Syphacia peromysci Harkema

Site of infection: Caecum and large intestine

Host species: Peromyscus yucatanicus

Localities: Aak ecological park and Kuncheil cattle ranch (Yucatan)

Specimens deposited: CNHE 12024, 12025

Comments: The specimens examined from Yucatan had characteristics described by Kruidenier et al. (1961), Quentin & Kinsella (1972) and Panti-May et al. (2018), i.e., cephalic plate rounded (males) or laterally-elongated (females) (Figure 5A); cervical alae present in both males and females (Figure 5B); deirids in females, not observed in males; males with three mamelons (Figure 5C), spicule 57 long, gubernaculum 27 long, accessory hook with ornamentation, three pairs of caudal papillae surrounding the cloacal region, and tail 60 long (Figure 5D); some females with slightly prominent vulva; eggs 93.5–95.9 long by 27.1 wide (Figure 5E), and tail 441–509.6 long.

In Mexico, Sy. peromysci has been recorded from Peromyscus sp., Peromyscus boylii (Baird), Peromyscus maniculatus (Wagner), Peromyscus melanotis Allen & Chapman in Chihuahua (Preisser & Falcón-Ordaz 2019), P. maniculatus in Hidalgo (Pulido-Flores et al. 2005), P. difficilis in Veracruz (Falcón-Ordaz et al. 2016), and P. yucatanicus in Yucatan (Panti-May et al. 2018). Our study adds two new locality records in Yucatan.