Evolution of ornamentation and courtship behavior in Schizocosa: Insights from a phylogeny based on morphology (Araneae, Lycosidae)

A phylogenetic analysis for the North American Schizocosa species Was undertaken by scoring 49 morphological characters for 31 taxa representing all of the Nearctic species of Schizocosa Plus individuals that are hybrids between S. ocreata and S. rovneri. Rabidosa rabida, Allocosa georgicola and Gladicosa pulchra were used as outgroups. Three clades are recognized: a large clacle, from eastern North America (Clade A) within which is nested the S. ocreata clacle; Clade B, which includes the widespread S. avida and the western S. mccooki, and a smaller, third clade, Clade C. Sexual ornamentation occurs oil the first legs of mature males of several species within the Schizocosa and takes the form of pigmentation and or bristles primarily oil the tibia of leg I there is at least one species with bristles in each or the three main clades. Mapping the occurrence of male ornamentation oil the preferred phylogeny Suggests that ornamentation evolved 5 or 6 separate fillies and Was subsequently lost 2 or 3 times. The ornamentation is concentrated in the S. ocreata clade, a clade defined by a finger like projection oil the paleal process of the male pedipalp. Courtship behavior is known for 20 of the 31 taxa. All species studied utilize chemical communication and seismic signals for communication; some species also have distinct Visual signals. Seismic signals are produced by palpal drumming (as is seen in several species within Clade B, or by stridulation (seen in Clade A). Visual signals consisting of movements of the first pair of legs are common in species that are distinctly ornamented. This Study provides the first phylogenetic Study of a North American genus of wolf spider and provides morphometric comparisons of the North American species in Schizocosa.