Explanation of Names
Latin: "written". Usually indicates markings that look like writing.
Identification
Distinguishing Dolomedes vittatus from Dolomedes scriptus males can be rather tricky at times, so here's a couple physical characteristics that I use to tell the two apart:
1.) Generally, the abdominal markings of adult male D. scriptus have a more "sculptured" appearance, whereas D. vittatus have less-pronounced markings.
2.) The two dark-colored spots in the middle of the cephalothorax are almost always more robust in D. vittatus than the more narrow ones found on D. scriptus.
Here are some images from the Guide that might help clarify some of this:
Dolomedes vittatus
Dolomedes scriptus
Hope that helped a little...Brett Tyler, 31 December, 2008
The main difference between scriptus and tenebrosus is that the 'W' pattern on scriptus is outlined in white all the way across the abdomen. The pattern in tenebrosus is broken.. and it generally has less white.
Dolomedes scriptus
Dolomedes tenebrosus
Range
Dolomedes scriptus is widely distributed in eastern North America.