Synonyms and other taxonomic changes
Numbers
There are 16 species in Bugguide's range.
Identification
Based on Platnick & Shadab 1981 see the following patterns, but keep in mind pattern seems to vary quite a bit in each species:
S. angustus (two white stripes running down abdomen & meeting both anteriorly & posteriorly, carapace dark)
S. bicolor (no posterior white band)
S. capulatus (3 white transverse band, and T mark and dark posterior declivity of the carapace)
S. columbianus (very similar to montanus, anterior white band straight across not widening at sides)
S. cyaneiventris - (no anterior white band, two lateral anterior marks, two anterior white circles, one mid-dorsal unbroken white band, spotted venter)
S. decoratus - (4 white dorsal bands, anterior & 1st mid-dorsal white band meet at sides, then posterior & 2nd mid-dorsal band meet at sides also)
S. gertschi - (anterior, mid-dorsal & posterior white marks & T mark, but marks more uneven than other species & T meets anterior mark)
S. iviei - (anterior white mark shaped like "n", two white spots in mid-dorsal area, posterior white band, carapace light, very similar to montanus)
S. kastoni - just FL (anterior & mid-dorsal white bands with T mark, no posterior white mark)
S. lowelli - (anterior & mid-dorsal white bands)
S. minutus - (3 transverse white bands, anterior band wider at sides; mid-dorsal band and posterior band joining at sides, no mention of that golden coloring seen in second image which is Callilepis
S. montanus - (very similar to columbianus and the drawings in the reference show the anterior transverse band broken, but images in the guide don't match that)
S. ocellatus - (three transverse white bands and two (or 4) white spots between anterior & mid-dorsal bands)
S. stella - (white mid-dorsal mark joins large anterior white mark in the middle of the abdomen)
S. tennesseensis - (wide abdomen three white transverse bands, anterior & dorsal bands wide)

- pattern matches only - not sure on coloring
S. unimaculatus - (light colored?, two white mid-dorsal marks.. abdomen long & thin)
Range
Species in bugguide's range
S. angustus - Soutwestern USA CA to TX
S. bicolor - Texas east to FL, north to New York, Southeastern Canada (above ND)?
S. capulatus - Eastern USA & Southeastern Canada
S. columbianus - Western USA & Southwestern Canada
S. cyaneiventris - Southeastern USA
S. decoratus - Northeastern USA & Southeastern Canada
S. gertschi - just southern CA
S. iviei - Western USA & Southwestern Canada
S. kastoni - just FL
S. lowelli - TX, UT, AZ, OK
S. minutus - Eastern USA (along the coast in the north, widespread in the south)
S. montanus - Widespread in the West, more sporadic in the Eastern USA. Also in Canada
S. ocellatus - Eastern USA (to ND) & Southeastern Canada
S. stella - Arizona to TX & south into Mexico.
S. tennesseensis - ND & CO east to Virginia
S. unimaculatus - Eastern USA (coastal?) & Southeastern Canada
Remarks
".. all the species of Sergiolus are united by the presence of a fundamentally transverse abdominal color pattern (as in figs.1-4) that is highly unusual among gnaphosids.."
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