Twenty-one species of flatfishes belonging to five families, commonly available in the southwest (Kerala) coast of India, were examined for nematode parasites. Five species of nematodes -Hysterothylacium sp. 1 (larva), Hysterothylacium sp. 2 (larva), H. aduncrrm, Procamallarurs sp. and Philometra lateolabracis were recorded. lbenty out of the twenty-one flatfish species examined harboured one type of nematode parasite or the other. Infection with Hysterothylaciurn. sp.1 larva was more prevalent among flatfishes. Presence of zoonotic nematode Hysterothylacium sp. in about 90 per cent of the flatfish species and in 50 percent of the flatfishes of the Kerala coast demands serious attention from public health authorities. Further, infection with Philometra lateolabracis inflicted severe damages in the ovaries of flatfishes and this warrants further studies. Most of the nematode parasites are recorded for the first time from flatfishes of India.

flat fishes, nematode parasites, infection