Morphological and molecular data reveal a new species ofLueheia(Acanthocephala: Plagiorhynchidae) fromTurdus migratorius(Turdidae) in central Mexico and its phylogenetic implications within the family

Members of the genusLueheiaTravassos, 1919, are endoparasites of birds, particularly passerines, throughout the Americas. Adults ofLueheiasp., (Plagiorhynchidae Golvan, 1960; Porrorchinae Golvan,1956) were recovered from the intestine of the American robin (Turdus migratorius phillipsiBangs) in Mexico City, and two other species of acanthocephalans identified asPorrorchis nickoli,(Plagiorhynchidae: Porrorchinae) Salgado-Maldonado and Cruz-Reyes,2002andCentrorhynchus microcephalus(Bravo-Hollis,1947) Golvan,1956(Centrorhynchidae Van Cleave, 1916), were recovered from the Virginia opossum (Didelphis virginianaAllen) and groove-billed ani (Crotophaga sulcirostrisSwainson), respectively in southeastern Mexico. Specimens of three species were sequenced at two molecular markers, the small subunit (SSU) and large subunit (LSU) of the nuclear rDNA and compared with other sequences available in GenBank. Maximum likelihood and Bayesian inference analyses of the combined (LSU + SSU) dataset and each individual dataset revealed that the specimens ofLueheiasp. formed an independent lineage, which is recognized herein as a new species,Lueheia aztecaen. sp., representing the fifth species of the genus in the Americas, and the second in the Nearctic region. The new species can be morphologically distinguished from the other five species in the genus by having a cylindrical proboscis, armed with 24-26 longitudinal rows with 9-10 hooks each. Phylogenetic inference performed with the combined dataset consisting of two genes (LSU + SSU) revealed thatLueheia aztecaen. sp. andP. nickolibelonging to subfamily Porrorchinae, formed two independent lineages, indicating that the subfamily is paraphyletic.Porrorchis nickoliandC. microcephalusformed a clade with other species of the genusCentrorhynchus, suggesting thatP. nickolishould be transferred to genusCentrorhynchus, to formC. nickolin. comb. In addition, we briefly discuss the ecological associations between the members of the families Plagiorhynchidae and Centrorhynchidae.