part of
preceded by
NF stage 39
NF stage 40
Nieuwkoop and Faber stage 40, corresponding to an embryo of age 2 days, 18 hr at 22-24 Celsius and having the following external morphological criteria: Mouth broken through. Length of gills about twice their breadth, posterior one sometimes also showing a branch. Outlines of proctodeum and tail myotomes forming angles of 90 degrees. Beginning of blood circulation in gills. Length: 6.3 - 6.8 mm.
XAO:1000052
xenopus_developmental_stage
late tailbud stage
NF stage