A new nematode species, Tanqua siamensis sp. nov. (Nematoda: Gnathostomatidae) in the rainbow water snake, Enhydris enhydris, from Thailand
Issued Date
2024-01-01
Resource Type
ISSN
00311820
eISSN
14698161
Scopus ID
2-s2.0-85205318328
Pubmed ID
39311393
Journal Title
Parasitology
Rights Holder(s)
SCOPUS
Bibliographic Citation
Parasitology (2024)
Suggested Citation
Charoennitiwat V., Thaenkham U., Tongpon S., Chaisiri K., Laoungbua P., Tawan T., Kanjanapruthipong T., Ampawong S., Chan A.H.E., Ratnarathorn N. A new nematode species, Tanqua siamensis sp. nov. (Nematoda: Gnathostomatidae) in the rainbow water snake, Enhydris enhydris, from Thailand. Parasitology (2024). doi:10.1017/S0031182024000908 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/101533
Title
A new nematode species, Tanqua siamensis sp. nov. (Nematoda: Gnathostomatidae) in the rainbow water snake, Enhydris enhydris, from Thailand
Corresponding Author(s)
Other Contributor(s)
Abstract
The genus Tanqua Blanchard, 1904, infests reptiles, particularly those inhabiting aquatic environments. This study examined a population of rainbow water snakes, Enhydris enhydris (Schneider, 1799), collected from southern Thailand. Adult nematodes consistent with Tanqua were found in the stomach. Various morphometric, meristic and qualitative morphological variables, including size, ratios, distances, cephalic appearance, the number of caudal papillae and other features, serve to distinguish the specimens from other species within the genus. In particular, Tanqua anomala and Tanqua diadema, which closely resemble our Tanqua specimens, can be differentiated by key diagnostic characteristics such as a retractable head, the distance from the anterior end to the cervical sac, the relative positions of caudal papillae and excretory pore, and the length of the uterus. Molecular analysis (COI and 18s rRNA genes) confirmed its status as a species of Tanqua, genetically distinct from Tanqua tiara, and matching the genetic sequence found in larvae of Tanqua sp. from a snakehead fish species from Bangladesh. Tanqua siamensis sp. nov. is described, supported by morphological traits, microscopic illustrations and genetic information. This study reports the first evidence of a caudal papillary pair in females. This species causes significant lesions on the stomach wall of the snake host, raising possible issues for snakes held in captivity regarding food hygiene and parasite protection.