Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada

Species Psilochorus rockefelleri

Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Chelicerata (Chelicerates)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Synspermiata)
Family Pholcidae (Cellar Spiders)
Genus Psilochorus
Species rockefelleri (Psilochorus rockefelleri)
Size
~2.5-3.0 mm total length(1).
Identification
"Specimens may be distinguished by: males spur short and wide, curving inward and pointed in dorsal view (Fig. 138), spur is located on the proximal half of the chelicerae and is equal to or less than half of the cheliceral length (Fig. 139), procursus tip squared off with a dorsal step (Fig. 142) epigynum with two prominent ridges on the MEP which are as wide as tall (Fig. 145), narrow PEP projection (Fig. 144)....This species was the most variable in the development of the genitalic features. The retrolateral tip of the bulb apophysis was found to occasionally curve ventrally making it difficult to see. Spurs of males were found which were: long and narrow, very thick and bulbous, represented as mere bumps, or were absent. Several were found with the spur on each chelicerae being of a different shape. Females varied in the development of the triangular bulge on the MEP. In some females the bulge would not be visible. No other species was this variable and the above mentioned diagnostics should be used cautiously. As indicated before, multiple specimens may be needed for a positive identification(1)".
Range
Arizona, New Mexico(1).