Overview
- Researchers used DNA, morphology and geography to show the previously recognized Aptostichus simus actually comprises two cryptic species.
- The newly described Aptostichus ramirezae is confirmed as distinct from A. simus in a study published in Ecology and Evolution by Jason Bond, Emma Jochim, James Starrett and Hanna R. Briggs.
- Both species inhabit shrinking coastal sand dune ecosystems from central California to northern Baja California, with some populations on the Channel Islands.
- Aptostichus ramirezae appears more widely distributed across the range, whereas A. simus is now largely confined to San Diego and faces acute risk from projected sea‑level rise, development, erosion and wildfire.
- The species honors arachnologist Martina Giselle Ramirez, and the spiders’ limited dispersal and burrow‑bound life histories help explain how such cryptic diversity persisted undetected.