Acanthocephala in amphibians (Anura) and reptiles (Squamata) from Brazil and Paraguay with description of a new species

In a survey of 1,732 amphibians and reptiles collected across Sao Paulo Province, Brazil, and 7 provinces in Paraguay, 26 species were found infected with acanthocephalans. Of 1,5 10 anurans, 14 anurans, representing I I species, were infected with cystacanths of Centrorhynchus spp. and I anuran with cystacanths of Oligacanthorhyn chits sp. Of 107 lizards, I lizard was infected with cystacanths of Centrorhynchus sp. and I lizard with cystacanths of Oligacanthorhynchus sp. Acanthocephalus caspanensis was found in 3 anurans (3 species) and Acanthocephalus lutzi in 3 anurans (2 species) and 2 snakes (2 species). The systematic position of A. lutzi cannot be resolved using presently available morphological data. Acanthocephalus saopaulensis n. sp. was found in a single individual of Bufo ictericus. The new species can be differentiated from all its congeners except A. caspanensis in having a sigmoid-shaped mate posterior end and from A. caspanensis in having a proboscis armature of 16 rows of 5-7 hooks rather than 18-19 rows of 6-7 hooks and larger eggs. The status of Acanthocephalus and Pseudoacanthocephalus continues to be problematic.