Mesaspis

Abstract: Phylogenetic relationships of Middle American anguid lizards of the genus Abronia were investigated using sequence data from the mitochondrial 12S ribosomal RNA gene (350 bp), cytochrome b gene (364 bp), and 30 previously described morphological characters. Emphasis was placed on species in the subgenus Auriculabronia. Both genes contain substantial phylogenetic information, with cytochrome b roughly twice as variable as 12S. All analyses (separate and combined datasets) support monophyly of Auriculabronia and, within this group, existence of a clade consisting of A. aurita, A. anzuetoi, and A. campbelli. Of three populations of A. aurita examined, one from Jalapa (eastern Guatemala) is divergent from the others for both genes and probably represents an undescribed species. The enigmatic and newly described species, A. frosti, is highly divergent from all other species examined and, unlike all other described Abronia from Guatemala, does not appear to belong to subgenus Auriculabronia. Although divergences within Auriculabronia appear relatively shallow, deeper divergences are apparent for A. frosti and for three species from Mexico (A. mixteca, A. sp. "Guerrero," and A. ornelasi). This is consistent with a temporal sequence of orogenies in the area that successively isolated these lizards in highland habitat islands. Our analysis supports monophyly of Abronia and suggests that the genera Barisia and Mesaspis may be sister to one another, with this clade being sister to Abronia.

Abstract: Entomelas duellmani n. sp. (Rhabditida: Rhabdiasidae) from the lungs and Skrjabinodon cortagoensis n. sp. (Oxyurida: Pharyngodonidae) from the intestines of Mesaspis monticola (Sauria: Anguidae) are described and illustrated. E. duellmani is the sixth species assigned to the genus and is the third species described from the Western Hemisphere. It is easily separated from other neotropical species in the genus by pre-equatorial position of its vulva. Skrjabinodon cartagoensis is the 24th species assigned to the genus and differs from other neotropical species in the genus by female tail morphology.