Syphacia sp.

Site of infection: Caecum

Host: Heteromys gaumeri

Locality: Xkalakdzonot

Prevalence and mean intensity (range): 12.5% (1/8) and 10 (10) Specimens deposited: MLP-He 7437 and CNHE 10715 Comments: The morphological characteristics observed in the collected specimens belonged to Syphacia genus (Anderson et al. 2009), i.e. short and stout body; cephalic papillae near amphids; well defined esophagus bulb; and females with long tail, and elliptical eggs flattened at one side. Collected specimens were 10 females with transversal striations in the cuticule that begin in the cuticular collar; rounded cephalic plate; deirids present; lateral alae absent; body 3196–4010 long; tail 663–896 long; and eggs 90–96 long by 30.2–30.7 wide. However, new material, mainly males, should be collected to identify this taxon at a species level.

In México, three species of Syphacia have been reported ( S. muris, S. obvelata, and S. peromysci) from several small rodents (García-Prieto et al. 2012). Also, unidentified species of Syphacia have been reported from P. mexicanus and Reithrodontomys sp. in Hidalgo (Falcón-Ordaz et al. 2013; Iturbe-Morgado et al. 2017), R. rattus in México City (García-Prieto et al. 2012), H. irroratus in Morelos (Eslava-Araujo 2005), Oryzomys sp. and Peromyscus aztecus (de Saussure) in Oaxaca (García-Prieto et al. 2012), O. fulvescens and O. melanotis in San Luis Potosí (Underwood et al. 1986), and P. difficilis in Veracruz (García-Prieto et al. 2012). This is the first record of a species of Syphacia from H. gaumeri .