Less common than Crested Larks and easily mistaken for the latter, Thekla Larks are normally found in less "managed" habitats. Diagnostic features that distinguish them from Crested Larks are a straighter, shorter bill, a more proportioned crest with all feathers being of equal length and a hint of an eye stripe, particularly behind the eye itself. The rump is meant to be rufous-tinged and there is meant to be a lack of any rufous beneath the wing, both opposite to Crested Larks, but both of these two diagnostics I have never found to be useful in the field.
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