This southeastern vine ("sawbrier") occurs in a wide range of habitats (F, FNA 26, W), but in Ky. it is most common on dry calcareous sites. The northern limit of its range is relatively abrupt, perhaps reflecting its evergreenness, which is more pronounced than other Smilax species in Ky. S. bona-nox is restricted to southern regions within Ill. and Ind., and remains virtually unknown in Ohio, W.Va. and Penn. (K). In Ky. there are virtually no records north of the Kentucky River Palisades, except for colls. from HARR and PEND (KY), plus sight records of B from CART and ROWA. Compared to other greenbriers of Ky., bona-nox is distinct in its strictly 1-seeded berries (versus 1-3), though berries are similar to hispida in their relatively small size and less glaucous surface (Wilbur 1967; above refs.). Leaves generally have more gradual tapering to the apex (widest at 10-30% above base versus 30-50%), and often more dilated bases (somewhat deltoid to hastate); lower surfaces dry to a deep brownish ("tan") color with a raised network of veins; margins have pronounced pale translucent thickening, often with scattered spine-like projections (especially in shorter 'juvenile' shoots). Juvenile leaves are usually mottled (perhaps camouflaged from herbivores) with paler to whitish patches, sometimes strongly so (versus less mottled in glauca and not at all in the others). Petioles are often stellate-scurfy when young. Stems are terete to bluntly 4-angled, with flattened prickles at nodes. Lower internodes tend to have denser and stouter prickles, plus rough pustules that initially bear stellate hairs. S. bona-nox is a highly variable species. Several segregates have been suggested, but there has been little definitive study. There is also much potential confusion with the closely related southern species, S. auriculata Walt.; compare treatments of W and FNA.