Serpent (Coatl)

Coatl, the serpent, takes its augury from the animal's own visible habit of shedding its skin and continuing on renewed, and the tonalamatl's readers took the day for movement and exchange rather than for the animal's more common association with venom or danger in later, non Mesoamerican symbolism. Sahagun's fourth book records that 1 Coatl was among the days the pochteca, the long distance merchants whose trading expeditions carried goods and news across Mesoamerica, favoured for setting out on the road, a specific, practical use of the augural calendar that shows the tonalpohualli functioning as working knowledge for merchants rather than only as abstract fate telling for births.

The serpent's renewal symbolism connects this sign to a wider Mesoamerican reverence for the animal that appears far beyond the calendar itself, most visibly in Quetzalcoatl, the feathered serpent, though Coatl as a day sign is not itself identified with that god directly, its patron instead being a water goddess whose own domain, flowing rivers, offered a comparable image of constant motion and renewal. A day of movement and exchange, Coatl's reading fits naturally beside its own trecena, Trecena 9, whose overall augury for merchants and travel the day sign's individual character reinforces rather than complicates.

Coatl's patron is Chalchiuhtlicue, she of the jade skirt, goddess of lakes and flowing rivers, whose connection to water in constant motion matches the serpent's own reading for movement and renewal directly, a day sign and patron pairing among the more thematically coherent in the whole count. Its direction is east, the fifth day sign to carry that direction after Cipactli, Coatl standing exactly five places on from the count's opening sign in the four direction rotation shared also with Acatl and Ollin.

Coatl is not a year bearer, falling between Calli at the third position and Tochtli at the eighth, neither of which it borders closely enough to share their civic role in the solar calendar, so its influence stayed within the 260 day tonalpohualli. Chalchiuhtlicue's patronage here as a day sign governor is a separate office from her standing as the sixth of the nine Lords of the Night, the two systems, day sign patrons and night lords, assigning her duties independently of one another across the calendar's several layered registers, a structure typical of how the more prominent deities in the Mexica pantheon accumulated more than one distinct calendrical post. Chalchiuhtlicue's own presiding role over the Sun of Water, the fourth cosmic age the Legend of the Five Suns says ended in a flood that turned its people to fish, gives her patronage of a serpent sign already read for renewal a further layer, water's power to end an age as well as to sustain a single life.