Academic literature on the topic 'Pseudemys nelsoni'

Polystomatids are platyhelminth parasites that infect mainly amphibians and freshwater turtles. For more than seven decades, chelonian polystomes were classified into three genera according to the number of hamuli, i.e. absent for Neopolystoma, one pair for Polystomoidella and two pairs for Polystomoides. Following re-examination of morphological characters, seven new genera were erected the past six years, namely Apaloneotrema, Aussietrema, Fornixtrema, Manotrema, Pleurodirotrema, Uropolystomoides and Uteropolystomoides. However, the polyphyly of Neopolystoma and Polystomoides on the one hand, and the nested position of Uteropolystomoides within a clade encompassing all Neopolystoma and Polystomoides spp. on the other, still raised questions about the validity of these genera. We therefore re-examined several types, paratypes and voucher specimens, and investigated the molecular phylogeny of polystomes sampled from the oral cavity of North American turtles to re-evaluate their systematic status. We show that all Polystomoides Ward, 1917, sensu Du Preez et al., 2022, Neopolystoma Price, 1939, sensu Du Preez et al., 2022 and Uteropolystomoides Tinsley, 2017 species, display vaginae that are peripheral and extend well beyond the intestine. We thus reassign all species of the clade to Polystomoides and propose nine new combinations; however, although Uteropolystomoides is nested within this clade, based on its unique morphological features, we propose to keep it as a valid taxon. Polystomoides as redefined herein groups all polystome species infecting either the oral cavity or the urinary bladder of cryptodires, with peripheral vaginae and with or without two pairs of small hamuli. Uteropolystomoides nelsoni (Du Preez & Van Rooyen 2015), originally described from Pseudemys nelsoni Carr is now regarded as Uteropolystomoides multifalx (Stunkard, 1924) n. comb. infecting three distinct Pseudemys species of North America.

This study analyzed the distribution and habitat status of 1 species of amphibian and 4 species in 1 genus of reptiles among “ecosystem-disturbing species” designated by the Ministry of Environment through the National Habitat Survey of Alien Species (2015-2021). As a result, Rana catesbeiana with 415 sites, Trachemys spp. with 513 sites, Pseudemys concinna with 174 sites, Pseudemys nelsoni with 66 sites, and Mauremys sinensis with 31 sites. Of the total habitat area of R. catesbeiana, the agricultural land area accounted for 46% and the used(urbanized/dry) area accounted for 15%. Of the total habitat area of T. spp, the ratio of agricultural land areas was 35%, and the ratio of used areas was 24%. These species were found to live mainly in reservoir areas with higher natural characteristics than in urbanized and dry areas. However, M. sinensis, which were introduced in early 2000 and have a small number of habitats, mainly inhabited agricultural land areas with high naturalness, with agricultural land areas accounting for 43% and used areas accounting for 29% of the total habitat area. Accordingly, a detailed study on the ecology and artificial release of the M. sinensis is needed.

The authors describe a case of unilateral adenocarcinoma emerging from the Harderian gland, filling the right orbital cavity of a Florida Red-bellied Turtle ( Pseudemys nelsoni ). The tumour did not produce any metastasis but presented an expansive growth and led to the dislocation and protrusion of the right eyeball. Histopathological analysis revealed the presence of numerous mitotic figures in the cellular population that made up the tumour. The tumour cells completely filled the alveoli of the gland and had a nest-like structure. The authors also emphasise the importance of the differential diagnosis of this rare pathological change in turtles. Epithelial hyperplasia of the Harderian gland’s duct, observed in animals suffering from vitamin A deficiency, can also lead to an enlargement of the eyelid, but in these cases the change usually involves both eyelids symmetrically. This is the first description of a Harderian gland adenocarcinoma in a Florida Red-bellied Turtle.