Al-yes, they are venomous. ALMOST all spiders are venomous. There are a very, very few that are not. Almost without exception, all spiders are venomous, commonly enough either the venom is impotent against humans, or the fangs of the spider are too small or delicate to deliver it through human skin.
The uloboridae (which wrap their prey in silk, then secrete digestive enzymes over it whilst its still alive), a group of miniscule predatory spiders, the liphiistidae are non-venomous, these are medium to large spiders with mygalomorph type fang morphology, and are not venomous, relying on their size and physical power plus large chelicera to physically overpower their prey, quite possibly the most primitive group of all spiders, forming a sister lineage to the araneomorphs and mygalomorphs (spiders which have fangs operating in a sideways-oriented pincer-like manner, and those which have downward-pointing, stabbing fangs, such as Loxosceles, Phoneutria and Latrodectus (the recluse spiders, brazilian wandering spiders and widows) as well as common orb-weaver spiders are araneomorphs, whilst the likes of mouse spiders, funnelwebs and wishbone spiders are mygalomorphs. The sea-spiders are another matter altogether, having stabbing stylets, like a mosquito or true bug (E.g assassin bugs) whilst originally thought to be at least a member of the order Chelicerata (spiders, scorpions, harvestmen, mites, pseudoscorpions, whipscorpions, camel 'spiders' (Solifugids), they may in fact not be, and be a sister group to all other arthropods, a relic of the Ediacaran biota, having similarities to the likes of Anomalocaris, not found within any other living creature. Peculiar creatures with a much reduced body plan, so much so, that they keep parts of their digestive tracts within their legs, of all places)
The mesothelids are spiders, of a kind, but basal, very primitive creatures, with a feature found on no other spider lineage-a segmented abdomen, covered with segmented plates, suggesting that they are a sister group to the spiders and scorpions in evolutionary terms, having diverged when both spiders and scorpions were separating as distinct groups during the evolution of both.
And there is a single known species of vegetarian spider, believe it or not. Whilst occasionally it does eat animal life, in the form of ant larvae, it feeds almost exclusively on the protein-rich nutrient packages certain acacia species provide for symbiotic ant colonies, which themselves protect the acacia trees by attacking and killing invading insect species which would otherwise attack the acacias. The trees in turn, provide little orange-yellow packets of protein specifically intended as nutrients for the ant larvae as motivation, and the ants have evolved to depend upon these. The spider feeds on these packages too, being agile enough to evade the vicious ants, as its one of the jumping spiders. Thus far, it is the only known vegetarian spider.
There are one, maybe two other orders of spider similar to the Uloborids, in that they are tiny (a few mm at most) and lack venom, but otherwise all true spiders, bar these, the Uloboridae and the Mesothelids (Liphiistidae) are venomous. Being harmful to humans is another kettle of fish entirely.
As for todays good happening at chateaux de Lestat, my old man just bought me a small fridge so I can keep my volatile solvents in it, got it cheap for just £30. Strictly speaking, he wants it to keep maggots in for his fishing, but said I can use it, and told me before I even had chance to observe the fact, that most likely, I'll be the one who by far and away gets the most use out of it. Just the sort of thing I need to keep solvents that have a propensity to escape through containers, and are difficult to contain. Things like diethyl, diisopropyl ether, THF, methylene chloride, chloroform, carbon disulfide, that kind of thing. As it happened, I'd been debating whether to spend today's pay portion allocated to lab supplies on a fridge, for just that purpose (minus the maggots) or a new heating mantle w/ magnetic stirring plus some new three necked flasks. Could do with some more of those, plus now I don't need to buy a fridge (this even has a freezer, so I can run a dedicated coolant line through it circulating something like an antifreeze/alcohol mixture, or a freon-type refrigerant to run through my condenser lines plumbed through the freezer portion. Really chuffed about that. Means I can buy myself the new fritted vacuum filter funnel I wanted too. Oh boy, that'll free up quite a bit of money, for me to spend all on goodies for the lab
Just plotting and scheming as to exactly what I want. I've got several hundred quid to do an update for this two week period
I can't wait to go shopping
First on the list I think is some potassium or sodium bromide, preferably NaBr, since the atomic weight of sodium is less than that of potassium and its a convenient storage medium (plus sometimes reagent in its own right) for the otherwise very difficult to contain bromine, which must hold one of the championship titles for most bastardly reagents of all to store, it seeps through pretty much everything and anything bar glass given the slightest of chances. So I prefer to store it as a bromide salt, needing only to pass chlorine gas through a solution of it, which replaces the bromide anion with chloride, precipitating out bromine, which is insoluble in water, bar to a very small extent (enough to color water, producing 'bromine water', which itself is useful as a titration reagent for the presence of alkenes, one can determine whether a product has an alkene double bond, to which bromine adds, forming an alkyl bromide, a dilute solution of Br2 in water decolorizes in the presence of alkenes, due to this reaction, and it can be, if the weight of the original compound is known, used to determine how many double bonds there are, or if they are present at all.
Presumably it also adds to alkynes, although I've never actually looked that up. Other than that, I'd like very much to improve my ultra-microscale setup (for working at the scale of ~5ml or less, smallest flasks I currently have are 10ml. Could do with a good quality vacuum manifold and pressure regulator rather than relying solely on pinch-clamps, plus some more clamp stands. Although for that, all I'll do is visit a scrap metal merchant and bag a few dirt cheap blocks of iron or steel, drill holes in them and tap them on the lathe, plus pare down some stainless, preferably chrome plated steel bar on one end and cut a screw thread to match. That kind of thing, being designed specifically to be weighty and secure stuff has to be heavy and as such would be murder on the shipping. And why pay for what you can likely pick up the starting materials for a fiver or less in scrap steel and cut the threads yourself in less than a half hours work.
Definitely really pleased about that fridge w/freezer. Nice, very nice (unless you happen to be a maggot. Then again, can't be as bad as having a hook stuck up your arse then a fish sucking your guts out
)