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[YOUTUBE]vib9gfSkxfU[/YOUTUBE]
Virtually every spider you see has venom. Most spiders possess unimpressive venom that produces no real effect on human tissues. This is not to say they don't have venom... it is just more of an insecticide than anything else. However, there *are* some spiders that utterly lack venom.
The spider family Uloboridae is the only araneomorph (so called "true spiders") that completely lacks venom and even venom glands. There is one very primitive spider of the mesothelae branch that also lacks venom and glands, but it is a much close relation to trapdoors and the weirdo spiders. Uloboridae are known as hackled orbweavers because of the special kind of silk they they use to catch bugs in their orb webs.
The hackled part of the family name comes from a special organ the spider can choose to drag silk across as it is making it. The cribellum is a rough, comb type of organ that the spider can use to make "fuzzy" web. The fuzz is actually many many little frills and gyres of stressed and torn silk... and can actually be more "sticky" than the glue type webs most people are more commmon with.
In my video i also show another classic part of Ulo webs, the stabilimentum. Those are the areas of heavier webbing, often in a sort of zig zag pattern. The Ulo almost always seem to make their stabilimenta out of cribbelate webbing.
Stabilimentum and cribellate webbing can be found in many other families, and so in and of themselves are not good diagnostic features for Uloboridae. However, a cribbelate orb web with stabilimentum definitely is indicative of the family!
[This video uploaded from a 37MB WMV file]
Virtually every spider you see has venom. Most spiders possess unimpressive venom that produces no real effect on human tissues. This is not to say they don't have venom... it is just more of an insecticide than anything else. However, there *are* some spiders that utterly lack venom.
The spider family Uloboridae is the only araneomorph (so called "true spiders") that completely lacks venom and even venom glands. There is one very primitive spider of the mesothelae branch that also lacks venom and glands, but it is a much close relation to trapdoors and the weirdo spiders. Uloboridae are known as hackled orbweavers because of the special kind of silk they they use to catch bugs in their orb webs.
The hackled part of the family name comes from a special organ the spider can choose to drag silk across as it is making it. The cribellum is a rough, comb type of organ that the spider can use to make "fuzzy" web. The fuzz is actually many many little frills and gyres of stressed and torn silk... and can actually be more "sticky" than the glue type webs most people are more commmon with.
In my video i also show another classic part of Ulo webs, the stabilimentum. Those are the areas of heavier webbing, often in a sort of zig zag pattern. The Ulo almost always seem to make their stabilimenta out of cribbelate webbing.
Stabilimentum and cribellate webbing can be found in many other families, and so in and of themselves are not good diagnostic features for Uloboridae. However, a cribbelate orb web with stabilimentum definitely is indicative of the family!
[This video uploaded from a 37MB WMV file]
