The egg of Corduregastridae

A final renewal day is September 20, 2003.


Corduregastridae which inhabits Kinki area is one kind.

How to obtaining eggs : It tries to pierce a long valvula valvae, and lays eggs with Anotogaster sieboldii in the swamp and the inside of the sand of the little flow. The female which lays eggs is found. After that, the sand of the place to lay eggs is collected. The eggs are taken out from that sand.  An egg right after laying can't distinguish a color from the sand grain. But, an egg becomes orange color after one day. You will have an egg found.


1.  Anotogaster sieboldii (Selys)

Size: Right after laying; head diameter; 0.70mm, a short diameter 0.55mm. Just before hatching; head diameter 0.74mm, a short diameter; 0.58mm. Duration of egg : The shortest duration; 51days. Average duration; 55days.

Figure8-1: Left; After laying, the 7th day  Right; After laying, the 24th day

 As for the left photograph, a little sand grain sticks to the jelly-shaped material around the egg. Jelly-shaped material around the egg is removed in the right.

 

Figure8-2: Hatching