Garden Orb Weavers - Page 1
Here's some photos of those common Garden spiders from the Orb Weaving family. My apologies if there are some Araneus on pages where they don't belong but they are very hard to classify. Try this page for a species guide:
http://bugguide.net/node/view/1972/bgpage
Orb weavers (Araneidae) are often brightly coloured with rounded abdomens, some with peculiarly angled humps or spines. However, there is considerable variation in size, colour and shape in this group. They are easily recognized because of their beautiful, large, round webs, on which they rest, head downward, waiting for prey. The webs consist of a number of radiating threads crossed by two spirals. The inner spiral begins in the centre, winds outward, and is made of smooth threads like the radiating threads. It covers only the central 1/3 of the web. The outer spiral begins at the edges and winds inward. It is made of more elastic, sticky threads, coated with a liquid substance. One of the largest and most commonly encountered members of this group is Argiope aurantia, the yellow garden spider and we have photos of them on their own page. Garden Orb Weavers are NOT dangerous (but can bite as can most spiders) and rid your garden of many unwanted insects. They only live for one season and die off as Winter approaches, leaving their egg sacs behind to hatch out next Spring.
All photos are copyright to their owners and may not be reproduced without permission.
There are many varieties of orb weaving spiders and I have only included some of them on these pages.
The species below are:
Page 1: Garden Orb Weavers (Unspecified species), Triangulate Orb Weaver, Shamrock Orb Weaver, Marbled Orb Weaver, Giant Lichen Orb Weaver, Cat Face Orb Weavers, Araneus Alsine-like/Aranaeus Iviei/Araneus Nordmanni.
Page 2: Araneus Cingulatas, Green Orb Weavers, Araneus Diadematus, Star Bellied Orb Weavers, Arabesque Orbweaver, Tropical Orb Weavers.
Because of the large number of species, I have only included a few of the best photos. Click the name to go to that section.
Garden Orb Weavers
Triangulate Orb Weavers [top]
This species is sometimes called the "arrowhead spider." The genus name, Verrucosa, means "warty" and refers to the small wartlike bumps on the abdomen. This is the only species of Verrucosa in the United States. They are members of the garden orb weaver family (araneus). On females, the carapace (head) is glossy chocolate brown and small compared to the similarly colored, triangular abdomen. A triangle of colour almost completely covers the top of the abdomen, with the bottom angle pointing away from the spider's head; this triangle resembles a white, pink, or yellow flattened drop of shiny glue. This species rests centered in its web head-up instead of head-down, and the legs are often folded up against the body. Males are smaller and don't look very much like the females, as they lack the characteristic triangle on the abdomen. Males are rarely seen unless they are in a female's web either courting or mating with her. As a general rule, spiderlings hatch from eggs in spring and spend the growing season eating, maturing, mating, and laying eggs. Females are capable of creating webs; males are not. Females continue creating egg cases as long as the weather holds out. As temperatures cool in fall, their metabolism slows, and they generally die when it freezes. Egg cases overwinter, and spiderlings hatch in spring.
Shamrock Orb Weavers [top]
Shamrock or Pumpkin Spiders as they are called in different places scientific name is Araneus trifolium. A. trifolium is a spider which builds an orb-web and is classified in a group of spiders called orb-weaver spider. Colour is a characteristic that may help to identify a spider. A. trifolium is orange (though it may show up in a yellowish green or purplish form). Its large, bulbous abdomen is similar to a pumpkin. Measuring a spider's length also helps in its identification. A. trifolium is large, compared to other spiders. Size is an important way of distinguishing one spider from another. The abdomen also contains the stomach or crop. In the fall the abdomen and the entire spider grows quickly. The high vegetation the spider prefers produces an abundance of insect food; and in the fall there is a growth spurt when food is most plentiful. This sudden increase in size may be cause for the spider's "sudden" appearance. In fact, the spiders have been present all-year, but were much smaller and simply less noticeable. The spider tends to show up around Halloween - and that is how it got its common name "Pumpkin Spider."
Marbled Orb Weavers [top]
Commonly called the marbled spider, Araneus marmoreus belongs to one of several genera of orb or orb weaver spiders that frequently are found as adults on or around houses and other buildings from late summer to fall. Adult female marbled spiders are 9-18mm long; some other orb spiders are smaller and some larger. Most species live one year, but some survive longer. Orb spiders are not aggressive and, like the vast majority of spiders, are not dangerous to people. Bites are rare and usually are no worse than a bee or wasp sting. As they age in Fall, many marbled orb weavers change colour from bright yellow to orange, reminiscent of a pumpkin's colour and so are also called pumpkin spiders because of their colour and the fact that it is often around Halloween!!
Giant Lichen Orb Weavers [top]
Araneus bicentenarius, the giant lichen orbweaver, is a species of orb weaver in the family Araneidae. It is found in the USA and Canada. Ihis species gets its common name from the greenish colour of its abdomen which resembles lichen or moss. Like most orb weavers, they are harmless to humans.
Cat Face Orb Weavers [top]
Araneus gemmoides, commonly known as the Jewel Spider (a name shared with Austracantha minax) and Cat-faced Spider (a name shared with Araneus gemma), is a common outdoor orb-weaver spider found in the USA and Canada. They are considered harmless and have low-toxicity venom. A. gemmoides are useful natural predators for insects. A. gemmoides make their webs near lights, closed spaces, and on the sides of buildings. They can also be found under wood, overhangs, or guarded places such as animal burrows. They come in varying colours but are easily identified by the two horn shaped growths on their relatively large abdomen. Their colour changes from summer to winter. The female will die within days of laying a single egg sac with hundreds of eggs. Egg sacs can overwinter, and the emerging spiderlings will eat their brothers and sisters. The babies ride strands of silk in warm air currents, able to transport them to locations miles away.
Araneus Alsine-like/Araneus Iviei/ Araneus Nordmanni [top]
The strawberry spider or orange wheelweaving spider (Araneus alsine) is a species of the orb-weaving spider (Araneidae) family. Araneus alsine can reach a body length of 6.5–8.5 millimetres (0.26–0.33 in) in males, of 12–14.9 millimetres (0.47–0.59 in) in females. These spiders have a large, almost globular or slightly elliptical shaped opisthosoma, ranging from beige to reddish-orange, with many white-and-yellow spots spread over the surface and sometimes forming the sign of a cross. Sternum, chelicerae and legs are reddish brown. Legs show darker annulations in males. As one of its common names suggests, A. alsine appears somewhat like a strawberry. Below the first 2 photos are of Araneus Alsin-like and the next 3 are of Araneus Iviei and the second 5 pretty green ones with the yellow pattern are Araneus Nordmanni. Araneus nordmanni is a species of orb weaver in the family of spiders known as Araneidae. It is found in North America, Europe, Caucasus, a range from Russia to Kazakhstan, Korea, and Japan. I haven't had too many photos of these spiders sent in over the years.
