A new species of Auriculostoma (Trematoda: Allocreadiidae) from the intestine of Brycon guatemalensis (Characiformes: Bryconidae) from the Usumacinta River Basin, Mexico, based on morphology and 28S rDNA sequences, with a key to species of the genus
Por:
Ivan Hernandez-Mena, David, Lynggaard, Christina, Mendoza-Garfias, Berenit, Perez-Ponce De Leon, Gerardo
Publicada:
22 nov 2016
Resumen:
We describe a new species of Auriculostoma Scholz, Aguirre-Macedo &
Choudhury, 2004 based on several sources of information including
morphology (light and scanning electron microscopy [SEM]), sequences
of two nuclear genes, host association, and geographical distribution.
Morphologically, the new species most closely resembles Auriculostoma
astyanace Scholz, Aguirre-Macedo & Choudhury, 2004, but differs by
having deeply lobated testes and cirrus-sac extending posteriorly to
seminal receptacle level. Auriculostoma lobata n.sp. can be readily
distinguished from all the other congeners by the combination of the
following characters: testes located in tandem, testes deeply lobated,
and larger body size. A phylogenetic analysis using 28S rDNA sequences
along with those available for other allocreadiid trematodes, revealed
that the new species is a sister taxon of A. astyanace, a species
described from the banded astyanax, Astyanax fasciatus (Cuvier) in
Nicaragua. Auriculostoma totonacapanensis Razo-Mendivil,
Mendoza-Garfias, Perez-Ponce de Leon & Rubio-Godoy, 2014 from the
Mexican tetra, Astyanax mexicanus (De Filippi) in Mexico is the sister
taxon of A. astyanace plus the new species. Genetic divergence levels
for the 28S rDNA and ITS2 were estimated among the Middle-American
species of Auriculostoma infecting characiforms. The validity of the new
species is then established by reliable morphological differences, its
host association to bryconids (Brycon guatemalensis Regan), restricted
geographical distribution (Usumacinta and Lacantun River basins), and
genetic divergence levels, albeit relatively low. A morphometric
comparison between the new species and the other seven congeneric
species was undertaken and, in addition, a taxonomic key to identify the
species contained in the genus Auriculostoma, widely distributed across
the Americas, is provided.
Filiaciones:
Univ Nacl Autonoma Mexico, Inst Biol, Ap Postal 70-153, Mexico City 04510, DF, Mexico
Univ Nacl Autonoma Mexico, Posgrad Ciencias Biol, Mexico City, DF, Mexico
|