Santa Cruz Island Reserve, California-Arachnid

Spiders (order Araneae) are air-breathing arthropods that have eight legs and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every habitat with the exception of air and sea colonization. As of 2008, at least 43,678 spider species, and 109 families have been... less ↑

The Agelenidae are a large family of spiders in the suborder Araneomorphae. Well-known examples include the common "grass spiders" of the genus Agelenopsis. Nearly all Agelenidae are harmless to humans, but the bite of the "hobo spider" (Tegenaria agrestis) may be medically significant and there is evidence that it might cause necrotic lesions. The matter however remains subject to debate. The most widely accepted common name for members of the family is "Funnel weaver". less ↑

Theridiidae is a large family of spiders, also known as the tangle-web spiders, cobweb spiders and comb-footed spiders. The diverse family includes over 2200 species in over 100 genera) of three-dimensional space-web-builders found throughout the world. Theridiid spiders are entelegyne (have a genital plate in the female) araneomorph ecribellate (use sticky capture silk instead of woolly silk) spiders that often build tangle space webs and have a comb of serrated bristles (setae) on the tarsus of... less ↑

The crevice weaver spiders (super-family Filistatoidea, family Filistatidae) contain primitive cribellate spiders. They are haplogyne weavers of funnel or tube webs. The family contains 17 genera and more than hundred described species worldwide. One of the most abundant members of this family in the Americas is the Southern house spider (Kukulcania hibernalis). Named after the fierce Meso-American god Kukulkan, the females are large (up to nearly 20 mm) dark-colored spiders and males are light brown, smaller (about... less ↑

The Amaurobiidae are three-clawed cribellate or ecribellate spiders found in most parts of the world and difficult to distinguish from related spiders in other families, especially Agelenidae, Desidae and Amphinectidae. Their intra- and interfamilial relationships are contentious. In Spider Families of the World, 2007, they were represented by 69 genera and about 640 species in 5 subfamilies. less ↑

Phidippus is a genus in the family Salticidae (jumping spiders). Some of the largest jumping spiders inhabit this genus, and many species are characterized by their brilliant, iridescent green chelicerae. Phidippus is distributed almost exclusively in North America, with the exception of two exported species (Phidippus audax and Phidippus regius). As of 2004, there are 60 valid described species in the genus. Species previously described in Phidippus which are found in India and Bangladesh do not... less ↑

The spider family Oonopidae, commonly known as goblin spiders, includes over 2000 species in about 88 genera worldwide. The type genus of the family is Oonops Keyserling, 1835. They are generally tiny (1-3 mm) haplogyne araneomorph spiders. Some have hardened plates (scuta) on their abdomens. Oonopids usually have six eyes, the anterior median eyes having been lost. However, four-eyed (Opopaea viamao), two-eyed (e.g. Coxapopha, Diblemma) and even completely eyeless species (e.g. Cousinea, the cave-dwelling Blanioonops) are also... less ↑

The tube-dwelling spiders (family Segestriidae) consist of two large and widespread genera (Segestria and Ariadna) and one monotypic genus (Gippsicola from Australia). The family is easily recognized because its members have six eyes (most spiders have eight) arranged in a semicircle and have the first three pairs of legs arranged forward (most spiders have only the first two pairs so arranged.) The leg structure appears to be an adaptation for living in silken tubes, which unlike... less ↑

Lutica is a genus of zodariid spiders that occurs only in North America on both the mainland California coast and the Channel Islands. Lutica abalonea is known from the coast west of Oxnard, California, Lutica clementea is known from San Clemente Island, Lutica maculata is known from Santa Rosa Island, and Lutica nicolasia is known from San Nicolas Island. It is believed that there is another species found on San Miguel Island, though it has not... less ↑

Lynx spider is the common name for any member of the family Oxyopidae. Most species make little use of webs, instead spending their lives as hunting spiders on plants. Many species frequent flowers in particular, ambushing pollinators, much as crab spiders do. They tend to tolerate members of their own species more than most spiders do, and at least one species has been identified as exhibiting social behaviour. less ↑