How to distinguish a fertilized tarantula egg from an unfertilized one

[Theraphosid Research Team]

We are often asked how to tell if the tarantula eggs are fertilized. In the case of unfertilized tarantula eggs (here using the example of a Pamphobeteus sp. "mascara") it is easy to see that no development of body structures can be seen inside the egg. Only the yolk clods ( = DS: Fig. 1 & 3) and the perivitelline fluid ( = PV: Fig. 2) with the fine-grained yolk are clearly visible. Why the eggs or their cleavage cells did not develop remains unsolved. In comparison, a developed and fertilized egg from Sericopelma sp. "El Copé" shortly before the praelarva hatched (Fig. 4). The spider's segmented body is clearly visible. What is striking here are the cuticle hooks or so-called "egg teeth" (Fig. 5, green arrows) dorsal to the coxae of the palps (red arrows), which tear the chorionic cyst when the embryo hatches. According to Foelix, "hatching enzymes" from the pedipalp glands may also prepare this process. With the simultaneous first moult when hatching from the egg, these cuticle hooks disappear or are not formed again, as can be seen in Fig. 6.

LITERATURE:
Foelix, R. (2015): Biologie der Spinnen. Edition Chimaira, Frankfurt a.M.

by Volker von Wirth from Theraphosid Reserach Team

 

[BoyFromLA]

Lovely, lovely indeed.

 

[spideyspinneret78]

Fascinating. Thanks for sharing!

 

[Tarantuland]

This is really helpful, thank you. What does the PE stand for in figure 2? is that the perivitelline fluid? I have an egg sac thats slowly developing and I believe there to be many unfertilized eggs so I will put some up under my microscope

 

[Theraphosid Research Team]

This is really helpful, thank you. What does the PE stand for in figure 2? is that the perivitelline fluid? I have an egg sac thats slowly developing and I believe there to be many unfertilized eggs so I will put some up under my microscope

You are right. PE = perivitelline fluid. PV is a mistake. Sorry!

 

[CJJon]

Thank you for these posts! World-class stuff...

The board is much richer for it!

 

[jc55]

Fascinating information and pictures.Thanks for sharing.

 

[coolnweird]

I can't tell you how excited I am to have more reliable, scientifically based info on here! Thanks a bunch!!