Synonyms and other taxonomic changes
Numbers
There are two species in BugGuide's range (North America north of Mexico): P. tabulata and P. tepidariorum.
Identification
Caution is warranted when trying to distinguish between the two North American species. The only reliable way to distinguish the females is to dissect the epigynum and look at the dorsal side.
Examples of the epigyna from the dorsal aspect appear below:
P. tabulata/P. tepidariorum
Range
Parasteatoda tabulata - NY, ON, QC, NB, NF (that's from published records only; this species is very likely in other places, as well).
Parasteatoda tepidariorum - widespread all over North America.