MESOCLEMMYS RANICEPS (Amazon Toad-headed Turtle). PHENOTYPIC CHANGE.

Abstract

For nearly two decades, the question of the validity of Mesoclemmys heliostemma in relation to that of Mesoclemmys raniceps has been a source of uncertainty. M. heliostemma was (likely incorrectly) “revalidated”. A notable publication described a range extension of the two taxa in sympatry, with the color morph “M. heliostemma” on the right margin of the Jutaí River and M. raniceps on the left margin of the Jutaí River, both in the Municipality of Jutaí, Amazonas, Brazil. We present a series of images of juvenile animals exhibiting the morph color “M. heliostemma” phenotype. We provide a temporal series of a M. raniceps hatchling that displays vibrant yellow-orange facial stripes in the dorsolateral region of the head, starting at the base of the neck and extending to the tip of the snout, similar to the paratype RMNH 31998 of morph color “M. heliostemma”.