ON THE DIVERSITY OF IRANIAN LEECHES (ANNELIDA: HIRUDINEA)

Some provinces of Iran were investigated with respect to their aquatic invertebrates during two expeditions. Results of investigating the systematics of leeches (Annelida: Hirudinea) are presented in this paper. Twelve species of leeches are recorded, four of which are new for the country. UDC 595.143(55):591.9


INTRODUCTION
In 2003 and 2005, the second author carried out two expeditions in Iran.The first included Kerman, Mazandaran, Markazi, Esfahan,Yazd, Hamedan, Chahar Mahal, and Bakhtiari Provinces, while the second was in the Provinces Khorrasan, Markazi, Lorestan, Kermanshah, and Mazandaran (Fig. 1).The leech fauna of Iran is poorly known (B e n n i k e, 1940; L u k i n, 1976; S a w y e r, 1986), and special identification keys for the region are missing (A. A. Gholami/Tehran, pers.comm.).However, in view of the geographical location of Iran, a very rich fauna of leeches should be expected.
For each of the species collected, the new locality records are given, followed by the global pattern of distribution.In addition, taxonomic notes are provided for some species.

MATERIAL AND METHODS
Leeches were collected by hand or with pincers from the underside of roots and stones in the water, as well as on the banks.The collected leeches were first transfered into 10 % ethanol, after which they were washed to remove the mucus and preserved in 70 % ethanol.The material is deposited in the authors' collections.
Remarks: This specimen of the genus Dina could not be clearly assigned to any of the known species.Distribution: Known from the eastern Mediterranean region and in the Near East where it is abundant (Sawyer, 1986, Nesemann & Neubert, 1999).New for Iran.Distribution: This species is known from the southwestern Mediterranean part of the Western Palaearctic.Bennike (1940) records specimens from Western Iran resembling Dina lineata lineata (Nesemann & Neubert, 1999) Nesemann(1993) and Nesemann & Neubert (1999) mentions three dark longitudinal stripes (one pair of paramedian stripes and one median stripe) on the dorsal surface as being characteristic.Specimens with this coloration are common in the Near and Middle East.Nesemann(1993) assigned them to Dina stschegolewi because the locus typicus is in the aforementioned region.However, it is more likely that they belong to a new species.
Distribution: This species is widespread in the Palaearctic region.New for Iran.

CONCLUSIONS
These new data are based on a rather small collection of leeches, but they allow an interesting insight into the leech fauna of the study area.The Iranian leech fauna belongs to the Palaearctic region and is characterized by the presence of European species (S a w y e r, 1986).Most of the species found in Iran on these two expeditions are also recorded in Europe.S a w y e r (1986) subdivided the Palaearctic region into two zoogeographical zones: Boreal subregion and the Ponto-Mediterranean subregion.The Ponto-Mediterranean subregion is characterized by the following species: Limnatis nilotica, Batracobdella algira (Moquin-Tandon, 1846), and Dina sp.Dina is a very common genus in Iran and was dominant in material collected during the two expeditions (Table 1).

Fig. 1 .
Fig. 1.Map of the study area in Iran.
Material examined: Mazandaran Province, city of Nowshahr (on the Caspian sea, 37°17'N 50°07'E), pond, 6 m a.s.l., 18.06.2005,leg.V. Pešić, four specimens.Remarks: Hirudo sp. is a new species.The description by T r o n t e lj and U t e v s k i (2005) is in press.This leech will be named Hirudo orientalis.New for Iran.Mediterranean species.Further, there are records from the Ukraine and the Crimean Peninsula, the Near and Middle East, the Arabian Peninsula and East Africa (N e s e m a n n and Neubert, 1999).Remarks: The Iranianspecimens of Limnatis are still assigned to L. nilotica.Probably, L. nilotica can be subdivided into several species in the future.First genetic investigations support this idea (P.Trontelj, pers.comm.).After the clarification the taxonomy of Limnatis the material from Iran will have to be verified once more.Lorestan Province, stream nearKhorramabad, 24.06.2005,leg.V. Pešić, one specimen; Markazi Province, Cheshmeh Shater on Arak to Khomein road (8 km after Arak, ca.34°08'N 49°45'E), ca.1700 m a.s.l., 22.06.2005,leg.V. Pešić, three specimens; Markazi Province, Varcheh spring in Emamzadeh Varcheh village (in Arak to Khomein road, ca.20 km to Khomein, ca.33°49'N 49°55'E), ca.1700m a.s.l., 22.06.2005,leg.V. Pešić, 1 specimen.
Distribution: L. nilotica is a circum-

Table 1 .
Dominance of leeches in matherial collected during two expeditions in Iran in 2003 and 2005