Numbers
There are 241 species of scytodids in 4 genera. Genus Scytodes, comprising 221 species worldwide, has 9 species known to occur in the US:
alayoi, atlacoya, dorothea (velutina), globula, fusca, longipes, thoracica, univittata, and zapatana.
One former
Scytodes species (
lugubris) was synonymized with
Dictis striatipes in 2022.
(1)Identification
Carapace Patterns compared to drawings in Valerio, 1981
(2)
Carapace Patterns and leg qualities compared to specimens on BOLDSYSTEMS.org website species pages (updated:2017) (see Internet References below)
S. alayoi: ♂

♀
S. atlacoya: ♂


♀


(spotted or ringed legs, with darker joints)
S. dorothea/velutina: ♂

♀
S. fusca: ♂


♀


(clear legs, with darker joints. Can be dark enough to obscure visible patterning)
S. globula: ♂


♀


(banded and mottled legs. Carapace pattern similar to S. atlacoya, but usually darker and bolder. Overall coloration can be very dark)
S. lugubris: ♂


♀


(long-thin stripes on legs, with dark joints. May be nearly fully black in color.)
UPDATE: Moved to new taxon page Dictis striatipes
S. thoracica: ♂


♀


(thickly-banded legs)
S. univittata: ♂


♀


(clear legs, males have modified fore-legs, with two rows of spines)
S. zapatana: Gertsch and Mulaik
(3) describe this species as being similar in appearance to
S. itzana and
S. championi (which are not in BugGuide's range), but with less mottling on the sides of the carapace. BugGuide does not have any photos of
S. zapatana, but photos of
S. itzana and
S. championi can be found at
this site, in the "Los Tuxtlas" collection.
Range
Ranges listed are primarily based on BG data, as there is not much scientific literature that covers the current state of introduced species in the US.
alayoi - FL
atlacoya - Southeastern US (OK-VA-FL-TX)
dorothea (velutina) - Type specimen from TX, BG photos from CA
fusca - FL
globula - NC, SC, GA, AL, MS, FL
longipes - Florida Keys
thoracica - found in many parts of the northern 2/3 of the USA and into Ontario
univittata - TX to CA
zapatana - Type specimen from southern TX near Mexico
Internet References
~
BOLDSYSTEMS page for the genus Scytodes - These are specimens verified by DNA testing.