About Pardosa lapidicina Emerton, 1885
Pardosa lapidicina, commonly called the stone spider, is a species of wolf spider belonging to the family Lycosidae. This species is found in the United States and Canada, where it primarily occurs near water. Mature adult stone spiders are dark-colored wolf spiders measuring around 6–9 mm in length and weighing 30–70 mg when fully grown. A study by Douglass Morse of Brown University focused on the behavior of this wolf spider species. The study observed that Pardosa lapidicina is commonly found on cobble beaches above the tide line around Narragansett Bay, Rhode Island, USA, and the research investigated the species' migration patterns between different tidelines. The study recorded 30 individuals per 0.5 meters of shoreline, confirming that the species is common in this area. Migration pattern observations showed that most individuals stayed close to the beach from April through November, which are the winter months in the region. However, during warmer months, one third of the population moves with daily tides. The stone spider inhabits both open beach areas and beach areas with salt-marsh grass. It uses a sit-and-wait hunting strategy, and frequently sun-basks. Individuals are able to capture more than one prey item per day. Known prey items in the species' diet include Diptera, Collembola, and amphipods.
