Syphacia muris (Yamaguti)

(= Enterobius muris Yamaguti)

Site of infection: Caecum and large intestine

Host: Rattus rattus

Locality: Xkalakdzonot

Prevalence and mean intensity (range): 65.3% (77/118) and 77.9 (1–816)

Specimens deposited: MLP-He 7435 and CNHE 10706

Comments: The traits presented in our specimens were in accordance with those described by Hugot & Quentin (1985), Robles et al. (2008), and Khalil et al. (2014), i.e. quadrangular cephalic plate; amphids located close to the ventral submedian papillae; slight swellings of the cuticle instate of lateral alae; males with three mamelons, spicule 50–56 long, gubernaculum 25–30 long, accessory hook without ornamentation, three pairs of caudal papillae surrounding the cloacal region, and tail 174–250 long; and females with no prominent vulva, tail 334–650 long, and eggs 73–80 long by 27–37 wide.

In México, S. muris has been reported from R. rattus in Hidalgo (Pulido-Flores et al. 2005) and Tabasco (Cigarroa-Toledo et al. 2017).

In Yucatán, this species has been previously reported from R. rattus in three localities in Mérida and in Opichén (Panti-May et al. 2015, 2017).