Plica umbra ssp.

Taxonomic comments. Plica umbra ssp. has been confounded with Plica umbra ochrocollaris due to their sympatric distribution, but some differences in head scutellation and coloration qualify them as different taxa. Among others characteristics, it can be distinguished from P. umbra ochrocollaris by the absence of the pair of enlarged conical scales on the posterolateral corners of the interparietal, and from P. umbra umbra by the presence of a beige spot on sides of neck, followed by a black collar.

Distribution and habitat. Plica umbra ssp. is endemic to western Amazonia, with distribution presently restricted to upper Amazon/Marañon and their main tributaries, occurring in Brazil, Ecuador, and Peru (Fig. 16). In Brazil it is known from the states of Amazonas and Acre. Plica umbra ssp., as the other taxa of the umbra group, is arboreal and diurnal, inhabits primary and secondary terra firme forests, where it is found on trunks of small to moderate-sized trees (Ortega-Andrade, H.M. unpublished thesis; museum data).