Hassalstrongylus aduncus Chandler

Hassalstrongylus aduncus (Chandler)

(= Longistriata adunca Chandler; = Longistriata norvegica Dikmans)

Site of infection: Small intestine

Hosts: Rattus rattus and Sigmodon toltecus

Locality: Xkalakdzonot

Prevalence and mean intensity (range): Rattus rattus 1.7% (2/118) and 3 (2–4), S. toltecus 94.7% (18/19) and 372.8 (13–1037)

Specimens deposited: MLP-He 7431, 7442 and CNHE 10713

Comments: The specimens collected in Yucatán presented morphological characteristics in accordance with the original description given by Chandler (1932) for the parasites of S. hispidus and the re-description by Durette- Desset (1972) of parasites from the same host, i.e. 23 cuticular ridges in the synlophe at midbody; subsymmetrical bursa, with two well-developed lateral lobes and small dorsal lobe, bursal pattern type 1-4 with ray 2 well separated and divergent from the ray 3; dorsal ray with a thick trunk at the base and forking in the shape of an inverted U; and spicules 302–639 long with sigmoid tips.

In México, H. aduncus has only been reported from S. hispidus in Hidalgo and Jalisco (García-Prieto et al. 2012). This is the first record of H. aduncus from S. toltecus and from R. rattus in this country.