Taxonomic revision of fossil Psilodercidae and Ochyroceratidae spiders (Araneae: Synspermiata), with a new species of Priscaleclercera from Burmese amber

JÖRG WUNDERLICH; ABEL PÉREZ-GONZÁLEZ; IVAN L. F. MAGALHAES; DANIEL N. PROUD; ANDRÉS O. PORTA; MARTÍN JAVIER RAMÍREZ

Online

Simposio; 2020 AAS Virtual Summer Symposium; 2020

American Arachnological Society

Psilodercidae contains ~200 known extant species of small spiders that live in tropical rainforests and caves. The family is mainly restricted to the Oriental biogeographic realm. Interestingly, at least ten different fossil species have been described from inclusions in Late Cretaceous Burmese amber. This suggests the family has been diversifying in the region for ~100 million years. We revise the taxonomy of fossils of this family and its close relative, the Ochyroceratidae, basing on the re-examination of type specimens. We find that ten Cretaceous species described in the psilodercid genera Priscaleclercera and Aculeatosoma are valid, and present new illustrations of their type material. The genus Propterpsiloderces apparently does not belong to Psilodercidae, but rather to a stem lineage of one of the Scytodoidea families. Ochyroceratidae is represented by a single ochyroceratine genus from Miocene Dominican amber, Arachnolithulus. Finally, we present the description of a hitherto unknown species of Priscaleclercera from Burmese amber, bringing the total of congeners to ten. By studying its morphological features, we argue that Priscaleclercera is a crown Psilodercidae in the Althepus?Leclercera lineage. The high species diversity of Priscaleclercera indicates that Psilodercidae were already a diverse component of the Oriental tropical forests since the Cretaceous.