マヤ文字
A small number of artifacts found in the Isthmus of Tehuantepec show examples of another early Mesoamerican writing system. They can be seen to contain calendric information but are otherwise undeciphered. The longest of these texts are on La Mojarra Stela 1 and the Tuxtla Statuette. The writing system used is very close to the Maya script, using affixal glyphs and Long Count dates, but is read only in one column at a time as is the Zapotec script. It has been suggested that this Isthmian or Epi-Olmec script is the direct predecessor of the Maya script, thus giving the Maya script a non-Maya origin. Another artifact with Epi-Olmec script is the Chiapa de Corzo stela which is the oldest monument of the Americas inscribed with its own date: the Long Count on the stela dates it to 36 BCE.