Helobdella Blanchard, R.1896

Sawyer, Roy T., 2024, Biology, morphology and taxonomy of a snail-feeding leech from North Carolina, USA, provisionally identified as Helobdella lineata (Verrill, 1874) (Glossiphoniidae): First evidence for extra-oral digestion in the Hirudinea, Zootaxa 5453 (2), pp. 151-182 : 153

Genus: Helobdella Blanchard, R.1896

Eyes 1 pair, well-separated and moveable relative to each other ( Fig. 9A,B ).

Species: Helobdella lineata ( Verrill, 1874) (Albemarle) , Revised.

Figures

FIGURE 9. Taxonomic significance of eyes of Helobdella compared to Placobdella. A, B, Helobdella lineata; C, Placobdella multilineata. A, Distance between eyes is maximal when the proboscis (pr) is everted. B, When the proboscis is retained internally the eyes are closer together. C, In the turtle leech P. multilineata the eyes coalesce physically at the mid-line and are not moveable relative to each other. Furthermore, each apparent ‘eye’ of P. multilineata on each side is composite, being comprised of a larger anterior eye and a smaller posterior eye. Scale bars: A, B, 0.3 mm; C, 0.1 mm.