In an ongoing investigation on the helminths of amphibians in southeastern Mexico, specimens of 2 undescribed species of Haematoloechus were collected from Rana brownorum. Haematoloechus ceciliae n. sp. is morphologically most similar to Haematoloechus meridionalis, but differs in the shape of the oral sucker, in the nature of the acetabulum, and in the distribution of the glandular cells in the pharyngeal region; Haematoloechus celestunensis n. sp. closely resembles Haematoloechus floedae, but differs in the form and size of the testes and measurements of acetabulum. COI and 28S DNA sequences of both new species show high divergence compared to other species of the genus. In the phylogenetic trees, H. ceciliae appears most closely related to Haematoloechus danbrooksi and H. celestunensis to Haematoloechus veracruzanus.
Keywords: Amphibians; Digenea; Haematoloechus ceciliae; Haematoloechus celestunensis; Mitochondrial DNA; Morphological Traits; New Species; Phylogenetic Tree; Rana brownorum; Ribosomal DNA; Southeast Mexico.