Dina punctata maroccana Nesemann and Neubert, 1994

Ahmed, Raja Ben, Bielecki, Aleksander, Cichocka, Joanna M., Tekaya, Saïda, Gorzel, Małgorzata & Harrath, Abdul Halim, 2013, Erpobdellid leeches (Annelida, Clitellata, Hirudinida) from Tunisia: New records with the description of a new Trocheta species, Zootaxa 3681 (4), pp. 440-454 : 444

Dina punctata maroccana Nesemann and Neubert, 1994

Material examined. 23 specimens collected in: Aïn Nfaja 24 km before Séjnéne, Mateur (37°02’291” N, 09°26’219” E).

Description of examined specimens. Dina punctata maroccana is very similar to D. punctata punctata . It can be clearly distinguished from the nominal subspecies found in Europe by the shape of its body which is exceptionally dorso-ventrally flattened, and by the presence of sharp lateral fringes (keels) at the post-clitellar region.

The length of preserved specimens ranges from 40–60 mm, and the width of the mid-body region is around 5 mm. The anterior sucker is longitudinally elliptical and the posterior sucker is transversally elliptical. The dorsum of living specimens is green to black in colour and is covered with prominent yellow spots ( Fig. 3 e) and by small papillae and thus appears rough. The specimens from Tunisia have more than 8 spots in a2. The ventral surface of the body is grayish ( Fig. 3 f). Each somite is divided on five annuli, the first four are short and the fifth is elongated ( Fig. 6 b). The eyes are arranged in four pairs. The gonopores are separated by two annuli.

The male reproductive system consists of numerous globular testes that form voluminous grape-like testisacs that almost reach the end of the leech body. The sperm ducts form loops that reach half distance between the ganglia XI and XII ganglion. The sperm duct has a length of 13.5 ns and thus it reaches almost XXVI ganglion. The relatively wide atrium is located at the ganglia XII and is almost 0.5 ns in length. The cornua are greatly expanded, sharply coiled and bending to the ventral side. The bursa is stout and wide ( Fig. 4 g, h, i). The female reproductive system is composed of two elongated convoluted ovisacs forming a "V". They have a length of 3.5 ns. The ovisacs start at the ¼ of the distance between the ganglia XII and XIII ganglion, and end at ¾ of the distance between the ganglia XV and XVI.

Ecology and distribution. To date D. punctata maroccana had been recorded from only one site: a brook (230 ASL) connected to a water spring, where it is abundant. The species is a semi-aquatic annelid, having similar behavior as D. punctata punctata . The leeches were also collected from moist soil, destroying the earthworm, Lumbricus sp. ( Fig. 1 h).

Dina punctata maroccana has been previously observed in Morocco and never before found in Tunisia ( Nesemann and Neubert 1994). The current distribution of this subspecies has likely been under-estimated due to its a semi-aquatic lifestyle and insufficient surveillance of its preferred habitats. Additional records can be expected, especially in the northern part of Tunisia. Thus, we recommend a certain degree of protection for this leech until further studies can establish its true status in the country.

Figures

FIGURE 1. (a – f): Some sites of leech collection in Tunisia: a: Lebna Dam; b: Aïn Essaniya, Siliana; c: Aïn Soltane, Jendouba; d: Aïn Nfaja; e: National Parc ElFaïja; f: Aïn Sidi Saleh, Bizerte; g: T. africana collected from a leaf of Quercus siber; h: Dina punctata maroccanna swallowing a worm (Lumbricus. sp).

FIGURE 3. Photos of live erpobdellid specimens.; a – b: E. testacea; c – d: D. punctata punctata; e – f: D. punctata maroccana; g – h: T. africana; D. F—dorsal view (this aspect looks brighter than the ventral one because of the uneven illumination conditions); V. F—ventral view; Scale bar: 0.6 cm.

FIGURE 4. Ventral, dorsal and lateral views of male atria of mature specimens: a – c: E. testacea; d – f: D. punctata punctata; g – i: D. punctata maroccana; j – l: T. africana; m – o: T. tunisiana n. sp.

FIGURE 6. a: Reproductive system of T. tunisiana n. sp.: atrium (at), ovisacs (o), preatrial loops (pr. l), sperm ducts (s), testisacs (t); b: anterior sucker of T. africana in the left (after Nesemann and Neubert, 1994) and T. tunisiana n. sp. in the right; arrows point to the pseudognathes; c: Schematic annulations type and gonopores of both Tunisian species of Trocheta.