Abstract
A new genus, Desserobdella, is described to accommodate the leech Clepsine picta Verrill, 1872 which feeds exclusively on amphibians of northern and central North America. This leech belongs to the subfamily Glossiphoniinae and therefore deposits cocoons directly onto the substrate. The genus Desserobdella n.gen. has the following diagnostic characteristics: (i) two pairs of coalesced eyes; (ii) one pair of diffuse salivary glands; and (iii) a single pair of saccular mycetomes containing prokaryotic endosymbionts. Members of the new genus are distinguished from species of the closely related genus Placobdella Blanchard, 1893 on the basis of their salivary gland structure; Placobdella species have two pairs of compact salivary glands versus the single pair of diffuse salivary glands of the genus Desserobdella n.gen. Congenitors of the new genus are Desserobdella cryptobranchii (Johnson and Klemm, 1977) n.comb., Desserobdella michiganensis (Sawyer, 1972) n.comb., and Desserobdella phalera (Graf, 1899) Jones and Woo, 1990. Desserobdella picta n.gen. et comb. exhibited a stereotypical sequence of feeding behaviours on Rana catesbeiana tadpoles which involved picking at the site of proboscis insertion prior to probing, probing, and finally blood-feeding with the posterior sucker released.