Name: NF stage 1
XAO ID: 1000001
Definition: "Nieuwkoop and Faber stage 1, corresponding to an embryo of age 0 hr and having the following external morphological criteria: One cell stage, shortly after fertilization. Pigmentation darker ventrally than dorsally. Length: 1.4 - 1.5 mm."
|Preceded By: mature egg stage||Succeeded By: NF stage 2-|