Theimbecillusandrufusgroups of the Spider Genusphilodromusin North America (Araneida: Thomisidae)

The 29 species and three subspecies comprising theimbecillusandrufusgroups of the genusPhilodromusin North America are described or redescribed, keyed, and illustrated. Theimbecillusgroup contains six species, of whichP.psaroniusis described as new and the female ofP.undarumBarnes is described for the first time. Therufusgroup contains 23 species and three subspecies, of whichP.cubanus,P.distans,P.schicki, andP.bimuricatusare described as new-species, andP.rufus quartusas a new subspecies.P.inaequipesBanks, 1900 is proposed as a new synonym ofP.minutusBanks, 1892, andP.michiganensisLevi, 1951 as a new synonym ofP.peninsulanusGertsch, 1934.P.mediocrisGertsch andP.minutusBanks are raised from synonymy, andP.pacificusBanks is raised from synonymy and made a subspecies ofP.rufusWalckenaer.