|A male Tantilla tjiasmantoi Koch & Veneagas, 2016.|
Seasonally dry tropical forests have a distinct seasonality with several months of arid-like conditions when many plants lose their leaves. In South America, these forests are discontinuous and can occupy large areas such as the Caatinga in northeastern Brazil or small fragments as being found in inter-Andean valleys of Peru or Ecuador. The species compositions differ substantially from one seasonally dry forest to another. The Equatorial dry forest stretches from southern Ecuador to the northern part of Peru where it extends southward in two small stripes. One stripe continues along the west coast of the Andes, the other penetrates the valley of the Marañón River and its tributaries. Sixty-one species are currently recognized within the genus Tantilla. Twelve species occur in mainland South America, of which only two are found in Peru: T. capistrata and T. melanocephala. Most Tantilla have a uniformly colored or a longitudinally striped dorsal color pattern. Only T. shawi Taylor, from Mexico, T. semicincta from Colombia and Venezuela, and T. supracincta from Colombia, Costa Rica, Ecuador, Nicaragua, and Panama have a transverse-banded color pattern on the dorsal part of the body. Koch and Venegas (2016) describe a new Tantilla from the dry forest of the northern Peruvian Andes based on two specimens, which exhibit a conspicuous sexual dimorphism. Tantilla tjiasmantoi sp. nov. represents the third species of the genus in Peru and one with an unusual transverse-banded pattern. A detailed description of the skull morphology of the new species is given based on micro-computed tomography images. The habitat of this new species is seriously threatened due to human activity. Conservation efforts are urgently needed in the inter-Andean valley of the Maranon River.
Koch C, Venegas PJ. (2016) A large and unusually colored new snake species of the genus Tantilla (Squamata; Colubridae) from the Peruvian Andes. PeerJ 4:e2767 https://doi.org/10.7717/peerj.2767