How long does it take for a salamander to regenerate a limb?
The length of time it takes a salamander to regenerate varies in several ways.
As a salamander gets older, its ability to regenerate decreases. But regeneration is still possible and old salamanders continue to regenerate missing or damaged tissues. In general, smaller larval salamanders regenerate faster than terrestrial salamanders. A juvenile axolotl can regenerate a limb in approximately 40-50 days, however terrestrial forms take much longer. For example, Young (1983) found that different terrestrial ambystomatid species show a great range of variation in regeneration rate: Ambystoma tigrinum regenerates a limb in 155-180 days; A. texanum in 215-250; A. maculatum in 255-300; and A. annulatum does so in 324-375 days. So, not only do age and body size influence regeneration, but different species also regenerate at different rates. It is also expected that individuals within species show variation in regeneration.
To learn more:
Young HE, Bailey CF, Dalley BK. 1983. Gross morphological analysis of limb regeneration in postmetamorphic adult Ambystoma. Anat Rec 206:295- 306.