Castianeira crocata
(Hentz, 1847)
Red-spotted Ant-mimic Sac Spider, Red Stripe Spider
Castianeira crocata is a small -mimic spider in the Corinnidae, first described by Nicholas Marcellus Hentz in 1847. It is found in the United States. The has a black body with distinctive red markings, a color pattern that can lead to misidentification as a black widow spider despite its very different body shape. Like other Castianeira species, it exhibits ant-mimicry and .



Pronunciation
How to pronounce Castianeira crocata: //ˌkæs.ti.əˈnaɪ.rə ˈkroʊ.kə.tə//
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Black body with red markings on the surface. Body shape differs substantially from that of black widow spiders (Latrodectus), which have a more globular and lack the -mimic body proportions. Specific diagnostic features distinguishing C. crocata from are not well documented in available sources.
Images
Distribution
United States. Specific state or regional records are not detailed in available sources.
Human Relevance
Risk of misidentification as a black widow spider due to shared black-and-red coloration, potentially causing unnecessary alarm. No documented medical significance.
Similar Taxa
- Latrodectus (black widow spiders)Similar black body with red markings, but differs in body shape (more globular in Latrodectus) and lacks -mimic characteristics
- Castianeira cingulataCongeneric -mimic with similar behavioral and morphological adaptations, distinguished by banding pattern (two pale bands on in C. cingulata versus red spots in C. crocata)
Sources and further reading
- BugGuide
- Wikipedia
- GBIF taxonomy match
- iNaturalist taxon
- Catalogue of Life
- Don't Believe Everything You Read About Spiders--Or Anything Else for that Matter! | Bug Squad
- Bug Eric: Spider Sunday: Twobanded Antmimic
- Bug Eric: Woodlouse Hunter
- Bug Eric: August 2018
- Bug Eric: Spider Sunday: A Common "Indoor" Spider
- Bug Eric: Two Spiny-butts