Photo Discussion
Category: Friendly Praise Archive

Tex

	" Tex " A wild immature male Texas Brown tarantula (Aphonopelma hentzi) showing pedipalps with cymbia, chelicerae and fangs. The Texas Brown is one of the most docile species of tarantula. Although being irritated he still is not exposing his fangs like they do in the attack mode. Copperas Cove, Texas 2 August 2009 Jim Baines

Pedipalps of spiders have the same segmentation as the legs, but the tarsus is undivided, and the pretarsus has no lateral claws. Male spiders bear enlarged palpal organs at the tip of their pedipalps, the terminal segments being elaborated into devices termed cymbia for the transfer of sperm to the sperm receptacles of the female. The palpal organs are species-specific and thus vital for taxonomy when identifying male spiders. This feature is unique to spiders. In this youngster you can see that the cymbia is not fully grown. Mature males appear to be wearing small boxing gloves on their pedipalps, a sure sign of sexual maturity.

Think of the pedipalps as hands.

Chelicerae are pointed appendages which are used to grasp food, and are found in place of the chewing mandibles most other arthropods have. Additionally, some chelicerae, such as those found in spiders, are hollow and contain (or are connected to) venom glands, and are used to inject venom into prey or a (perceived) threat. Except for a few small families of spiders, all spiders have venom that is injected into their prey through openings in the tips of their fangs when a spider bites something. The glands that produce this venom are located in the two segments of the chelicerae, and, in most spiders, extend beyond the chelicerae and into the cephalothorax.

Think of the chelicerae as being jaws that tear and crush prey.

The fang, the organic functional equivalent to a hypodermic needle is what penetrates the skin, fur, or exoskeleton of the spider's target--spider mouthparts are primarily intended for envenoming a spider's prey in most species, typically insects and other small arthropods; not for biting humans. The basal portion includes all or part of the spider's venom glands, which can be squeezed under voluntary control by the spider to force venom out of the glands and into the wound.[1] When a spider bites, the two parts of the chelicerae come together like a folding knife, and when making a threat display or actually preparing to bite, the spider will open the angle of the fangs with the basal portion of chelicerae and also open the angle of the basal portion with the cephalothorax. In the tarantulas and other and other Mygalomorphae, the horizontal separation of the tips of the fangs does not change much, but in the other spiders the tips of the fangs move apart from each other as well as elevating. Even the tips of the fangs of the rather large spider shown above are quite sharp, and the spider's body is well adapted to driving the fangs into flesh. Some spider bites, such as those of the Sydney funnel-web spider, are reported to have penetrated toe nails and soft leather shoes.

Think of the fangs as something that could make you curse violently.

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August 02, 2009

Dominick

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August 02, 2009

Happy Shooting
Jack

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August 02, 2009

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August 02, 2009

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August 03, 2009

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August 03, 2009