* Ozyptila and Xysticus are both distinguished from either Coriarachne or Bassaniana by the lateral profile of the carapace: as Lynette mentioned, in both Coriarachne and Bassaniana the carapace is roughly flat all the way from front to back. The side profile of the carapace for Ozyptila and Xysticus, on the other hand, will be higher near the front and will drop down near the back at around coxa three. Coriarachne and Bassaniana maintain roughly the same level height from front to back.
So, the order of things to check when separating Xysticus, Ozyptila, Coriarachne and Bassaniana is:
1) Check carapace flatness first, to separate Coriarachne and Bassaniana from Ozyptila or Xysticus
2) Then, check the ventral macrosetae on tibia I and femur I length/width ratio to separate Xysticus from Ozyptila.
Ozyptila: - no more than 2 pairs of ventral macrosetae on tibia I .... femur I length-to-width ratio is about 3:1
Xysticus: - 3 to 4 pairs of ventral macrosetae on tibia I .... femur I length-to-width ratio is about 4:1
As for separating Coriarachne from Bassaniana, Lynette knows more about that than I do. :)
Anyway, that's how I've been separating these genera, using the information from Spiders of North America, Ubick et al. (2005) page 247. ~ John Sloan 2 Aug. 2009
O. americana -
O. arctica -
O. beaufortensis -
- drawings and written descriptions.
O. conspurcata -
O. creola -
O. curvata -
O. distans -
O. formosa -
O. georgiana -
O. gertschi -
- Drawings and written descriptions.
O. hardyi -
O. inglesi -
O. monroensis - In the eastern U.S.
O. pacifica -
- Image of male and female.
O. praticola -
- images of males and females.
O. sincera -
O. sincera canadensis -
O. sincera oraria -
O. trux - Canada (introduced)
O. yosemitica -