Tetracelis marmorosa (Müller, 1774), Muller, 1774

Noreña, Carolina, Eitam, Avi & Blaustein, Leon, 2008, “ Microturbellarian ” flatworms (Platyhelminthes) from freshwater pools: New species and records from Israel, Zootaxa 1705, pp. 1-20 : 13

Tetracelis marmorosa (Müller, 1774)

Synonyms: Mesostoma robertsoni Graff, 1882 Mesostoma yungi Fuhrmann, 1900 Tetracelis marmorata (Bosc, 1802) Fasciola marmorosa Müller, 1774 Vortex marmoratus Diesing, 1862

Locality. Temporary, artificial pool in Hai Bar Carmel Nature Reserve.

Material. Two individuals, one with dormant or resistant eggs and one with subitaneous eggs. Squash preparations, live observations, photographs.

Ecological features. Tetracelis marmorosa forms numerous subitaneous eggs during the summer months, and produces a single resistant egg during the winter. In temperate climates (southern Europe), Tetracelis shows the two types of eggs, whereas in environments characterized by low temperatures (northern Europe), only dormant eggs are produced. This suggests the existence of two different races ( Luther, 1963; Heitkamp, 1982), a southern race and a northern race, which are also differentiated by the presence of different karyotypes ( Luther, 1963). During this study, individuals with both egg types, dormant and subitaneous, were collected in the same pool (March 2002). Therefore, the Israeli population could be included in the southern race, distributed along the Mediterranean basin.

Currently, Tetracelis marmoratum is known from Europe and Asia (light brackish lake in the region of Lob Noor, Tibet) ( Luther, 1963; Young, 1970; Gamo & Noreña-Janssen, 1998). This is the first record for Israel.