ARANEUS DIADEMATUS SPIDER
EUROPEAN GARDEN CROSS SPIDER

EUROPEAN GARDEN SPIDER

The spider species Araneus diadematus is commonly called the European garden spider, diadem spider, orangie, cross spider and crowned orb weaver. It is sometimes called the pumpkin spider, although this name is also used for a different species, Araneus marmoreus. It is an orb-weaver spider found in Europe and North America.

A. diadematus has a holarctic distribution, found throughout Europe and across North America, from southern Canada to Mexico, and from British Columbia to Newfoundland.

Araneus diadematus lives in grasslands and requires some form of moisture. The environment must provide plenty of attachment sites for the scaffolding of the web and there must be sufficient vertical open space for the orb web.

Individual spiders colourings can range from extremely light yellow to very dark grey, but all A. diadematus have mottled white markings across the dorsal abdomen, with four or more segments forming a cross. The markings are formed in cells filled with guanine, which is a byproduct of protein metabolism.

Adult females range in length from 6.5 to 20 mm, while males range from 5.5 to 13 mm. Occasionally, the female will eat the male directly after mating.

The legs of orb-weaver spiders are specialized for spinning orb webs. The webs are built by the larger females who hang head down in the center of the web or remain hidden in nearby foliage, with one claw hooked to a signal line connected to the main orb waiting for a disturbance to signal the arrival of prey. Prey is then quickly bitten and wrapped in silk before being stored for later consumption. The initial bite serves to paralyze the prey and minimize the danger of the spider herself being stung or bitten, and the enzymes thus injected serve to begin liquefaction of the prey's internal structures.

Alongside the use of the web to capture other prey, the spiders are also cannibals and prey on each other. However, this only happens before, during or after sexual activity. They attack based on their size, sexual experience and hunger levels.

This species rebuilds its web everyday to enhance the possibility of capturing prey. The protein composition of spider silk is unusual. Amino acids with short side-chains make up 50 to 60% of the total protein. Before building a new web, a spider eats its old web, conserving silk proteins. The web of Araneus diadematus usually has 25 to 30 radial threads forming regular angles of 12 to 15 degrees. Webs of young individuals often have many more radii than those of adults.

A. diadematus is a reclusive creature and only bites humans if cornered or otherwise provoked. It responds to a disturbance by vibrating rapidly in its web until it becomes a blur, a reaction that is assumed to confuse potential predators.