Theraphosoidina

Theraphosoidina was first proposed as a taxon by Robert J. Raven in 1985, based on a morphological cladistic analysis. Raven included three families: Theraphosidae, Paratropididae and Barychelidae. The group was characterized by the similar conformation of the male tibial spur (used in mating), reduced toothing of the paired claws and many labial cuspules.^[1]

Subsequent molecular phylogenetic studies upheld the relationship between the Theraphosidae and Barychelidae, but found that Paratropidae fell outside the clade.^[2][3] In 2012, it was suggested that Theraphosoidina should probably include an additional family of spiders related to Homostola.^[4] A major 2020 study of the Mygalomorphae established the new family Bemmeridae (raised from the rank of tribe) containing the two genera Homostola and Spiroctenus and included it within Theraphosoidina.^[5]

An outline version of the preferred cladogram from a 2020 phylogenetic study of the Mygalomorphae is shown below. (A node with lower support is marked ♦.) Although the precise position of the Theraphosoidina clade varied in some of the individual analyses, the clade itself was well supported.^[5]

According to Opatova et al. (2020), the clade includes the following families, one of which (Bemmeridae) was first described at this rank in their study:^[5]

• Barychelidae
• Bemmeridae
• Theraphosidae