Hassalstrongylus musculi (Dikmans)
(= Longistriata musculi Dikmans)
Site of infection: Small intestine
Host: Mus musculus
Locality: Paraíso
Prevalence and mean intensity (range): 17.0% (27/159) and 23.9 (1–150)
Specimens deposited: MLP-He 7432 and CNHE 10711
Comments: The characteristics observed in our material agreed with those described by Dikmans (1935) of parasites from M. musculus, and the re-description by Durette-Desset (1974) of parasites from the same host, i.e. 24 cuticular ridges in the synlophe at midbody; slightly disymmetrical bursa with right lobe larger than left, with pattern of type 1-3-1; rays 8 stout and longer than the dorsal ray; dorsal ray divided in its second third; spicules 400–441 long with typical foot shaped tips; and absent gubernaculum.
In México, H. musculi has been recorded from Oligoryzomys fulvescens (Saussure) O. couesi, and O. melanotis in San Luis Potosí (Underwood et al. 1986). This is the first record of H. musculi from its type host ( M. musculus) in this country.