User:NZNaturePassion/sandbox

NZNaturePassion/sandbox
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Corinnidae
Genus:	Nyssus
Species:	N. coloripes
Binomial name
Nyssus coloripes (Walckenaer, 1805)
Synonyms
Supunna picta (L.Koch, 1873) Nyssus michaelseni (Simon, 1909) Nyssus auripes (Rainbow, 1916) Nyssus bicolor (Hogg, 1900) Nyssus pictus (L. Koch, 1873) Nyssus versicolor (Simon, 1896) Nyssus variepes (Rainbow, 1912)

Nyssus coloripes, commonly known as the spotted ground swift spider Australian ground spider and swift ground spider is a spider belonging to the family Corinnidae, the Corinnidae spiders are a family group known as the ant mimicking spiders. It is found throughout Australia, including the mainland of Austraila and Tasmania and New Zealand. They are known for being out during the day and at night and for their particularly unique way of running swiftly in open areas. This spider has been reclassified in 2015 from its originally known name of Supunna picta (Loch, 1873) to its first name of Nyssus coloripes, named and described by Walckenaer in 1805, it was also previously thought to be in the family of Clubionidae known as the sac spider family, but now belongs to the Corinnidae family.

Description

The swift ground spiders appear mostly black in colour along the body and the back two/three pairs of legs. The first and sometimes second pair of legs appear a yellow to orange colour. The body and legs will have white spots in a stripe pattern, the females have a rectangular band of the white marks made up of white hairs followed by two white spots, a chevron and a hammerhead shaped spot all on the top side of the spider making up the patterns, these patterns are never on the underside. The underside will have a well defined V shape and is of varying shades of brown colours. The markings are more prominent in the females compared to the males of the species. The eyes are all of similar size and shape and made up in rows. They are classed as a small to medium sized spider with a typical body length of 6-7 mm, with the adult females being the larger of the two. They have a very distinct appearance and one of the most individual spiders you would see in New Zealand. Even with its bright colours and patterns with red being known to be poisonous or dangerous, their bite is not toxic to humans and require little to no medical treatment. The swift ground spider gets it common name as it has an unusual way of moving around compared to other spiders, it moves very rapidly at times in an erratic fashion, not moving in a straight line and changing direction many times and will move back and worth sometimes stopping and starting in a way to evade capture from predators but also does a similar style when hunting. While moving like this it will hold up its front orange legs to mimic that of the feeler front legs of the hunting wasp. These wasps in the family Pompilidae that it mimics are found world wide but some species in Queensland, Australia look similar to Nyssus coloripes. When resting the spider will remain close to the substrate and have its legs extended, with the legs flexed slightly. It will come to this resting position after moving and will even rearrange its legs to be in the right place with rapid movement of the legs into position.

Distribution

Nyssus coloripes can be found throughout its native country of Australia including on Tasmania. It was introduced to New Zealand in 1943 and was first seen in Auckland but has now spread to all parts of New Zealand. They are believed to be introduced to New Zealand by travel on shipping containers. It is common to see the swift ground spider in open habitats, around suburban houses and gardens, liking areas of short grass cover, it can also be seen in open areas like roads, dry country areas like grasslands and riverbeds. In Australia it can be found in open eucalypt forests and on the fringes of rainforests and vines. They are known to be diurnal meaning it likes to be out during the day and at night, and why it is commonly seen around the home. This suits its style of hunting on the ground and in the open without the use of a web. Nyssus coloripes can be found out in the open on sunny days hunting or can be found under rocks and at the bottom of shrubs for shelter.

Life cycle

Male Nyssus coloripes create a special web called a sperm web to transfer sperm from the testes to their palps for later breeding and courtship. These are usually a triangular sheet in style hung in the males web, when the transfer takes place it is called sperm induction. Some males to make their chances better at breeding will stay and live in the same web of sub-adult females waiting for the female to mature, then will mate with the female, this also increases the females chance of a long time reproducing being mated as soon as she is ready. While being researched it was found that females will only mate once with any male and will then store sperm for creating eggs later. If the female has already mated before and another male tries mating, she will not mate with him and even sometimes charge at the male and/or at times eat the male. The male when courting a potential female to mate will drum with his legs and palps usually just the first pair of legs but sometimes with the second pair as well, the male drums with these legs often flexed onto the female, the web or substrate nearby. It has been documented that males performed the courtships with females after touching the web or lines of silk from the female, this suggests that their could be pheromones in the silk associated with mating as well. The male can also be observed creating silk, doing abdominal bobbing up and down and jerky style walking during the courtship, the male will approach and retreat from the female usually head on a few times before mating. To mate the male will mount the female in the opposite direction to where she is facing and lean either to the left or right to insert his palp and give a convulsion at the time of insertion. The mating only lasts a few seconds and afterwards the male and female move away from each other. Once mated the females build an egg sac that is described as flat and papery, for which they will leave after creating and not look after till they hatch. This process of creating the egg sac by the females and the different parts of the egg sac can take hours. The egg sacs are oval in shape and 7-9mm long and 2-3mm of thickness. While making the egg sac the female will move and turn the egg sac so that the layers of silk thread go in different directions over the egg sac. The egg sac is made up of many layers of silk with the egg mass in the middle and is attached to the substrate slightly under rocks and covered in a silk mix with debris matter like dirt and leftover prey found by the female. Once the spiderlings are ready to hatch, they escape the egg sac by one or two curved slits in the egg sac lining.

Interactions

Nyssus coloripes is known for its varied hunting styles of open ground hunting, using their own web for hunting and also for invading other spiders webs and depends on it's speed to catch prey. In the wild the swift ground spider will eat other spiders quite often caught in that spiders own web and Phalangium opilio a species of harvestmen on the ground. It's competitors for Phalangium opilio are other species of spiders like the nursery web spiders, crab spiders and jumping spiders and also competition from the Pterostichus melanarius a species of beetle. It will eat insects in the wild of varying species. During a research study of Nyssus coloripes it was kept in a laboratory and fed a diet of fruit flies, houseflies, ants and salticid spiders, but it was found that it did not eat the ants. The spiders and houseflies are similar size to the swift ground spider and the fruit flies were smaller. When observed hunting the spider attacks it prey with rapid movement towards it, in a quick surprise style of attack, it will move onto the prey and hold it using its chelicerae, using its front legs to scoop and hold for the chelicerae or when needed will use more or even all its legs to hold the prey. It will sometimes catch more than one prey at a time and feed on them as a single food bundle. When catching prey from its own web the swift ground spider will respond as soon as the prey touches its web as the web is not always strong enough to hold its prey, if the prey does get out of the web the spider will make chase and run down and catch the prey returning to its web tunnel to feed on the prey. When hunting using other spiders webs it will enter and walk on the silk of the other web or around the outside of it, when on the web it will hunt and eat the owner of the web or other prey caught in the web. The downside of hunting in other spiders webs is that the swift ground spider can accidently become the prey for the other spider as well. The swift ground spider can become caught in sticky silk type webs and will have to bite its way free and then spend time grooming its legs to get the residue off. If the spider whos web the swift spider approaches while stuck in their web the swift spider will freeze with the hope that the resident spider will leave it alone or it becomes the prey.

Further Information

Sometimes thought to not build webs of their own. Once researched in a laboratory setting and in the wild the Nyssus coloripes males, females and juveniles were all seen to build webs of their own. These webs were not as grand and complex as other species of spiders but were often small in size and not made of sticky silk and was positioned under rocks or other objects for shelter. They consisted of 3-dimensional arrays of web silk with thicker silk tunnels near the bottom where the spider would sit on the substrate and moult, eat prey and deposit eggs in them. A few lines of silk would cover the substrate but mostly it was open to the ground. The size of the web can vary from 50 to 100mm across and can be made up with more than one tunnel in them. The web was not thought to be created to catch prey but more as extra sensors for the swift ground spider, this is common of most web building spiders but the swift ground spiders act uniquely in it's way of running after and catching prey that happened upon its web.

References

Category:Spiders of Oceania Category:Spiders described in 1873