New records of helminths of Sceloporus pyrocephalus Cope (Squamata, Phrynosomatidae) from Guerrero and Michoacán, Mexico, with the description of a new species of Thubunaea Seurat, 1914 (Nematoda, Physalopteridae)

A total of 61 specimens of the Red-headed Spiny Lizard Sceloporus pyrocephalus Cope (Phrynosomatidae) collected during the breeding season (June/July 2003, 2004 and 2005) from Western Mexico were examined for helminths. The morphological characterization of the helminths found was made through light microscopy and scanning electron microscopy. Nine taxa of helminths were identified, two cestodes: Mesocestoides sp. and Oochoristica sp., and seven nematodes: Parapharyngodon ayotzinapaensis Garduño-Montes de Oca, Mata-López & León-Règagnon, 2016, Parapharyngodon tikuinii Garduño-Montes de Oca, Mata-López & León-Règagnon, 2016, Parapharyngodon sp., Physalopterinae gen. sp., Skrjabinoptera scelopori Caballero-Rodríguez, 1971, Strongyluris similis Caballero, 1938 and a new species of Thubunaea Seurat, 1914. Larvae of Mesocestoides sp. and Physalopterinae gen. sp. were found in the body cavity and digestive tract, respectively. Excluding the species of Parapharyngodon Chatterji, 1933, S. pyrocephalus is recorded for the first time as a host of the remaining seven taxa of helminths. Additionally, Thubunaealeonregagnonae sp. n. is described and illustrated as a new nematode species, parasite of S. pyrocephalus from Mexico. This new species can be differentiated from the majority of its congeners by the absence of spicules, the particular pattern of caudal papillae in males and the small ratio of oesophagus length:male total body length (0.1–0.16)

Two new species of Parapharyngodon parasites of Sceloporus pyrocephalus, with a key to the species found in Mexico (Nematoda, Pharyngodonidae)

Two new species of Parapharyngodon collected from the intestine of the Mexican boulder spiny lizard Sceloporus pyrocephalus are described. This study increases to 49 the number of valid species assigned to Parapharyngodon worldwide, 11 of them distributed in Mexico. Males of the two new species share the presence of four pairs of caudal papillae, an anterior echinate cloacal lip and the presence of lateral alae; however, both differ from each other in lateral alae extension and echinate cloacal anterior lip morphology. Females of both species have a prebulbar uterus and eggs shell punctuate with pores, characteristics shared with few other species of Parapharyngodon. Both new species differ from other congeneric species in the papillar arrangement, the anterior cloacal lip morphology, the lateral alae extension and total length/spicule ratio. A taxonomic key for the species of Parapharyngodon distributed in Mexico is provided

A new species of Hystrignathus (Nematoda: Thelastomatoidea: Hystrignathidae) associated with the Bess Beetle Passalus Interruptus Linnaeus (Coleoptera: Passalidae) from The Peruvian Amazonia

Oca, Uriel Garduño-Montes De, Sarmiento-Ruiz, Thalia, Cardenas-Callirgos, Jorge Manuel, Oceguera-Figueroa, Alejandro (2022): A new species of Hystrignathus (Nematoda: Thelastomatoidea: Hystrignathidae) associated with the Bess Beetle Passalus Interruptus Linnaeus (Coleoptera: Passalidae) from The Peruvian Amazonia. Zootaxa 5159 (3): 354-366, DOI: https://doi.org/10.11646/zootaxa.5159.3.