Австралиялық әдемі өрмекшілер туралы

Genus of spiders
the Australian genus and species of spider

Jewel spiders have a distinctive appearance that makes them relatively easy to identify. It is covered with small white hairs (setae). Its most distinctive feature are the three pairs of large "spines" projecting outwards. The first two pairs on the front are close to each other, forming a V shape as they point to the sides. They are short and roughly conical. The spines on the rear are longer and point backwards. There are wide spaces between them and the two front pairs. The spines are black or brownish black from above, but has a yellow orange to rusty red lower surfaces. The carapace is slightly rectangular, usually around long and wide Jewel spiders found later in autumn (from March to April) are also sometimes melanistic, being entirely dark brown to black in colouration. They are more common on the southern regions of the continent, from southern Queensland and New South Wales, through Victoria and Southern Australia, to Western Australia. Though they can be found in the Northern Territory, they are less common and their place is usually taken by species from the genus Gasteracantha instead.

Jewel spiders are cathemeral, remaining active both day and night. Females build vertically oriented orb webs about from the ground and in diameter. Nonetheless, the webs may sometimes be encountered damaged and reduced to only a few threads. The webs are more or less permanent, unlike many other orb weaver spiders which regularly destroy and rebuild their webs every day. Females do not make retreats near their webs. Instead they rest in the centre of the web with their head downwards. They can often be found living near each other in large overlapping aggregations of orb webs of usually thirty individuals. Aggregations were also observed to attract more males as well as protect the females from predators. However, the egg sacs in communal webs were attacked more often by parasitoids than the egg sacs laid by solitary females.

[[File:Austracantha minax egg sacs. jpg|thumb|Egg sacs attached to a grass stalk and a flower (Sydney, 1909) The egg sacs are around in length and can vary in shape from circular to pointed at both ends. They are reddish brown to golden brown in colour, though rarely they may also be bright yellow. They are made from closely woven silk. The spiderlings overwinter within the egg sacs until early spring. Females reach sexual maturity at around the middle of January, while males mature earlier in the middle of December.

Jewel spiders are considered harmless, When disturbed, they will try to escape by clambering upside down along their support threads to nearby surfaces (albeit slowly due to their short stubby legs). Failing that, they will drop to the ground. In Perth and the rest of Western Australia, the appearance of jewel spiders in large numbers in gardens (as well as the flowering of Nuytsia floribunda) is often associated with the coming of Christmas.