Lynx Spider

Lynx spider is the common name for any member of the family Oxyopidae. Most species make little use of webs, instead spending their lives as hunting spiders on plants. Many species frequent flowers in particular, ambushing pollinators, much as crab spiders do. They tend to tolerate members of their own species more than most spiders do, and at least least one species has been identified as exhibiting social behaviour.

Description and habits

There are several genera of Oxyopidae and they differ in their habits and adaptations. Most of them have large spiny bristles on their legs and in many species the bristles form almost a basket-like structure that may assist in confining the prey that they grasp, and protect the spider from its struggles. Most Oxyopes and Hamataliwa species are small to medium in size; they tend to be drab ambush hunters; depending to some extent on the season, some occupy flowers, ambushing pollinating insects. In this they resemble the crab spiders (Thomisidae) in behaviour. Others crouch in wait, camouflaged on plant stalks or bark. Peucetia species on the other hand, commonly are larger. They are rangy and their camouflage is vivid green, adapted to hunting or hiding among foliage.
Lynx spiders, in spite of being largely ambush hunters, are very speedy runners and leapers, alert and with good vision. Except when defending egg purses, many tend to flee rapidly when approached by predators or large creatures such as humans. They tend not to be very aggressive towards other members of their own species, and sometimes meet casually in small groups. Possibly as an extreme example, at least one member of the genus Tapinillus is remarkable as being one of the few social spiders, living in colonies with communal feeding, cooperative brood care, and generational overlap.
Oxyopidae in general rely on keen eyesight in stalking, chasing, or ambushing prey, and also in avoiding enemies. As with many other families of spiders, the arrangement of their eyes is typical of the family and is an important aid in identifying them as members of the family. Six of the eight eyes of Oxyopid spiders are arranged in a hexagon-like pattern, more or less on a prominent hump on the front upper corner of the prosoma. The other two eyes are smaller, less conspicuous, and generally are situated in front of and below the other six. The basal parts of the chelicerae of most species are large, vertical and parallel, which combine with the bluff front end, a "high forehead" to the prosoma, to give most species a peculiar "flat-faced" appearance.
Genera common in the United States include Oxyopes — the common lynx spiders — and Peucetia — the green lynx spiders.
Some members of the genus Oxyopes are abundant enough to be important in agricultural systems as biological control agents. This is especially true of the striped lynx spider (Oxyopes salticus). Their net value in agriculture has been disputed however, on the grounds of their predation of pollinators.
Peucetia viridans also is unusual among spiders in that females defending their egg purses will spray or "spit" venom at intruders, including humans.

Classification :

 Kingdom : Animalia
Phyllum : Arthropoda
Class : Arachnida
Oder : Arachneae
Superfamily : Lycosoidea
Family : Oxypoidea

Golden Orb Weaver

                                                     Golden silk orb-weaver

The golden silk orb-weavers (genus Nephila) are a genus of araneomorph spiders noted for the impressive webs they weave. Nephila consists of numerous individual species found around the world. They are also commonly called golden orb-weavers, giant wood spiders, or banana spiders. In North America, the golden silk orb-weavers (see also Nephila clavipes) are sometimes referred to as writing spiders due to occasional zigzag patterns (stabilimenta) built into their webs, though these occur much more frequently in the webs of Argiope, such as the St Andrew's Cross spider.
The species N. jurassica, which lived about 164 million years ago, had a leg span of some 15 cm (6 in), and is the largest known fossilized spider.
The genus name Nephila is derived from Ancient Greek, meaning "fond of spinning", from the words (nen) = to spin (related to nema νήμα "thread") + φίλος (philos) = "love".

Appearance and distribution

Nephila spiders vary from reddish to greenish yellow in color with distinctive whiteness on the cephalothorax and the beginning of the abdomen. Like many species of the superfamily Araneoidea, they have striped legs specialized for weaving (where their tips point inward, rather than outward as is the case with many wandering spiders). Their contrast of dark brown/black and green/yellow allows warning and repelling of potential predators to whom their venom might be of little danger.
Golden orb-weavers reach sizes of 4.8–5.1 cm (1.5–2 in) in females, not including legspan, with males being usually 2/3 smaller (less than 2.5 cm, 1 in). The largest specimen ever recorded was a 6.9 cm (2.7 in) female N. plumipes (which is now debated to have been a new yet undocumented subspecies) from Queensland, that was able to catch and feed on a small-sized finch. In 2012 a large individual was photographed killing and consuming a half-metre-long brown tree snake in Freshwater, Queensland. Species from Taiwan have been known to reach over 5 in (130 mm), legspan included, in mountainous country.
Golden silk orb-weavers are widespread in warmer regions throughout the world, with species in Australia, Asia, Africa (including Madagascar), and the Americas. One species, N. clavipes, occurs in the United States of America, where it ranges throughout the coastal southeast and inland, from North Carolina to Texas.
Nephila spiders are the oldest surviving genus of spiders, with a fossilized specimen known from 165 million years ago.

Web spinning

The name of the golden silk orb-weavers refers to the color of the spider silk, not the color of the spider itself.
Yellow threads of their web shine like gold in sunlight. Xanthurenic acid, two quinones and an unknown fourth compound contribute to the yellow color. Experimental evidence suggests that the silk's color may serve a dual purpose: sunlit webs ensnare bees that are attracted to the bright yellow strands, whereas in shady spots the yellow blends in with background foliage to act as a camouflage. The spider is able to adjust pigment intensity relative to background light levels and color; the range of spectral reflectance is specifically adapted to insect vision.
The webs of most Nephila spiders are complex, with a fine-meshed orb suspended in a maze of non-sticky barrier webs. As with many weavers of sticky spirals, the orb is renewed regularly if not daily, apparently because the stickiness of the orb declines with age. When weather is good (and no rain has damaged the orb web), subadult and adult Nephila often rebuild only a portion of the web. The spider will remove and consume the portion to be replaced, build new radial elements, then spin the new spirals. This partial orb renewal is distinct from other orb-weaving spiders that usually replace the entire orb web. In 2011 it was discovered that the web of Nephila antipodiana contains ant-repellent chemicals to protect the web.
Typically, the golden orb-weaver first weaves a non-sticky spiral with space for 2-20 more spirals in between (the density of sticky spiral strands decreases with increasing spider size). When she has completed the coarse weaving, she returns and fills in the gaps. Whereas most orb-weaving spiders remove the non-sticky spiral when spinning the sticky spiral, Nephila leave it. This produces a "manuscript paper" effect when the orb is seen in the sun: groups of sticky spirals reflecting light with "gaps" where the non-sticky spiral does not reflect the light.
The circular-orb portion of a mature N. clavipes web can be more than 1 meter across, with support strands extending perhaps many more feet away. In relation to the ground, the webs of adults may be woven anywhere from eye-level upwards high into the tree canopy. The orb web is usually truncated by a top horizontal support strand, giving it an incomplete look.
Adjacent to one face of the main orb there may be a rather extensive and haphazard-looking network of guard-strands suspended a few inches distant across a free-space. This network is often decorated with a lumpy string or two of plant detritus and insect carcasses clumped with silk. This "barrier web" may function as a kind of early-warning system for incoming prey or against spider-hunting predators, or as a shield against windblown leaves; it may also be remnants of the owner's previous web. At least one reference explains the suspended debris-chain as a cue for birds to avoid blundering into and destroying the web.
Stabilimenta among N. clavipes are sometimes seen in the webs of immatures nearing molt, hence the names "molting webs" or "skeleton webs" (webs with radial strands but no spiral elements).

Prey-capturing mechanisms

The Australian golden silk orb-weaver (Nephila edulis) has been observed on windy, rainy days dismantling the lower part of its web to allow strong wind to flow through a large opening in the web without breaking it. Golden Orb Weavers are known to occasionally eat prey as big as small birds and even snakes

Spiderlings 

 Young spiders do not generally build yellow-colored silk, and the young Nephila themselves can be easily mistaken for young Orchard Spiders (Leucauge) in general color and shape (both species sport silver stripes or patches on their abdomens, described in some references as a form of heat control). The best distinction between Leucauge and Nephila juveniles is web structure: Leucauge tends to build a horizontal orb that is a perfect circle, whereas Nephila build vertical, elliptical orbs that are incomplete (missing the portion of the orb over the hub, the center where the spider sits). Nephila seem to prefer more open habitat such as second-growth scrub or forest edges. Fences or building overhangs often do just as nicely.
In addition, young spiders demonstrate vibrational motion when approached by a predator. They will oscillate at approximately 40 Hz when the web is plucked—thought to be a response to a potential predator. If a predator persists in an attack, the spider will either run to a web-support strand and thus to nearby vegetation, bail out of the web on a silk line that remains connected to the web, or jump from the web after inducing oscillations in the web

Classification :

 Kingdom : Animalia

Phyllum : Arthropoda

Class : Arachnida

Order : Araneae

Family : Nephilidae

Genus : Nephila

Crab Spider

                                                      
Plot : 
               After a good macro tutorial, i went to field in search of good objects. I first took a walk in the field to check out which bush/trees/herbs present there. I saw many possibilities of good spiders. I got many clicks of different species. But this was something i was waiting for since long time. I had got crab spider's clicks earlier too, but bcz of shiny nature of this spider i was not able to get good clicks in earlier meetings.

                                                              Crab Spider
Crab spider is a common name applied loosely to many species of spiders, but most nearly consistently to members of the family Thomisidae. Among the Thomisidae it refers most often to the familiar species of "flower crab spiders", though not all members of the family are limited to ambush hunting in flowers.

Crab spider as a name in common use

Rationalisation for the name crab spider is generally subjective and anecdotal. It is commonly said to refer to a fancied resemblance to crabs, or to the way such spiders hold their two front pairs of legs, or their ability to scuttle sideways or backwards. Some spiders so called have bodies that are flattened and angular. At all events, the Thomisidae are the family most generally referred to as "crab spiders". However, some members of the Sparassidae are called giant crab spiders, Selenopidae are called wall crab spiders, and various members of the Sicariidae are sometimes called six-eyed crab spiders. Some unrelated Orb-weaver spider species such as Gasteracantha cancriformis also are commonly called "crab spiders."
Such names are of little biological significance, and in this article the emphasis is on the Thomisidae.

Crab spider biology

Thomisidae do not build webs to trap prey, though all of them produce silk for drop lines and sundry reproductive purposes; some are wandering hunters and the most widely known are ambush predators. Some species sit on or beside flowers or fruit, where they grab visiting insects. Individuals of some species, such as Misumena vatia, are able to change color over a period of some days, to match the flower on which they are sitting. Some species frequent promising positions among leaves or bark, where they await prey, and some of them will sit in the open, where they are startlingly good mimics of bird droppings. However, note that these members of the family Thomisidae are not to be confused with the spiders that generally are called bird dropping spiders, not all of which are close relatives of crab spiders.
Other species of crab spiders with flattened bodies, either hunt in the crevices of tree trunks or under loose bark, or shelter under such crevices by day, and come out at night to hunt. Members of the genus Xysticus hunt in the leaf litter on the ground. In each case, crab spiders use their powerful front legs to grab and hold onto prey while paralyzing it with a venomous bite.
The spider family Aphantochilidae was incorporated into the Thomisidae in the late 1980s. Aphantochilus species mimic Cephalotes ants, on which they prey.
The spiders of Thomisidae are not known to be harmful to humans. However, spiders of an unrelated genus, Sicarius, which are sometimes referred to as "crab spiders", or "six-eyed crab spiders", are close cousins to the recluse spiders, and are highly venomous, though human bites are rare.

Classification :

Kingdom : Animalia
Phyllum : Anthropoda
Class : Arachnida
Order : Araneae
Superfamily: Thomisoidea
Family: Thomisidae