Where to Find and Catch Lombre
From Pokemon Go Wiki
Lombre are found and captured in Nest and Habitat locations.
Nests
Lombre Nests are locations that consistently spawn Lombre.
Habitats
Lombre Habitats are spawn locations where Lombre is likely to be encountered, but not guaranteed the way a Nest is.
Additional Tips and Information
Best Nests
If you know a really good nest or any of the nests above is really good, list them here: