Spiders of North Carolina

Arachnids of North Carolina

Order:
Scientific Name: Common Name:		Family (Alpha):

Steatoda grossa - false black widow Theridiidae Members:			NC Records	BugGuide Account	Public View

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Female typical form with dimples

Female spotted form

Distribution Records
PDF

Vetting Levels

Adult phenology:
High Mountains (HM) ≥ 4,000 ft.
Low Mountains (LM) < 4,000 ft.
Piedmont (Pd)
Coastal Plain (CP)

Click on graph to enlarge

synonym

taxonomic_comments

Can be found in mid-20th Century literature as Teutana grossa.

species_comment

The generic name,"Steatoda," is from a greek word, meaning "tallow" or "suet," while the specific epithet, "grossa" is Latin and means "thick."

id_comments

While bearing the American Arachnological Society's recognized common name "false black widow," many specimens are not black, but a purplish-brown, with white markings. The black individuals have no red markings, unlike the northern and southern black widows that occur in NC (Latrodectus varioulus and L. mactans, respectively). Also unlike Latrodectus spp., S. grossa's abdomen is oval, rather than teardrop-shaped. Females are readily distinguished from other NC Steatoda by examination of the epigynum (see comparison figure).

total_length

Females 6-10mm; males 5.6-7mm

structural_features

silk_web

Typical tangled cobweb spider webbing in protected locations, and usually with numerous gumfoot lines.

fld_guide_descriptions

online_photos

prey

As are many theridiid spiders, S. grossa is an opportunist, and has been noted to feed on widow spiders.

predators

behavior

distribution_reference

Bradley, Richard A. 2013. Common Spiders of North America. 1st Edition. University of California Press; Berkley & Los Angeles, California, USA. p.233.

technical_reference

adult_id

1 identifiable by photo 2 identifiable by photo of specific features and/or supplementary info 3 identifiable from specimen only

abundance

distribution_comments

Typically found in coastal states.

checklist_mt_high
>=4,000 ft.

Regular	Frequent	Infrequent	Occasional	Seldom	Frequency Regular – almost always observed on given visit; >=90% chance of observation Frequent – usually observed on a given visit; >=50%<90% chance of observation Infrequent – observed less than 50% of visits; >=25%<50% chance of observation Occasional – observed on only on a small minority of visits; >=10%<25% chance of observation Seldom – not usually seen on visits; <10% chance of observation These terms refer to visits to appropriate habitats made at appropriate times of the year, making use of common sampling/observation methods. Under those conditions, Frequency refers to the chance of observing at least one individual on a given visit made anywhere within a particular region, or over multiple visits to a single site.

checklist_mt_low
<4,000 ft.

Regular	Frequent	Infrequent	Occasional	Seldom

checklist_pd
Piedmont

Regular	Frequent	Infrequent	Occasional	Seldom

checklist_cp
Coastal Plain

Regular	Frequent	Infrequent	Occasional	Seldom

habitat

in/on buildings, other sheltered locations

observation_methods

state_protection

NHP_ranks

NHP_status

status_comments

Photo Gallery for Steatoda grossa false black widow
	Recorded by: Ken Kneidel Mecklenburg Co. Comment: Penultimate instar male. Web tucked in the crack around the edge of trim around a door to a middle school.	Recorded by: Ken Kneidel Mecklenburg Co. Comment: Penultimate instar male. Web tucked in the crack around the edge of trim around a door to a middle school.
	Recorded by: Ken Kneidel Mecklenburg Co. Comment: Penultimate instar male. Web tucked in the crack around the edge of trim around a door to a middle school.	Recorded by: D. McCoy Forsyth Co. Comment:
	Recorded by: Steven Acesta Forsyth Co. Comment:	Recorded by: Steven Acesta Forsyth Co. Comment:
	Recorded by: Steven Acesta Forsyth Co. Comment:	Recorded by: Brian Bockhahn Macon Co. Comment:
	Recorded by: Brian Bockhahn Macon Co. Comment:	Recorded by: Mark Basinger Wilson Co. Comment: Specimen (female) was collected. Not sure of ID. Spider was living in same area, under same box, as Kukulcania.
	Recorded by: Mark Basinger Wilson Co. Comment: Specimen (female) was collected. Not sure of ID. Spider was living in same area, under same box, as Kukulcania.	Recorded by: Mark Basinger Wilson Co. Comment: Mature female
	Recorded by: Mark Basinger Wilson Co. Comment: Mature female	Recorded by: Michael P. Morales Cumberland Co. Comment:
	Recorded by: Michael P. Morales Cumberland Co. Comment:	Recorded by: Michael P. Morales Cumberland Co. Comment:
	Recorded by: Owen McConnell Durham Co. Comment: Female spotted form	Recorded by: Brian Bockhahn Stokes Co. Comment:
	Recorded by: Travis McLain Mecklenburg Co. Comment: https://www.inaturalist.org/observations/179155242	Recorded by: Dillon WARWICK Johnston Co. Comment: In box that had been stored in attached garage. Spm retained by D. ZEPP
	Recorded by: Brian Bockhahn Avery Co. Comment:	Recorded by: Alyssa Landreth Henderson Co. Comment: I believe this is a false black widow. Found it hiding in my garage.
	Recorded by: Alyssa Landreth Henderson Co. Comment: I believe this is a false black widow. Found it hiding in my garage.	Recorded by: Alyssa Landreth Henderson Co. Comment: I believe this is a false black widow. Found it hiding in my garage.
	Recorded by: R. Newman Carteret Co. Comment: FOMA	Recorded by: Donald Zepp Johnston Co. Comment: Crawling on guest sitting in front yard, after dark.
	Recorded by: Elizabeth Buncombe Co. Comment: Have found several this year. Shy & sweet.	Recorded by: Elizabeth Buncombe Co. Comment: Have found several this year. Shy & sweet.
	Recorded by: Elizabeth Buncombe Co. Comment: Have found several this year. Shy & sweet.	Recorded by: Brian Bockhahn Durham Co. Comment:
	Recorded by: Brian Bockhahn Durham Co. Comment:	Recorded by: R. Newman Carteret Co. Comment: FOMA
	Recorded by: R. Newman Carteret Co. Comment: FOMA	Recorded by: Brian Bockhahn Polk Co. Comment:
	Recorded by: Brian Bockhahn Orange Co. Comment:	Recorded by: Tracy S. Feldman Scotland Co. Comment:
	Recorded by: Brian Bockhahn Durham Co. Comment:	Recorded by: j.wyche Gates Co. Comment: MEMI - in wood pile at 358 Millpond Rd.
	Recorded by: j.wyche Gates Co. Comment: MEMI - in wood pile at 358 Millpond Rd.	Recorded by: Newman,Randy Carteret Co. Comment: FOMA - Fort
	Recorded by: Newman,Randy Carteret Co. Comment: FOMA - Fort	Recorded by: Chris Helms Columbus Co. Comment: LAWA - Under carport trash can at Supt. residence.
	Recorded by: Chris Helms Columbus Co. Comment: LAWA - Under carport trash can at Supt. residence.

Photo Gallery for Steatoda grossa false black widow