Family Rhytidodidae Odhner, 1926

Abstract

[Extract] Members of the Rhycidodidae Odhner, 1926 (superfamily Echinostomatoidea Looss, 1899)occur in the intestine and gall-bladder of marine turtles. The family consists of two genera, Rhytidodes Looss, 1901 and Rhytidodoides Price, 1939, each of which possesses a small lateral projection on each side of the oral sucker (also a transverse dorsal ridge in Rhytidodes). These characters distinguish the family from all others in the superfamily, except the Calycodidae Dollfus, 1929 (see Bray, Chapter 4, this volume); it differs from the Calycodidae in always lacking a ventral ridge at the anterior extremity and in the absence of oesophageal diverticula.

Looss (1901) established the genus Rhytidodes for the trematode Distomum gelatinosum Rudolphi, 1819 obtained from marine turtles (Chelonia mydas and Caretta caretta) from the Mediterranean Sea. This species was described in detail and drawn by Braun (1901a). Looss (1902a) presented a new description together with a definitive generic diagnosis. He did not indicate the exact taxonomic placement of the genus. Poche (1926) assigned Rhytidodes to the family Telorchidae [sic] Stunkard, 1924, but Odhner (1926) did not agree with this affiliation and proposed an independent family, the Rhytidodidae, for the genus, apparently based in part on the absence of a prepharynx. Others since then have accepted Odhner's family as the best home for the genus. For further details of the history of the genus Rhytidodes, see Blair & Limpus (1980).