A NEW TROGLOBITIC PSEUDOSCORPION (PSEUDOSCORPIONES, NEOBISIIDAE) FROM ISTRIA, CROATIA

A new endemic and relict species of the genus Neobisium Chamberlin, N. mirkaci n. sp., from the Majhahlje Pit, Ćićarija (Istria), Croatia, has been described. From its phenetically close congeners, N. spelaeum Schiødte and N. stygium Beier, it is distinguished in many important respects. This new taxon is illustrated, diagnosed, and thoroughly described.


INTRODUCTION
In 2009, a sample of two cave-dwelling pseudoscorpions was collected by Matej Mirkac in the Majhavlje Pit, E-NE to the village of Gornja Nugla, Province of Ćićarija (Istria), 701 m a.s.l., Croatia.
Here are the results of the study of N. mirkaci n. sp.Table 1) Etymology.-Named after its collector, Matej Mirkac, the Croatian speleologist.
Cheliceral galea rounded and barely visible (Figs. 7 and 15).Fixed cheliceral finger with six setae, movable finger with a single seta (Figs. 7 and 15).Flagellum of eight (male) or nine blades (female; Fig. 10), only two distal blades pinnate anteriorly; other flagellar setae smooth and acuminate, diminishing in size from distal to proximal.Dentition of cheliceral finger as in Figs.7 and 15.
Manducatory process (apex of pedipalpal coxa) with five long and acuminate setae.Pedipalpal trochanter with no interior tubercle, elongated.Pedipalpal femur and tibia somewhat dilated distally; pedipalpal chelal palm widest at its midline (Figs. 3 and 11;dorsal view).Pedipalpal fingers much longer than chelal palm (Table 1).Fixed chelal fingers with 96 (male) or 93 asymmetrical, small, and contiguous teeth; movable chelal finger with 84 (male) and 82 (female) small and close-set teeth, which eventually become rounded, low, and small.Fixed chelal finger with eight trichobothria, and movable finger with four such setae.Trichobothriotaxy as in Figs. 1 and 8. Tibia IV with a single seta, basitarsus IV with three setae, and tarsus IV with three long setae (Figs. 4 and 11; Table 1).The disposition of these setae is subject to some variation.Morphometric ratios and linear measurements are presented in Table 1.

Differential diagnosis.
-The new species is easily distinguished from its phenetically close congeners, N. spelaeum Schiødte and N. stygium Beier (from Slovenia and Croatia), in many important respects.In Table 1, distinctive characters of N. mirkaci n. sp. are marked by bold numbers.*** Since the distribution center of the genus Neobisium is in Southern Europe, it is likely that it evolved there.This assumption is supported by the discovery of some Northern Mediterranean Neobisium-related genera which have primitive characteristics if compared to Neobisium.This fact therefore justifies the assumption of the great age and autochthonous origin of the proto-neobisiid stock and its species complexes in the Dinaric region.The most intensive radiation of these archaic forms took place either during the Alpine orogeny, or even before the Tertiary (Vachrameev, 1960;Ćurčić, 1988).