- Joined
- Mar 25, 2015
- Messages
- 2,217
One point that has annoyed me for a while is that you can't find reliable data for average tarantula sizes. Most sites give maximum sizes and even those are usually wildly inaccurate and in many cases I've the strong impression people just copy from other pages or pull random numbers out of their behind. Especially the size of larger species usually gets overestimated. While rare exceptions may actually reach those maximum sizes you'll find on the web, the average spider in your care will probably not. So, I'd love a thread about the very simple question: how large does a specific species of tarantula actually get on average.
First we need some rules for measuring:
- leg span
- actually measured, not estimated, either from molt or stretched out on the enclosure side for arboreals
- mostly stretched out, but not forcefully so.
- the spider should be an older adult that is not expected to gain significantly in size anymore. Of course spiders can grow for all their lives, but once they reach a certain size/age further growth is minimal.
- the thread should NOT be about bragging about your oh so very large spiders, but it should give realistic data about what to expect
Myself, I own older adults of a number of species that are advertised as getting very large (no Theraphosa, though), but not a single one of my spiders has reached 8". Here are some numbers, sorted by size:
7.5"
- Acanthoscurria geniculata. Actually I have two, raised from sling and now 8 and 9 years old, and neither has reached 8".
- Lasiodora klugi. She looks bigger, because that's one massive spider, but when actually measured she's still below 8".
- Poecilotheria rufilata.
7"
- Lasiodora difficilis. The slightly smaller, fluffier cousin of the klugi
- Phormictopus sp. green femur
- Xenesthis immanis
- Pamphobeteus nigricolor. I've bought this as nigricolor but I'm in Europe and I'm not exactly sure that this is the same species that gets sold as nigricolor in America.
- Psalmopoeus cambridgei. In my experience this is the largest of the NW arboreals by quite a margin.
6.5"
- Phormictopus cautus violet
- Sericopelma generalum
- Pamphobeteus insignis
- Poecilotheria regalis
6"
- Grammostola pulchripes
- Megaphobema mesomelas. This spider is massive, with a huge body and short legs and therefore looks much bigger than the leg span indicates.
- Poecilotheria subfusca "highland" or whatever the proper name is right now.
- Lampropelma nigerrimum
- Psalmopoeus irminia
- Phormictopus auratus (bought as platus)
(- Chilobrachys Kaeng Krachan. This one may actually still grow a bit)
5.5"
- Nhandu chromatus. Don't believe anyone that tells you Nhandus get big. I've two of those from different breeders and both only reached this size. And I fed them properly, too, ad libitum as slings and juveniles.
- Tapinauchenius polybotes, formerly sold as sanctivincenti. This is actually the largest Tapi, not gigas (now Pseudoclamoris gigas). If you can get your hands on this species I very highly recommend it, one of my favorite arboreals, chill and nearly always out.
- Pterinochilus murinus
- Megaphobema robustum
5"
- Pseudoclamoris gigas. I've seen some discussion about this species specifically, but mine is pretty exactly 5".
- Caribena versicolor
- Pterinochilus chordatus
- Tlitocatl albopilosus - now I've read everywhere they get bigger, so this may be a runt, but mine really is this small.
- Brachypelma hamorii
- Brachypelma auratum. All others of my Brachys I do not consider to be fully grown yet - Brachys grow excruciatingly slow.
- Nhandu carapoensis
- Phormingochilus sp. rufus - highly recommended species, very outgoing and makes spectacular webs.
I'm running out of time for today, but I'd love if people would post their own numbers here.
First we need some rules for measuring:
- leg span
- actually measured, not estimated, either from molt or stretched out on the enclosure side for arboreals
- mostly stretched out, but not forcefully so.
- the spider should be an older adult that is not expected to gain significantly in size anymore. Of course spiders can grow for all their lives, but once they reach a certain size/age further growth is minimal.
- the thread should NOT be about bragging about your oh so very large spiders, but it should give realistic data about what to expect
Myself, I own older adults of a number of species that are advertised as getting very large (no Theraphosa, though), but not a single one of my spiders has reached 8". Here are some numbers, sorted by size:
7.5"
- Acanthoscurria geniculata. Actually I have two, raised from sling and now 8 and 9 years old, and neither has reached 8".
- Lasiodora klugi. She looks bigger, because that's one massive spider, but when actually measured she's still below 8".
- Poecilotheria rufilata.
7"
- Lasiodora difficilis. The slightly smaller, fluffier cousin of the klugi
- Phormictopus sp. green femur
- Xenesthis immanis
- Pamphobeteus nigricolor. I've bought this as nigricolor but I'm in Europe and I'm not exactly sure that this is the same species that gets sold as nigricolor in America.
- Psalmopoeus cambridgei. In my experience this is the largest of the NW arboreals by quite a margin.
6.5"
- Phormictopus cautus violet
- Sericopelma generalum
- Pamphobeteus insignis
- Poecilotheria regalis
6"
- Grammostola pulchripes
- Megaphobema mesomelas. This spider is massive, with a huge body and short legs and therefore looks much bigger than the leg span indicates.
- Poecilotheria subfusca "highland" or whatever the proper name is right now.
- Lampropelma nigerrimum
- Psalmopoeus irminia
- Phormictopus auratus (bought as platus)
(- Chilobrachys Kaeng Krachan. This one may actually still grow a bit)
5.5"
- Nhandu chromatus. Don't believe anyone that tells you Nhandus get big. I've two of those from different breeders and both only reached this size. And I fed them properly, too, ad libitum as slings and juveniles.
- Tapinauchenius polybotes, formerly sold as sanctivincenti. This is actually the largest Tapi, not gigas (now Pseudoclamoris gigas). If you can get your hands on this species I very highly recommend it, one of my favorite arboreals, chill and nearly always out.
- Pterinochilus murinus
- Megaphobema robustum
5"
- Pseudoclamoris gigas. I've seen some discussion about this species specifically, but mine is pretty exactly 5".
- Caribena versicolor
- Pterinochilus chordatus
- Tlitocatl albopilosus - now I've read everywhere they get bigger, so this may be a runt, but mine really is this small.
- Brachypelma hamorii
- Brachypelma auratum. All others of my Brachys I do not consider to be fully grown yet - Brachys grow excruciatingly slow.
- Nhandu carapoensis
- Phormingochilus sp. rufus - highly recommended species, very outgoing and makes spectacular webs.
I'm running out of time for today, but I'd love if people would post their own numbers here.
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