Newspecies (Nematoda, Anisakidae) parasitizingLinnaeus (Aves, Ardeidae) in a mixed infection: morphological and molecular studies in Argentina.

Abstract

This study provides the description of a new species of Anisakidae,sp. nov., as well as the record of, both species parasitizing the Cocoi heron(Ardeidae) in a locality from the Buenos Aires Province, Argentina. An integrative taxonomic approach was used, involving phylogenetic analyses and the examination of diagnostic morphological features in the studied specimens. Among other features, the new species can be morphologically distinguished by the papillae arrangement on the male tail: whileexhibits a simple morphotype A,sp. nov. presents an intermediate morphotype B. Mainly, the possession of three adcloacal papillae pairs is a diagnostic feature separating this new species from the rest of thespecies. ThemtDNA isolates exhibitedsp. nov. as a single node and grouped close to the clade formed by both speciesandThe othermtDNA sequences showed a great concordance withThe K2P distances calculated for themtDNA isolates ofsp. nov. displayed a distance of 0.12 with, 0.13 with, and 0.16 withsp. nov. is proposed as a new taxon clearly supported by both phylogenetic analysis and distinctive morphological features that distinguish it from its congeners. The occurrence ofsp. nov. together within sympatric and syntopic conditions suggests that ecological or reproductive isolating mechanisms may be acting to maintain distinct lineages in shared environments. New records, particularly those involving intermediate and definitive hosts, will contribute to elucidating the distribution of these parasites in the Americas and potentially lead to the discovery of new species.