Theraphosids

 Tarantulas, Baboon spiders, Bird-eating spiders Mygalomorphs.
 
Background: Tarantulas, Baboon spiders, Bird-eating spiders, and Mygalomorphs are all names used for this large group of spiders found across the world, the name being dependent on where they are found. Baboon spiders are generally African, Tarantulas are generally American, Bird-eating spiders are generally South American. Trap door spiders, funnel web spiders and purse web spider are also in this group

They are in a group (Sub-order) separated from the true spiders (Araneomorphs) such as your common house spider or Garden spider, by the presents of two paired lung books (breathing holes under the abdomen) and fangs that point downwards (which is why all Tarantula's must rear up to bite). True spiders only have one pair of lung books and side-ways working fangs.

Origin: World wide apart (even two species of Purse web spider found in Europe)

Habitat: Varied - from deserts to tropical Rainforests.

Natural food: All other insects

Temperature range: 22-28C depending on species

Culture: Most species can be kept in containers with a minimum of about 2-4x the leg span of the spider. This does not sound much but most species live in tunnels and rarely leave them so are quite happy as long as food is available to them and temperature and humidity requirements are met. Larger display tanks are OK but often much of the space is wasted and is for the benefit of the owner rather than the spider.

For arboreal species such as Avicularia sp height is more important than floor space.

Some species (many African species for example) tolerate quite dry conditions (65 - 750% humidity) but some moisture is often appreciated. Other species (many South American species such as the Avicularia) prefer very wet conditions (90-95% humidity). Most will be relatively happy somewhere in between. If the container is large enough a humidity gradient is a good way of working out your pets ideal humidity.

Similarly, ideal temperatures vary between species but 25-28C is generally OK.

Feeding: Virtually anything live will be taken as long as the size is not too large. Most people use crickets or locusts which can be purchased from many reptile shops and pet shops. Live insects can be collected from the garden if necessary but it is not generally recommended as it would not be known if they are contaminated with insecticides or parasites. A good food size is about half the size of the spider. However some aggressive species or a good feeder will often tackle a cricket slightly larger than itself but this should be watched as large prey could damage the spider if not eaten and any food not eaten after a day should be removed.  Care should be taken especially if the spider is coming up to a moult.

Moulting: Periodically spiders (and all other invertebrates) moult (grow a new skin and discard the old - see the photo gallery). This is a critical time for all spiders and many spiders are lost at this. The signs of an imminent moult are a darkening of the abdomen skin and a refusal of food. This may only occur a day or so before the moult in spiderlings or a few weeks in adults. Ideally the spider should be left alone during this period and for a similar time after the moult whilst the new skin hardens and dries. Any live food should be removed if not eaten straight away during this time and definitely not offered during the moult itself.

Sexing: Sexing of Tarantulas is slightly complicated especially to the new comer. Mature males can be identified after the final moult by the appearance of palpal bulbs on the front two "legs" (palps) and often by the appearance of Mating hooks on the second pair of legs (actually the first pair of proper legs). Before this moult, males are almost identical to females although some people claim to be able to identify them by appearance. They can be reliably identified by looking at the inside of a fresh moult but this requires some experience of the species, a magnifying glass or microscope and of course a fairly fresh moult. In general be very careful if some one tries to sell you a sexed spider unless you know they are reliable.

Breeding: Breeding of spiders only really requires placing a mature male and female spider together. Male spiders are only mature after their last moult when palps develop. These organs appear on the first pair of "legs" and are used for the transfer of sperm. In most species Tibial Hooks are also present and these are used to help push the female backwards to allow the male access to her sexual opening (epigastric farrow). Males do not moult again once these are present and will die a few months to a year after this although they generally are only of use for mating for a few months after moulting. Females continue to moult once mature. If the female moults after a mating before laying eggs, the sperm is lost and no eggsac will be produced.

Eggsacs are best left with the female although they can be artificiaaly incubated. Sometimes eggsacs are eaten, Often this is due to it not being fertile but some females will also eat fertile ones if disturbed or for no apparent reason.

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