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Two spiral nematode species, Helicotylenchus dihystera (Cobb, 1893) Sher, 1961 and Scutellonema brachyurus (Steiner, 1938) Andr(a)ssy, 1958 were recovered from soil samples collected from turfgrasses in North Carolina and South Carolina, USA during 2011 ~ 2012 and from previous collections.Two species are differentiated from each other by body length (609 ~ 693μm in H.dihystera vs 720 ~ 907 in S.brachyurus), lateral field (no areolated in H.dihystera vs areolated from the anterior to the excretory pore and at phasmids in S.brachyurus), stylet length (23.0 ~ 26.5μm in H.dihystera vs 27.2 ~ 28.4pm in S.brachyurus), spermatheca (usually conspicuous and without sperms in H.dihystera vs no spermatheca or sperms in S.brachyurus) , phasmid (small, 5 ~ 11 annuli anterior to level of anus in H.dihystera vs large,just pre-anal in S.brachyurus), tail (convex-conoid to a narrow terminus which usually may form a slight ventral projection, 6 ~ 12 annuli in H.dihystera vs tail broadly rounded, 8 annuli between anus and tail tip, no projection in terminus in S.brachyurus).The morphological and morphometric characteristics of these species are presented.