Katipo

Red Katipo, females

The Red Katipo ( Latrodectus Katipo ), often just called Katipo, is a web spider from the family of cobweb spiders. It belongs to the New Zealand species of the genus of the Real widows.

Description

The females of the species reach a body length of about 8 millimeters and the leg span is about 32 millimeters. They have a spherical abdomen the size of a pea. The legs are slender and black in young animals and turn brown later. The abdomen has a red-orange, square strip of white- orange or red border that extends to the spinnerets. The underside is black with a red spot showing the usual rights widows Sanduhrzeichnung, but this drawing may be absent in some females. The species belongs to the widow spider species whose basic color is matte rather than glossy black.

The males are much smaller and reach about one- sixth the size of the females. They also differ in their coloration. Males and juveniles have a brown color with a predominantly white belly, with irregular red-orange, diamond -shaped drawings.

Occurrence and Habitat

The Katipo lives endemic to New Zealand. In the North Island it is widespread along the west coast between Wellington and the North Cape. Mostly it occurs also on the east coast. On the Great Barrier Island it is still relatively common. In the South Island their range extends from north to south along the east coast to Dunedin, on the west coast to Greymouth. This southern limit of distribution is related to the lower average temperatures in the south of New Zealand. The eggs of the spider require a temperature of over 17 ° C in order to develop.

In general, the Katipo lives in the dunes near the beaches. Your irregular cobweb she grows plants of Desmoschoenus spiralis and on the ordinary beach grass (Ammophila arenaria ). But also to driftwood to build the animals networks or in waste, such as empty cans and bottles. The network has the form of a colored hammock and is white or yellow.

Way of life

The species feeds on insects of all kinds of amphibians too will not despise.

Between August and September is mating season, the male looking for a female. Does it have a female found, so it goes to the net, causing it to vibrate. The female responded quite aggressively at first and chased the male. The courtship is the fact that the male jumps again and pulls at the net. If the female is submissive, it leaves the male to the network and can be hung upside down, so that the male can insert the palps into the genital opening of the female, and can transmit the seeds. In contrast, as many other species, the males do not eat the females after mating. The female produces 5-6 egg sacs. The eggs are round and just as big as a mustard seed. They carry a transparent violet. Mismatches with the closely related redback spider (L. hasselti ) are known.

The Katipo has no noteworthy natural enemies. It has been observed only a ichneumon, which feeds on the eggs of Katipo.

Endangering

Unlike its close relative White Widow ( Latrodectus pallidus ) in North Africa and the Middle East, or also closely related Southern Black Widow ( Latrodectus mactans ) in the U.S., the Red Katipo is only rarely encountered in their area of ​​distribution. It is assumed that only 50 populations in the North Island and eight populations exist in the South Island of New Zealand. The spider is classified in the Red List as "vulnerable". The decline of the populations has to do with increased use of the coast by the people, for the habitats of Katipo are rarely more than a few hundred meters from the beach. This habitat is threatened by:

• Recreational activities such as the use of beach buggies and off-road vehicles
• Development of cities and settlements
• Expansion of agricultural and forestry area
• Cultivation of non-native plants that change the entire biocenosis

In addition, the Katipo of a competitor, the entrained wrong Katipo ( Steatoda capensis ) seems to be displaced. The Wrong Katipo preferably have similar habitats, but has less specialized demands on their habitat. It provides two times a year for posterity, in the spring and early summer, the local Katipo only once per year.

The type even threatened with extinction ever. So it was protected by the Wildlife Act 1953, 2010.

Bite accidents and toxicity

Like all types widow, as well as the Red Katipo is not aggressive. You only bites when alarmed or attacked, the first Katipo goes into a defensive posture, good use of this nothing, so they bombarded with threads, it is still irritated, they can bite. Females, who guard their egg sac, bite each fault immediately. The main components of poison are neurotoxin and alpha - latrotoxin. The bite triggers goosebumps and local pain. In addition, you get a headache, fever, hypertension and tremor. This continues for 24 hours. However, a speedy visit to the doctor can help. In exceptional cases, it can cause coma, pulmonary edema, respiratory arrest, and local skin infections.

Taxonomy and systematics

Latrodectus Katipo was described in 1871 by L. Powell.

The Katipo was often confused with the also popular in New Zealand Steatoda capensis. This led to the name wrong Katipo (English: False Katipo ) for these belonging to the fat spiders Art A relative of Katipo, which also belongs to the genuine widows, is from Australia entrained Redback Spider ( Latrodectus hasselti ).

Black Katipo

The Black Katipo, which was established in 1890 by AT Urquhart as a subspecies of Latrodectus Katipo atritus and 1995 as a separate species Latrodectus atritus, is a color variant of the Katipo. Today it is no longer recognized as a separate species. Besides the coloring, the black color morph no distinguishing features to the Red Katipo. Experiments in the laboratory have shown that there is no crossing barriers. Pairs consisting of Black and Red Katipo, could together produce offspring. Also, there is no molecular evidence of a genetic splitting of the two groups. The color version is created, depending on the geographical latitude and temperature.