Very new - question about measurements

[TracyRee]

Hello. I am super new to tarantulas. Just got my first yesterday!

Something I haven't been able to figure out for sure by googling... when someone is referring to a tarantula as being a certain measurement, are they referring to it's body size or legspan? (Say an online seller)

Thanks! Lots to learn and loving it.

 

[PanzoN88]

Diagonal Legspan

 

[boina]

In America: always diagonal leg span.
In Europe: varies, often body length, though diagonal leg span is becoming more popular. Only the Germans insist on body lenght.

 

[Nightstalker47]

Measuring the body length is just ridiculous, it will vary greatly depending on where the tarantula is in its molt cycle.

DLS is better in every way.

 

[boina]

Measuring the body length is just ridiculous, it will vary greatly depending on where the tarantula is in its molt cycle.

DLS is better in every way.

I'm not getting into that discussion - I mean, I love discussions in general, but not this one. But: German keepers will tell you that leg span just varies too much depending on how streched out the tarantula is.

I want to state explicitely that I don't care either way - I just use what everyone else is using.

 

[Nightstalker47]

I'm not getting into that discussion - I mean, I love discussions in general, but not this one.

Kind of forcing my hand here with your reply though.

But: German keepers will tell you that leg span just varies too much depending on how streched out the tarantula is.

They dont understand the term properly then...DLS only applies to fully stretched out tarantulas. Its always best to do it with molts, but if you can get a ventral measurement that works too.

 

[Theneil]

USUALLY diagonal leg span (tip of leg one on one side to tip of leg four on opposite side when stretched out)

Some also measure legspan on only one side ex: left leg one to left leg 2

body length (i believe) is from the front of the chelicera to the tip of the abdomen. (i don't think spinnerettes count)

Best thing to do is ask the seller befor you buy if you want to know. And possibly better than asking an exact size is jut see if you can get a picture with some object (like a coin) that makes easy reference.

Personally, i don't know why we don't all use length of the carapace to size them. That does NOT ever change during a molt cycle... (half for real and half trolling with this last comment...)

 

[The Grym Reaper]

US & UK generally use DLS

Mainland Europe generally use body length although some breeders don't even measure, they just list the moult number/instar (written as 5i or 5fh or L5 or something similar) to troll everyone like we're supposed to know how big [insert species here] is after 5 moults.

 

[Theneil]

US & UK generally use DLS

Mainland Europe generally use body length although some breeders don't even measure, they just list the moult number/instar (written as 5i or 5fh or L5 or something similar) to troll everyone like we're supposed to know how big [insert species here] is after 5 moults.

You don't have the size for every instar of every species memorized yet? You must be slacking on the research.

 

[The Grym Reaper]

You don't have the size for every instar of every species memorized yet? You must be slacking on the research.

I know, I'm a terrible keeper

 

[lazarus]

They dont understand the term properly then...DLS only applies to fully stretched out tarantulas. Its always best to do it with molts, but if you can get a ventral measurement that works too.

That's exactly the problem with DLS, you can't reliably measure it on a live spider, you can just measure the exoskeleton and even those only before they've fully dried. So for all spiders that you see for sale the DLS is pretty much just a guesstimate.

Measuring the body length is just ridiculous, it will vary greatly depending on where the tarantula is in its molt cycle.
DLS is better in every way.

The variation is at most 1cm for an adult T, still a lot more accurate that the precision of guesstimating the DLS

I've also read a few species description and I don't remember seeing DLS being specified anywhere in those papers, but the body length is always there and also the size of each pair of legs.

 

[Nightstalker47]

That's exactly the problem with DLS, you can't reliably measure it on a live spider, you can just measure the exoskeleton and even those only before they've fully dried.

Yes you can, you just need to wait for the right opportunity...as I mentioned earlier, ventral measurements are very accurate. Based on this logic, how does one reliably measure the BL of a living tarantula...seems to be just as difficult if not more. I know my fingers arent going anywhere the carapace of my spiders for a measurement.

So for all spiders that you see for sale the DLS is pretty much just a guesstimate.

I have always bought tarantulas based on their DLS, and have never been surprised with something being under sized or vice versa. Depends on the vendors though, perhaps the Germans were measuring them wrong(scrunched up) as was mentioned earlier. The very definition implies the maximum leg span, thats why we measure diagonally.

The consensus on these terms is clearly not the same everywhere though, so I can see where the confusion is coming from.

 

[lazarus]

Yes you can, you just need to wait for the right opportunity...

Yes, once every blue moon a tarantula will sit with it's legs fully stretched

Based on this logic, how does one reliably measure the BL of a living tarantula...seems to be just as difficult if not more.

If it's sitting against the glass you just put the ruler on the glass and measure, if it's on the substrate you put the ruler a few cm above the T and using projection points you get the body length.

I have always bought tarantulas based on their DLS, and have never been surprised with something being under sized or vice versa. Depends on the vendors though, perhaps the Germans were measuring them wrong(scrunched up) as was mentioned earlier.

Well I've just recently bought a "4cm DLS" unsexed C. darlingi. It molted about 3 weeks later and lo and behold he's now a mature male, measuring the exoskeleton he was actually close to 7 cm.

 

[The Grym Reaper]

Well I've just recently bought a "4cm DLS" unsexed C. darlingi. It molted about 3 weeks later and lo and behold he's now a mature male, measuring the exoskeleton he was actually close to 7 cm.

All this proves is that the seller stitched you up.

 

[Jayk]

In America: always diagonal leg span.
In Europe: varies, often body length, though diagonal leg span is becoming more popular. Only the Germans insist on body lenght.

What have you got against Germany