Glossiphonia balcanica n . sp . and Dina prokletijaca n . sp . ( Hirudinida : Glossiphoniidae , Erpobdellidae )-two new leeches from Montenegro and Kosovo

Two new leech species (Hirudinida) representing the families Glossiphoniidae (Glossiphonia balcanica n. sp.) and Erpobdellidae (Dina prokletijaca n. sp.) are described. The populations from Montenegro assigned by Utevsky et al. (2013) and Grosser et al. (2015) to Glossiphonia nebulosa Kalbe, 1964 represent an new species, here described as G. balcanica n. sp. The new species can be easily be separated from Glossiphonia nebulosa by the reduction of the papillae. Dina prokletijaca n. sp. closely resembles D. dinarica Sket, 1968 and D. montana Sket, 1968 from which can be distinguished in the combination of the small and stocky body, dorsal surface with two wide and dark paramedian longitudinal stripes and ovisacs reaching the fourth somite after the female genital pore, and curled in their entire course. A key to the species of Glossiphonia Johnson, 1816 and Dina R. Blanchard, 1892 from the Western Balkans is


Introduction
In last decade a number of data were published on leeches from the Western Balkans (i.e.Montenegro, Bosnia, Serbia, Kosovo, Albania and Mecedonia) including some species described as new for science (Grosser et al. 2007(Grosser et al. , 2014)).Recently all published and new data on the leeches from Montenegro and Serbia (including Kosovo) were summarized, respectively in two checklists published by Grosser et al. (2015a, b).However, the hirudinean fauna of the Western Balkans still remains relatively unknown taxonomically and biogeographically.The leech fauna of Montenegro includes 29 species and subspecies (Grosser et al. 2015a).On other hand the leech fauna of Kosovo is poorly documented and includes only 11 species (Sket 1968, Šapkarev 1975, Grosser et al. 2015b), so there is a good reason to assume that more species are expected to be found in the future.
In this paper, two new species of the families Glossiphoniidae (Glossiphonia balcanica n. sp.) and Erpobdellidae (Dina prokletijaca n. sp.) are described.

Material and Methods
Leeches in this study were collected by Surber net (material from Kosovo), or by hand or with pincers from the underside of roots and stones in water, as well on the banks.The external morphology (number and position of eyes, annulation, colouration, papillation and the position of genital pores) was examined on several specimens.The characters of sexual organs of Dina prokletijaca n. sp.(location, shape and extension of the genital atrium with the cornua, shape of the ovarian sacks and vasa deferentia), were checked on the three adult specimens, which show well developed sexual organs with visible oocytes inside the ovisacs.The digestive system of Glossiphonia balcanica n. sp. was examined on several particularly transparent specimens.
Measurements were taken with a ruler (in the authors opinion the precision of such measurement is sufficient, because they anyway largely depend on the body contraction).Material was examined using a stereomicroscope (Novex); photographs of the internal anatomy, mouth and annulation were taken with a microscope camera (Euromex, VC 3031C), and the photographs of the habitus and colour were taken with the camera Canon EOS 400D.

Description
Habitus: Small leeches, preserved specimens up to 10 mm in lenght and 8 mm in width, only slightly longer than width (Fig. 1A).The body dorsoventrally flattened, oval in shape and with a slightly bulbous head.Dorsally there are prominent paramedian papillae on annulus a2, further small and inconspicuous papillae irregularly arranged on dorsal surface.The ventral surface without papillae.The cranial sucker small, transverse oval, without median fold (Fig. 1C).
Colour: The colour of the dorsal surface in living specimens bright brownish (amber-coloured).Dorsally there is one pair of continuous dark paramedian longitudinal stripes; sometimes the paramedian stripes are interrupted by papillae on annulus a2.Dark or yellow spots absent, a yellow spotted sideband absent.The ventral surface one-coloured and brighter than the dorsal surface.
Eyes: Three pairs of distinct and well visible eyes in two parallel rows, the frontal pair of eyes smaller than the following two pairs, the middle pair usually largest (Fig. 1D); reductions or fusions of eyes not observed.
Digestive system: The crop has six pairs of caeca.
Etymology.The species is named after its presence in the Western Balkan.
Differential diagnosis.Glossiphonia balcanica n. sp.resembles to G. concolor (Apathy, 1888) and G. nebulosa Kalbe, 1964.With the later species, G. balcanica n. sp.share similar colour and presence of two narrow, uninterrupted dark paramedian lines on one-coloured dorsal surface.However, in G. nebulosa the stripes are sometimes absent (see : Nesemann and Neubert 1999).The both species can be separated by the colour which is bright brownish (amber-coloured) in G. balcanica n. sp.but more greyish in the specimens of G. nebulosa (compare Fig. 1E and -F).Due to the colour of body Glossiphonia balcanica n. sp. is similar to G. concolor, but the latter species can be distinguished by the presence of three pairs of dark stripes on dorsal surface with the inner paramedian one very prominent and interrupted irregularly on annulus a2 (see : Nesemann and Neubert 1999).Moreover the new species resembles G. concolor in the position of eyes.On the other hand in G. nebulosa the frontal pair of eyes is very small (sometimes reduced) while the middle and posterior pairs are often more or less fused (Fig. 1F inset).A further distinctive difference between the compared species refers to the arrangement and shape of dorsal papillae.Dorsal surface of G. balcanica n. sp. is covered by a few small irregularly arranged papillae and the prominent paramedian papillae located only on annulus a2.G. nebulosa has three pairs of prominent papillae situated on two annuli (a2 and a3) while G. concolor has a smooth body surface without prominent papillae (Nesemann and Neubert 1999).A further difference between G. balcanica n. sp. and G. nebulosa regard the median fold on the cranial sucker.This median fold, lacking in G. balcanica n. sp., is prominent in the population of G. nebulosa from Kosovo (Fig. 1F inset) but only slightly developed in the population of the later species from its locus typicus in Germany.
Remarks.Variability was found in body dimensions (5-10 mm in length, 4.5-8 mm in width); some breeding specimens with almost half of maximum size were found.
Discussion.Utevsky et al. (2013) reported Glossiphonia nebulosa from Skadar Lake and mentioned that the dorsal surface of examined specimens bears small papillae.Later on Grosser et al. (2015a) stated that the specimens from Skadar Lake clearly differ from the typical nebulosa specimens by the reduced papillae.The records of Utevsky et al. (2013) and Grosser et al. (2015a) should be ascertained to species described here as G. balcanica n. sp.The finding of a new species living sympatrically with G. nebulosa in the locus typicus clearly demonstrated that we are dealing with two separate species.The occurrence of two or more Glossiphonia species, living sympatrically in the same water bodies is not unusual.Nesemann (1990) demonstrated that association of three Glossiphonia species (G.verrucata, G. complanata, G. paludosa or G. concolor) is frequent in the Danubian regions of Austria and Hungary.
Habitat: Glossiphonia balcanica n. sp.occurs in small to medium-sized fast running waters, but also in large standing waters (Skadar Lake - Utevsky et al., 2013).At the locus typicus (spring Toplla, Kosovo) leeches were collected from March to December, with peak in winter and spring.
Distribution: Montenegro and Kosovo, widespread and common in the Mediterranean part of Montenegro.Diagnosis.Leeches with a typical Dina-annulation (quinqueannulate, b1, b2, a2, b5 < b6 (c11, c12); small and stocky leeches; the dorsal surface bright greyish with two wide and dark paramedian longitudinal stripes; ovisacs reaching the fourth somite after the female genital pore, and curled in their entire course.

Description
Habitus: Small and stocky leeches.The body is cylindrical along the entire length, with small but not raised lateral keels in the last third (Fig. 2B).The cranial sucker large with a wide mouth opening; the upper lip not Size: Small leeches.Preserved adult specimens up to 27 mm in the length and 5 mm in width.
Annulation: Leeches with a typical Dina-like annulation.The midbody somites quinqueannulate with annulus b6 only slightly broadened, more clearly broadened in the last half of the body.Annulus b6 not or only very slightly subdivided into annuli c11 and c12, other annuli not subdivided.The male genital pore situated in the furrow b2/a2, the female in the furrow b5/b6.The genital pores separated by two annuli.Colour: The dorsal surface of preserved specimens is bright greyish with two wide dark paramedian longitudinal stripes, along the entire length.The paramedian stripes forms the boundary of a bright median stripe (Fig. 2A).The ventral surface plain and brighter than the dorsal surface.
Eyes: The eyes in studied preserved specimens strongly reduced or not visible.
Sexual organs: The male sexual organs are characterized by a small atrial body with short and thick cornua.
The cornua sharply bending to the ventral side, in proximal elongated to the border of b1/b6 or on b6 of the previous somite, the apical part not coiled (Fig. 3B-C).
The paired vasa deferentia extending to the seventh ganglion after the female genital pore, after the fourth ganglion the vasa deferentia thickened and strongly curled.
The female sexual organs are characterized by the ovarian sacks (paired structure which are lying dorsally to the vas deferens) reaching the fourth somite after the female genital pore.The ovarian sacks are strongly curled in their entire course (Fig. 3A).

Etymology:
The species is named after the mountain (Prokletijea mountain range on the western Balkan peninsula, extending from northern Albania to Kosovo and eastern Montenegro) from which the type specimen was collected.

Differential diagnosis:
The new species is closely related to Dina montana Sket, 1968 andD. dinarica Sket, 1968.The both species live in the same area as the new species (see: Grosser et al. 2015a, b).From the latter species Dina prokletijaca n. sp.differs in the size, reaching approximately the half of size of D. dinarica.The latter species has more pronounced annulation than the new species with all annuli apart from b6 may be subdivided.Further difference includes the extension of the ovarian sacks which is one somite shorter in D. dinarica.Due to the shape and extension of the sexual organs Dina prokletijaca n. sp.resembles D. montana Sket, 1968, a species originally described from the Prokletije Mountain (Sket 1968).The latter species differs from Dina prokletijaca n. sp.in: 1) slender and dorsoventrally more flattened body, dorsal surface smooth without papillae, 2) cranial sucker elongated with a small mouth opening (Fig. 3C right), 3) the dorsal colour of freshly preserved specimens of D. montana is very dark greyish to brownish, therefore the dark paramedian stripes are not clearly visible, and 4) eight eyes visible, occasionally only a single eye absent.
Dina lineata (O.F. Müller, 1774) a medium sized to large leeches can be easily distinguished from D. prokletijaca n. sp., by the slender body with a small mouth opening.The small sized Dina lineata lacustris Sket, 1968 differs in the female genital pore shifted on b6 (in the middle or at the end of the annulus), never in the furrow b5/b6 (Sket 1968).
The reduction of visible eyes make the new species similar to Dina minuoculata Grosser, Moritz & Pešić, 2007, a medium to large yellow spotted leech known from the mountain area of Montenegro (Grosser et al. 2007).The latter species is characterized by the conspicuous papillae and less curled ovarian sacks.Moreover, the reduction of pigmentation of eyes is much further progressed in D. prokletijaca n. sp.
Variability.A strong variability was observed in eyes and extension of ovarian sacks.In the holotype eyes are not visible; in some young specimens a small single eye can be present.The extension of ovarian sacks also vary; in one specimen the both ovarian sacks reaches the ganglion of the fourth somite, in another specimen the ovarian sacks extends to the furrow b6/a1 between the third and fourth somite after the female genital pore.However, intermediate position was also found and in one specimen, the right ovarian sack reaches to the ganglion of the fourth somite but the left one reaches to the furrow b5/b6 of the third somite after the female genital pore.
Habitat: Dina prokletijaca n. sp. was collected in rheocrene springs in deciduous forests dominated by the common beech (Fagus sylvatica L.).The leeches were collected from March to December, with peak in spring.
Key to the Dina-species from the Western Balkan (excluded the species of the so-called Dina ohridanacomplex which contains species endemic to lake Ohrid, characterized by genital pores separated by three annuli)