See Dick Walton's site here
for detailed explanations of how to ID some jumping spiders in the field.
Jumping spiders can often be identified from a photo. However, written descriptions are based on adult specimens. See the following for how much species can vary as they mature.
Bold Jumper - Phidippus audax
The most commonly encountered Phidippus. Widespread in the US & Canada.
Starting off orange & black as a juvenile, this species is usually black & white as an adult.
Phidippus audax - Females
(note the white palps)
Phidippus audax - Males
Phidippus audax - Juveniles
P. audax can be confused with males of P. regius.
P. regius ....is a strictly southeastern species. You can separate an P. audax from a P. regius by the 4 flat (not glossy) black abdominal spots, present in P. audax.
… drswanny, 24 April, 2008 - 6:33am
But the matte areas on regius are continuous and not broken into four paired rectangular spots as in audax. And this matte pattern disappears on regius by the adult molt.
… Lyn Atherton, 19 November, 2011 - 3:14am
Also males of P. regius (which can have white on the carapace) have more rounded rear white spots while P. audax has more like white dashes.
..the description of the male P. regius is for the typical male. If you look at the images of specimens that are listed as "undescribed", you'll see a great deal of variation on atypical specimens. Don Cadle, 9 Sept., 2013
Juvenile - note the band on the front of the carapace which is a juvenile P. regius trait
Salticus scenicus - Zebra Jumper
Throughout southern Canada and the entire United States, though doesn't appear to be common in the south.
Gray Wall Jumper (Menemerus bivittatus)aurantius
When Leg III is longest it's Habronattus.