Spiders (Arachnida: Araneae) from the Sky Island Mountains of Sonora: A survey at Rancho Las Playitas, Arizpe and Bacoachi with new species records for Mexico

This study investigates the diversity, abundance, and composition spider communities prehensive species list for the Sky Island Mountains of Sonora, compiled from recent surveys. Spiders were collected using three methods: visual searching, foliage beating, and pitfall trapping. We report 29 new distributional records for spider species, four of which are new country records for Mexico and 25 for the state of Sonora. Additionally, we describe and image the vulva of Calilena arizonica Chamberlin & Ivie, 1941 for the first time, and provide images of 28 additional species. Our findings expand the known spider diversity in the region and reveal richness and compositional pattern in Rancho Las Playitas that exhibit low similarity to other spider communities from arid environments.