Isthmian script

Isthmian script
Detail showing three columns of glyphs from La Mojarra Stela 1. The two right columns are Isthmian glyphs. The left column gives a Mesoamerican Long Count calendar date of 8.5.16.9.7, or 156 CE.
Script type
Undeciphered
(assumed to be logosyllabic)
Period
c.500 BCE  500 CE
DirectionTop-to-bottom 
LanguagesEpi-Olmec (ISO639-3:xep)

The Isthmian script is an early set of symbols found in inscriptions around the Isthmus of Tehuantepec, dating to c.500 BCE  500 CE, though with dates subject to disagreement. It is also called the La Mojarra script and the Epi-Olmec script ('post-Olmec script').

It has not been conclusively determined whether Isthmian script is a true writing system that represents a spoken language, or is a system of proto-writing. According to a disputed partial decipherment, it is structurally similar to the Maya script, and like Maya uses one set of characters to represent morphemes, and a second set to represent syllables.