STEINERNEMA OREGONENSIS N-SP (RHABDITIDA, STEINERNEMATIDAE) FROM OREGON, USA

A new species in the genus Steinernema was found near Grant's Pass, Or egon. Steinernema oregonensis n. sp. can be distinguished from other S teinernema species by the length of infective juveniles, the shape of spicules, the absence of a tail mucron in first generation males, and the presence of a tail mucro in second generation males. The length of infective juveniles ranged from 816 to 1112 mu m, separating S. orego nensis n. sp. from previously described Steinernema species except S. affinis, S. anomali, S. feltiae, S. glaseri, S. neocurtillis, and S. p uertoricensis. The spicule shape and the absence of tail mucron in fir st generation male separate S. oregonensis n. sp. from these species. Ratio d and ratio e of the infective juveniles ranged from 0.4 to 0.6 and from 0.9 to 1.1, separating this new species from S. cubana, S. gl aseri, S. neocurtillis, and S. puertoricensis. DNA analysis showed tha t S. oregonensis n. sp. has distinct random amplified polymorphic DNA fragments compared to the other four Steinernema species examined. S. oregonensis n. sp. did not hybridize with closely related species : S. anomali, S. feltiae, or S. glaseri.