Endangered beauties: micro-CT cranial osteology, molecular genetics and external morphology reveal three new species of chameleons in the Calumma boettgeri complex (Squamata: Chamaeleonidae)

Based on recent discoveries and an integrative study including external morphology, osteology and molecular genetics, we continue to revise the Madagascar-endemic chameleons of the Calumma boettgeri complex (within the Calumma nasutum species group). We describe three new species of these small-sized, occipital-lobed chameleons. Calumma uetzi sp. nov. is a species from the Sorata and Marojejy massifs (northern Madagascar), with a spectacular display coloration in males, clearly notched occipital lobes, and females with a dorsal crest. Calumma lefona sp. nov. is described based on a male specimen from Tsaratanana (northern Madagascar), with widely notched occipital lobes, a long and pointed rostral appendage, a dorsal crest, and a frontoparietal fenestra in the skull roof. This last character also occurs in six other Calumma species, and its presence and width are correlated with the elevational distribution of the species. Calumma juliae sp. nov. is known only from a small, isolated forest fragment near Moramanga in eastern Madagascar, and only females have been found so far. It is a relatively large member of the C. nasutum group, with a distinct dorsal crest and numerous infralabial scales. Two of the new species are known exclusively from their type localities, and we recommend protection of the habitats of all three as soon as possible.