The nematode Hysterothylaciwn winteri Torres and Soto, 2004 was 1studied in detail using bright field and scanning electron microscopes.jt was recorded for the first time from the intestine of the marine fish ops boops collected from Alexandria fish market in Egypt. The morphometric data presented here are in agreement with those described by Torres and Soto (2004) for the same species. The most characteristic features revealed in this study are the papillae and amphids of the ventral lips, the ventral groove and associated bands, cuticular spine-like structures on the conical
tip of the tail, one pair of postanal papillae, 2 ilae, 6 longitudinal ridges and one pair of phasmid in the lateral part of die tail. The present findings were discussed in comparison with the previously described features of//,
winteri.