Taxonomic revision of species of Haematoloechus Looss, 1899 (Digenea: Plagiorchioidea), with molecular phylogenetic analysis and the description of three new species from Mexico

Abstract

Lung flukes of the genus Haematoloechus Looss, 1899 are common parasites of anurans worldwide, but the taxonomy of the group has been confusing. In this taxonomic revision, 89 species of Haematoloechus (

Gathering morphological and molecular data for identifying two species of trematodes from the neotropical Vaillant's frog, Lithobates vaillanti (Amphibia: Ranidae) in the highlands of Chiapas, south-eastern Mexico

“…The taxonomic history and species composition of the genus Haematoloechus has been controversial because the reliable characters for species differentiation are difficult to observe and characterize; also, some species are morphologically like H. complexus , and in most of the cases it is very difficult to achieve the species delimitation only based on morphological grounds. Furthermore, the molecular data have corroborated the reliability of some characters for the differentiation of species, such as the length and width suckers’ ratio, shape of ovary and testes, and the distribution of vitellaria and uterus (León Regágnon & Topan, 2018). Haematoloechus complexus has a Nearctic distribution.…”

“…The specimens collected from the lungs of L. vaillanti were morphologically very similar to three congeneric species, that is, H. complexus , Haematoloechus caballeroi (Skrjabin & Antipin, 1962) and Haematoloechus veracruzanus León-Règagnon and Topan (2018). Our specimens share some traits with these species, such as the oral/ventral sucker ratio, ovary and testes shape, and the diagonal arrangement of uterine loops.…”

“…In the case of Haematoloechus spp., the morphological and molecular evidence unequivocally suggest that specimens of Haematoloechus from Nahá belong to H. complexus ; therefore, this is the first record of H. complexus for Chiapas state, and the second for Mexico since the species was reported in Los Tuxtlas tropical rain forest in Veracruz, a record based on the finding of the metacercariae obtained from the dragonfly Agriogomphus tumens (Velázquez-Urrieta & Pérez-Ponce de León, 2022). Previously, H. complexus had been reported in frogs distributed in Mexico, particularly in Lithobates tlaloci from Xochimilco, Lithobates montezumae from Estado de México, Lithobates forreri from Colima, and Lithobates vaillanti from Veracruz; however, in the study by León-Règagnon & Topan (2018), these authors argued that the species identification was incorrect, and they actually described these specimens as new species, namely H. caballeroi , H. occidentalis and H. veracruzanus , respectively. The taxonomic history and species composition of the genus Haematoloechus has been controversial because the reliable characters for species differentiation are difficult to observe and characterize; also, some species are morphologically like H. complexus , and in most of the cases it is very difficult to achieve the species delimitation only based on morphological grounds.…”

“…In Mexico, two species of the genus Langeronia have been previously recorded, namely Langeronia macrocirra Caballero and Bravo-Hollis, 1949, and Langeronia jimenezi Iruegas-Buentello & Salinas-López, 1989. For the genus Haematoloechus , 16 species have been reported, 12 of which are endemic (Pérez-Ponce de León et al , 2000; León-Règagnon, 2010; León-Règagnon & Topan, 2018; Velazquez-Urrieta et al , 2019; Velazquez-Urrieta & Pérez-Ponce de León, 2022). Two of these have been recorded in Chiapas, Haematoloechus floedae Harwood, 1932 and Haematoloechus sp.…”

The infection of trematodes on rice frogs (Fejervarya cancrivora)in Karawang Regency, West Java

“…Our result showed the highest prevalence of trematodes reached by Haematoloechus sp. The species belong to Haematoloechus are known in every continent except Antarctica [11]. More than 50 species of this genus have been described around the world [12].…”