Sharpilosentis peruviensis n. g., n. sp. (Acanthocephala: Diplosentidae) from freshwater catfishes (Siluriformes) in the Amazonia.

Abstract

Sharpilosentis peruviensis n. g., n. sp. is described from the catfishes Duopalatinus cf. peruanus Eigenmann & Allen (type-host) and Oxydoras niger (Valenciennes) in the River Amazon basin, Peru. The new species belongs to the subfamily Diplosentinae Tubangui & Masilungan, 1937 of the family Diplosentidae Tubangui & Masilungan, 1937 because of its possession of an unarmed trunk, a cylindrical proboscis, proboscis hooks arranged in longitudinal rows and two tubular cement glands of the same length in males. Sharpilosentis n. g. differs from the other genera of the Diplosentidae in the morphology of the reproductive system: males have a large muscular penis covered with small tubercles and the vulva of females is devoid of muscular sphincters and the cephalic ganglion is located between the second and third part of the proboscis receptacle. In addition, proboscis hooks are of three types: large hooks with simple roots in the anterior part of the proboscis, transitional 6th hook in one from two adjacent rows with bifurcated root in the distal part and small hooks without roots in the posterior part of the proboscis. A partial sequence for the mitochondrial cox1 gene is provided for this new taxon. The taxonomic composition of the family Diplosentidae is discussed.