The duration of each development stage depends on the temperature!
This information is from:
Bulltin Biologique de la France et de la Belgique (TOME CXIII 1979 No.1) LE COMPORTEMENT ALIMENTAIRE ET LA DIVISION DU TRAVAIL CHEZ LA FOURMI LASIUS NIGER.
Author: Alain Lenoir.
Alain Lenoir says:
Workers at 25°C
- egg to larvae 15 days
- larva to pupae 10 days
- pupae to immature adult 15 days
- six weeks from egg to ant.
Goetsch says:
Workers
- egg to larvae max. 27 days
- larva to pupae max. 15 days
- pupae to immature adult max. 92 days
(here Alain Lenoir says that the larvae can vegetate much longer then 15 days)