Corynosoma strumosum ( Rudolphi, 1802 ) 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 : 8-11

Corynosoma strumosum ( Rudolphi, 1802) Lühe, 1904

Figs 7–8 , Table 2

Diagnosis

Corynosoma strumosum is characterised by a body 4.90 mm long in females and 5.67 mm long in males, a robust trapezoid neck structure, spines covering most of fore-trunk, spines covering anterior third

of ventral surface of the hind-trunk, proboscis with 20 longitudinal rows of hooks in females and 18 longitudinal rows of hooks in males with 10 hooks in each row in both genders.

Material examined (see Table 1 and Fig. 1 )

FINLAND • 1 ♀; Åland, Bothnian Sea ; HWML- 39481-1158-2 • 1 ♂; Åland, Bothnian Sea ; HWML- 39481-1142-4 .

SWEDEN • 1 ♀; Stocka/Gävleborgs Province , Bothnian Sea; SMNH-162977 • 1 ♂; Östhammar / Uppsala Province, Ålands hav ; SMNH-162978 .

Figures

Fig. 7. SEM micrographs of Corynosoma strumosum from grey seals, Halichoerus grypus, in the Swedish Baltic Sea. a. ♂, whole worm, ventro-lateral view, from the Bothnian Sea, Uppland, Östhammar. b. Ventral spination on the hind-trunk of a ♂ restricted to one-third of its length only. c. Proboscis of a ♂, lateral view, showing the spineless neck and the arrangement of the hooks. d. Posterior end of a ♂ showing the extended copulatory bursa.

Fig. 8. LM micrographs of genital spines of a ♀ Corynosoma strumosum (HWML 39481–1158-2) from a grey seal, Halichoerus grypus, from the archipelago of Åland (Finland). a. Posterior of trunk. b. Enlargement of rectangular region in subfigure a.

Fig. 1. Map of sampling localities.