Coua cristata maxima—species or subspecies, adult or juvenile, extant or extinct, aberrant or hybrid?

Coua cristata maxima, known by nothing more than a unique specimen taken in south-east Madagascar in 1948, was distinguished by its greater size than other subspecies of Crested Coua C. cristata (of which pyropyga, sometimes accorded species rank, is the largest) and by its shorter crest, bluer upperparts, wings and tail, fully cinnamon-tawny underparts and mid-sized white tail tips. A separate assessment of the holotype published in 1997 made various refinements to this diagnosis, and our own examination found the facial configuration seemingly inconsistent with that of pyropyga, showing a weaker superciliary line and possibly a reduced area of bare skin around the eye, although these features may, like the short crest, simply be indications of immaturity. Even if they are, however, maxima appears too distinct to retain subspecific rank: it seems more likely to be either a full species or, as first intimated in 1997, a hybrid. Four of the six Coua species around the type locality cannot be possible parents, but seven features of the holotype are consistent with a Blue Coua C. caerulea × C. cristata pairing. Molecular investigation is urgently needed to determine whether maxima is a valid species. If it is, it will either be highly threatened or extinct; little-known hinterland forest from Manafiafy (35 km north-east of Taolagnaro) north at least to Manantenina has been identified for survey.