Placobdella costata (F. Müller, 1846)

Ahmed, Raja Ben, Romdhane, Yasmina & Tekaya, Saïda, 2015, Checklist and Distribution of Marine and freshwater leeches (Annelida, Clitellata, Hirudinea) in Tunisia with identification key, Ecologica Montenegrina 2 (1), pp. 3-19 : 8

Placobdella costata (F. Müller, 1846)

( Fig. 2D)

Diagnosis: P. costata is a flattened species. The colour of living specimens is green to brown. Seven longitudinal rows of numerous papillae are present on the dorsal face. The mouth pore is situated on the anterior rim of the cranial sucker. The latter bears two unseparated eyes. The crop has seven pairs of crop caeca and the genital pores are separated by two annuli.

Habitat: Found in small groups under rocks and under various objects such as plastic bottles. It colonizes several habitats (drainage basins, oueds and springs ...). An ectoparasitic association with the turtle Emys orbicularis was noted (Ben Ahmed & Tekaya 2009).

Distribution: P. costata was described from the Crimean Peninsula, under the name Clepsine costata . Rousseau (1912) recorded it from Southern Europe ( France, Italy and Crimean Peninsula). Soỏs (1969) recorded that this species is widely distributed in Europe (except North and Northwest Europe) and North Africa. Minelli (1979) found it in Italy (Rome, Sassari and Padova). In the Middle East, this species has been recorded from Lake Hula in Israel (Bromley 1989). Nesemann & Neubert (1999) have characterized P. costata as a Mediterranean species extending eastwards to the Ukraine, south­eastwards to Greece, Turkey and the Levant, and to the southern Arabian Peninsula. In West and Central Europe, this species was recorded from southern England, the Netherlands, Poland and Germany ( Nesemann & Neubert 1999). Recently, Sağlam (2001) collected P. costata in discharge channels at Elazig in Turkey, which correspond to the first record for the country. More recently, Vamberger & Trontelj (2007) recorded it for the first time in Slovenia.

In Tunisia ( Fig. 5C), this species was collected by Henri Gadeau de Kerville in Jendouba governorate: the valleys of el Omor (Tabarka) and El Lebga (Aïn Drahim), being identified by Blanchard (1908) as Placobdella catenigera . Ben Ahmed et al. (2008a) have recorded it in Nabeul governorate (Lebna drainage basin). In this paper, we add its presence in a new locality of this later governorate: Port Prince drainage basin (36.51162 N, 10.39404E) ; in a marsh in Jendouba governorate (36.30N, 8.47E) and in a source in El Kef governorate (36.1056N, 8.4253E) .