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Family Theridiosomatidae - Ray Spiders

Ray spider - Theridiosoma gemmosum - female egg, egg sack, pupa? - Theridiosoma gemmosum Spider egg case? - Theridiosoma gemmosum hanging egg sac - Theridiosoma gemmosum spider and prey - Theridiosoma Ray spider? - Theridiosoma gemmosum Spider - Theridiosoma gemmosum - male Spider - Theridiosoma gemmosum - male
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Chelicerata (Chelicerates)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Entelegynae)
Family Theridiosomatidae (Ray Spiders)
This family has only two species in North America, both in genus Theridiosoma.(1)
The Theridiosoma genus was once included in the orb weaver family (Araneidae) due to the general appearance of the species, and since they weave a modified orb web. However, they are distinguished from the Araneidae by the relatively large space between the anterior row of eyes and the anterior edge of the carapace (referred to as the width or height of clypeus). Theridiosomatidae spiders have the height of clypeus higher than the distance between the anterior and posterior median eyes.
Works Cited
1.Spiders of North America: An Identification Manual
D. Ubick, P. Paquin, P.E. Cushing and V. Roth (eds). 2005. American Arachnological Society.