Comprehensive DescriptionRead full entry
Family Penestomidae Simon, 1903
Penestomidae . Miller et al., 2010: 801.
Affinities. Removal of the Penestominae from the Eresidae HNS was justified by analysis of molecular sequence data (Miller et al. 2010). These data consistently indicated that penestomines are close to the Zodariidae HNS , and that this relationship has significantly better support than one constrained to include a monophyletic Eresidae HNS including Penestominae (Shimodaira & Hasegawa 1999) . One line of morphological evidence that could support a close relationship between zodariids and penestomids has to do with the arrangement of spigots on the anterior lateral spinnerets. Typically, the major ampullate gland spigots ( MAP ) are placed on the margin of the spinning field (e.g. see Griswold et al. 2005, fig. 49 B ) but in both zodariids (Miller et al. 2010, fig. 2 E ) and penestomids (Fig. 6 B ) the MAP are placed in the center of the field of piriform gland spigots ( PI ).
The Zodariidae HNS are diagnosed by several characters not found in Penestominae (i.e. absence of serrula, lateral implantation of tarsal claw teeth, long anterior lateral spinnerets; see Jocqué 1991). Inclusion of Penestominae within the entirely ecribellate Zodariidae HNS would radically change and complicate the diagnosis of this expanded family concept. For these reasons, Miller et al. (2010) promoted Penestominae to family rank.