Sphodros niger

(Hentz, 1842)

Black purse-web spider, Black Purseweb Spider

Sphodros niger is a mygalomorph spider native to northeastern North America. Males reach approximately 11 mm in body length (29 mm with legs extended) and possess distinctive chocolate-brown legs contrasting with an otherwise black body. Females were not described until 1980, 138 years after the was first named, due to their sedentary tube-dwelling . The species is listed as a special concern species in Connecticut and ranked as vulnerable in Virginia.

Sphodros niger by (c) Robert M Hallock, some rights reserved (CC BY), uploaded by Robert M Hallock. Used under a CC-BY license.

Sphodros niger by (c) aarongunnar, some rights reserved (CC BY), uploaded by aarongunnar. Used under a CC-BY license.

Sphodros niger 2 by CBG Photography Group, Centre for Biodiversity Genomics. Used under a CC0 license.

Pronunciation

How to pronounce Sphodros niger: //ˈsfɒdrəs ˈnaɪdʒər//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from other Atypidae by the combination of black body with chocolate-brown legs (other may have different leg coloration). The forward-projecting and overall dark coloration separate it from other mygalomorph in its range. Males are most commonly observed due to their mate-searching .

Images

Habitat

Dry sandy or rocky woodland areas. Shows greater selectivity than many other spider . Associated with forested environments with specific soil and substrate conditions.

Distribution

Northeastern North America, including the Eastern United States and adjacent Canada. Distribution models based on 97 occurrence records (museum, literature, and citizen science sources from 1960-2015) indicate potential suitable may exist beyond currently documented range. Listed as special concern in Connecticut; ranked vulnerable in Virginia.

Behavior

Males wander in search of mates, making them more frequently observed than females. Females are sedentary, residing in silk tubes (purse-webs) constructed in soil or substrate. The exhibits cryptic habits, with females rarely leaving their tubes.

Human Relevance

Listed as a special concern in Connecticut due to apparent rarity and specificity. Subject of conservation attention in multiple US states. Not known to pose significant medical threat to humans.

Similar Taxa

Other Sphodros speciesOther purse-web spiders in the may overlap in distribution; distinguished by leg coloration and specific preferences
Atypus speciesOther members of Atypidae; S. niger distinguished by black body with chocolate-brown legs versus other color patterns

More Details

Taxonomic history

Females were first described in 1980 by Gertsch and Platnick, 138 years after Hentz described the from males in 1842. This delay reflects the extreme sedentary of females and the cryptic nature of their tube .

Conservation status

The ' apparent rarity in collections and specific requirements have led to protective listings in multiple states, though comprehensive data remain limited.