Dr. George-Nascimento-Failla, Mario

Two new digenean species are described from the intertidal blenny Scartichthys viridis (Valenciennes) (Blenniidae) collected off the coasts of Chile. The digenean Monorchimacradena viridis n. sp. (Lecithasteridae: Macradenininae) differs from the only known species described in the genus, M. acanthuri Nahhas and Cable 1964, in the presence of Drüsenmagen in the caeca, the location of the seminal vesicle between the testis and ovary (anterior to the testis in M. viridis n. sp.), and the pre-ovarian vitellarium. Megasolena littoralis n. sp. (Haploporidae), which is also reported from Scartichthys gigas (Steindachner), differs from the five valid species of Megasolena in that the post-caecal region (from the posterior edge of the caeca to the end of the body) is larger in M. viridis n. sp., meaning that the caeca are shortest in this species. Also, M. littoralis n. sp. is distinguished, from the other congeneric species, in a combination of characteristics, e.g., body length, suckers, pharynx, testes, hermaphroditic sac and sucker-length ratio. Sequences of ITS2 rDNA were generated for specimens of both species from various localities, indicating that it was invariant within the species. This study describes species of Monorchimacradena and Megasolena in Chilean waters, here reported for the first time off the Pacific Coast of South America.

A new species, Hemipera cribbi sp. nov., is described. This trematode was found in three intertidal fish species: Scartichthys viridis (Valenciennes) (Blenniidae), Gobiesox marmoratus Jenyns (Gobiesocidae) and Myxodes viridis Valenciennes (Clinidae) from the central and southern coast of Chile. Of 233 individuals of S. viridis from the central coast examined, 19 were infected. From the southern coast, nine individuals of S. viridis (one infected), five individuals of G. marmoratus (four infected), and 16 individuals of M. viridis (one fish infected) were examined. Hemipera cribbi sp. nov. is distinguished from the five other congeneric species mainly in the body size, being the smallest and narrowest species in the genus, reaching five times longer than wide. This is the first species of the genus described for the South Pacific Ocean off South America. ITS2 rDNA sequences of Hemipera cribbi sp. nov. from each host and locality were identified.