I should know this but I don't..

14pokies

Arachnoprince
Joined
Oct 25, 2014
Messages
1,735
At what stage( instar) do slings produce the waxy coating that retains moisture inside of there exoskeleton?
 

Marijan2

Arachnobaron
Joined
Oct 21, 2012
Messages
505
http://jcs.biologists.org/content/joces/s3-95/31/371.full.pdf

Some key points from the article:
-In the unhardened cuticle such as is found in the arthrodial membrane of juvenile specimens, the epicuticle is undifferentiated;
-The outer membrane and the outlying zone of the basal lipoprotein layer give a positive Fehling test on prolonged treatment. The region giving this reaction is also positive to the murexide test.
-Cuticle in different growth-stages was used for the application of the test, and it was of interest to note that in the earlier stages of growth before the cuticle was fully hardened the murexide test was positive in the epicuticle, while in the fairly hardened cuticle the reaction appeared more intense in the exocuticle
-What little is known of the epicuticle of other arachnids (Browning, 1942; Lafon, 1943a, 19436; Cloudsley-Thompson, 1950; Sewell, 1951) suggests that in them the epicuticle may not conform to a common pattern. It appears probable that two distinct types based on the mode of hardening may occur in this class, one approximating to the condition met with in insects, as exemplified by the ticks (Lees, 1946, 1947), and the other characterized by the occurrence of —S—S— bonding as seen in the scorpion (Krishnan, 1953) and Limulus (Lafon, 1943a). It is questionable how far the differences between the two types can be explained as due solely to the occurrence or absence of —S—S— bonding


I am not completely sure myself, but from what i deducted from this document is that slings and adults have same composition of epicuticle. additionally, use of waxy layer and outer epicuticle to protect from moisture loss is mainly after moulting, and as they harden the exocuticle layer becomes prominent and additionally helps with water retaining. Also, as they grow bigger and older, exocuticle takes more and more job of taking care of water retain from epicuticle. Meaning right as slings emerge from eggs, their waxy layer is at their best

I really hope someone who is much more knowlegeable in this area comes and sheds light how accurate this is, and if i even interpret it right
 

viper69

ArachnoGod
Old Timer
Joined
Dec 8, 2006
Messages
17,851
http://jcs.biologists.org/content/joces/s3-95/31/371.full.pdf

Some key points from the article:
-In the unhardened cuticle such as is found in the arthrodial membrane of juvenile specimens, the epicuticle is undifferentiated;
-The outer membrane and the outlying zone of the basal lipoprotein layer give a positive Fehling test on prolonged treatment. The region giving this reaction is also positive to the murexide test.
-Cuticle in different growth-stages was used for the application of the test, and it was of interest to note that in the earlier stages of growth before the cuticle was fully hardened the murexide test was positive in the epicuticle, while in the fairly hardened cuticle the reaction appeared more intense in the exocuticle
-What little is known of the epicuticle of other arachnids (Browning, 1942; Lafon, 1943a, 19436; Cloudsley-Thompson, 1950; Sewell, 1951) suggests that in them the epicuticle may not conform to a common pattern. It appears probable that two distinct types based on the mode of hardening may occur in this class, one approximating to the condition met with in insects, as exemplified by the ticks (Lees, 1946, 1947), and the other characterized by the occurrence of —S—S— bonding as seen in the scorpion (Krishnan, 1953) and Limulus (Lafon, 1943a). It is questionable how far the differences between the two types can be explained as due solely to the occurrence or absence of —S—S— bonding


I am not completely sure myself, but from what i deducted from this document is that slings and adults have same composition of epicuticle. additionally, use of waxy layer and outer epicuticle to protect from moisture loss is mainly after moulting, and as they harden the exocuticle layer becomes prominent and additionally helps with water retaining. Also, as they grow bigger and older, exocuticle takes more and more job of taking care of water retain from epicuticle. Meaning right as slings emerge from eggs, their waxy layer is at their best

I really hope someone who is much more knowlegeable in this area comes and sheds light how accurate this is, and if i even interpret it right
Interesting paper, cool they used X-ray diffraction on a scorp.

How much of this paper applies to their cousin the tarantula?
 

14pokies

Arachnoprince
Joined
Oct 25, 2014
Messages
1,735
when they have adult colors.
So untill they are adults they are like sponges? Wouldn't this mean that in fact slings can drown..5

I don't believe this to be true so your statement has to have a more in depth explanation.. Just prodding you for knowledge lol..
 
Last edited:

bryverine

Arachnoangel
Old Timer
Joined
Apr 18, 2012
Messages
890
So untill they are adults they are like spunges? Wouldn't this mean that in fact slings can drown..

I don't believe this to be true so your statement has to have a more in depth explanation.. Just prodding you for knowledge lol..
It just means they can't maintain/hold water in their abdomen as easily. Though I still need to read that sciencey paper above...

It doesn't change their density or water tension on their feet.
 
Top