Missing/duplicate biome name

If you run sk89q's World Edit you can query /biomeslist. The command along with a page number lists all 62 biomes, but /biomelist 3 (page 3. Pages 1, 2, and 4 show no discrepancies) lists the "Mega Spruce Taiga" (numbers 160 and 161 per the Wiki) twice. One of then should be "Mega Spruce Taiga Hills" (missing). Without that biome I think it's probably not possible to earn the "Adventuring Time" achievement.
TIA
Lou
The only MC version I looked at was 1.7.10. There may be other problems I didn't test for.