Spider Facts: Orb Weaving Spiders (Araneidae)

Types of Spiders Orb Weavers: Araneidae Genus Araneus Genus Argiope (Writing Spiders) Cyrtophora (Tropical tent-web Spider) Genus Eriophora (Tropical Orbweaver) Genus Gasteracantha (Spinybacked Orbweaver) Genus Larinia (Striped Orbweaver) Genus Neoscona (Spotted Orbweaver) More Types of Spiders

Jumping spiders many be cute, and perhaps have a vegetarian leaning, however, when most people think spider, they think Araneidae.

Flat, round webs, and the spiders that build them, make the orb weaving spiders of the family Araneidae among the most easily recognized group of spiders in the world.

Common knowledge about Araneidae just about stops with those facts.

Stopping there would be a mistake. Knowing about genera and species diversity within the family may not make for interesting bedtime reading, except at Halloween, but it does make for some interesting spider facts.

A few of the more interesting facts are produced below, along with their sources.

All Araneidae do not spin webs. Spiders in the genus mastophora, commonly called bolas spiders, did not receive the Araneidae web spinning memo. (source: Bolas spider)

Recent research suggests that the Araneidae family dates back to the Jurassic Era (206-144 million years ago). It seems logical to suggest that species in the family adopted the adage, if it's not broke, don't fix it. They figured out how to survive using webs millions of years ago.

That same research suggests that around the world, Arachnologists and spider enthusiasts have documented 2847 Araneidae species, placed withing 167 genera. Taken together, the family "ranks third (out of 110) in terms of number of described spider species". The Araneus and Argiope links in the box represent two such genera. (source: Oldest true orb-weaving spider (Araneae: Araneidae).

Speaking of numbers, the The Journal of Arachnology recently published a key to The Genera of Arenid Orbweavers of the Americas saying, there are 65 genera and about 1,500 different species found from South America, north to Canada.

Finally, according to the book, The Orb-weaving Spiders of Canada and Alaska, the number of Araneidae genera and species decreases the further north one goes.

There are approximately 30 genera and 165 species of Araneidae north of Mexico, but only 19 genera and 62 species in Canada. The United States has over one hundred more Araneidae species than Canada.

Please click on any link in the box to learn more about specific Araneidae species.

© 2008 Patricia A. Michaels