Oligacanthorhynchidae gen. sp.

Site of infection: Small intestine

Host: Rattus rattus

Locality: Xkalakdzonot

Prevalence and mean intensity (range): 0.8% (1/118) and 4 (4)

Specimens deposited: MLP-He 7426

Comments: The characteristics presented in the specimens collected in Yucatán belonged to Oligacanthorhynchidae (Yamaguti 1963; Amin 1987), i.e. specimens of 1300–1800 long, with a trunk relatively wide in proportion to length, wider anteriorly than posteriorly; tubular proboscis armed with approximately 72 hooks arranged in spiral rows; trunk without spines; long and tubular lemnisci with several nuclei; and proboscis receptacle with thick muscular wall. Collected specimens were immature.

In México, four families of acanthocephalans have been recorded from wild mammals (i.e. Moniliformidae Van Cleave, Oligacanthorhynchidae, Plagiorhynchidae Golvan, and Polymorphidae Meyer) (García-Prieto et al. 2012). In rodents, the family Moniliformidae is the only one recorded from R. rattus in México City (Coronel- Guevara 1953) and R. rattus and R. norvegicus in Michoacán (Hierro-Huerta 1992; Tay Zavala et al. 1999). This is the first record of Oligacanthorhynchidae gen. sp. from R. rattus in México.