Corynosoma Lühe, 1904

Leidenberger, Sonja, Boström, Sven & Wayland, Matthew T., 2019, Morphological observations on three Baltic species of Corynosoma Lühe, 1905 (Acanthocephala, Polymorphidae), European Journal of Taxonomy 514, pp. 1-19 : 7

Genus Corynosoma Lühe, 1904

The morphology of all three species conformed to the generic diagnosis of Corynosoma according to Lühe (1904, 1911), Van Cleave (1953), Arai (1989) and Aznar et al. (2006). The genus is characterized by a small body size, comprising a clubbed fore-trunk and a cylindrical hind-trunk. Trunk spines on the anterior and ventral surface of the fore-trunk. Neck trapezoid, short and spineless; can be retracted into fore-trunk. Proboscis subcylindrical, enlarged midway along its length or just posterior to the midpoint. Proboscis hooks arranged in longitudinal rows. Posterior 3–5 hooks in a longitudinal row without roots; all other hooks with simple, unbranched roots. Largest hooks occur on broadest part of proboscis. Proboscis receptacle double-walled. Lemnisci shorter than proboscis receptacle, broad and leaf-like. Gonopore terminal or slightly subterminal in both genders. Male reproductive system either confined to the hind-trunk or extending into posterior part of fore-trunk. Paired testes elongate-oval, partially overlapping. Six pyriform cement glands. Eggs fusiform, with relatively short polar prolongations of the thickened shell membrane, filling body cavity of gravid females. Gonopore of female sometimes covered by a copulatory cap.