diminishing abruptly in size, below those on the movable finger (Fig. 4).The movable cheliceral finger carries one seta and the fixed cheliceral finger has six long setae and two small basal and lateral setae (Fig. 4).
Apex of pedipalpal coxa has two long setae; the flagellum is nine-bladed, characteristic of the genus.
Trichobothriotaxy as in Figs. 1 and 2. Both chelal fingers are apically curved inwards.The teeth of fixed chelal finger (20) are triangular, interspaced, and occupy almost the whole length of the finger; on the movable chelal finger, the teeth ( 14) are minute 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 (Fig. 3).
Remarks.-Apart from M. kasteli n. sp., six more species of Microchthonius have been know up to now: M. rogatus (from the Isle of Brač, Croatia), M. karamani (from nr.Sveti Filip i Jakov, Dalmatia), M. dernisi (from a cave near Drniš, Croatia), M. elegantissimus (from nr.Kladnjice, Croatia), M. solentanus (from the Isle of Šolta, Croatia), and M. tragurion (from nr.Trogir, Dalmatia) (Fig. 9) (Ćurčić et al., 2012a; 2013a, c, g).From all known congeners, the new species is easily distinguished by its greater body size and all other measurements and ratios (Figs. 1 -8, Table 1).In particular, it differs from close relatives in the abdomen size, pedipalpal length, pedipalpal femur length to breadth ratio, pedipalpal chelal length to breadth ratio, pedipalpal chelal palm length to breadth ratio, pedipalpal chelal finger length to chelal palm length ratio, as well as in the form and length to breadth ratios of the leg IV podomeres (Table 1).