Cerdocyonina


Cerdocyonina is an extant subtribe of the canini and is endemic to the Americas. It is a sister lineage to the subtribe Canina. There are 10 extant species. Its members are colloquially known as the South American canids.

Taxonomy

Cerdocyonina is a natural lineage whose common ancestor was sister to the Eucyon–Canis–Lycaon lineage. It is represented in the fossil record of North America by Cerdocyon 6-5 million years ago, and by Theriodictis and Chrysocyon 5–4 million years ago.
The fossil of a large form of the extinct Theriodictis that dates 2 million years ago was found in Florida. The maned wolf and an extinct species of the crab-eating zorro were in North America around this time, which was before the Isthmus of Panama came into being, indicating the origin of the Cerdocyonina in North America.
Prior to the 1990s there have been different systematic hypotheses pertaining to the relationships among South American canids, most frequent was the notion of there being three genera and subgenera after Langguth 1969 and 1970:
  • Genus Cerdocyon
  • * Subgenus Atelocynus
  • * Subgenus Cerdocyon
  • * Subgenus Speothos
  • Genus Dusicyon
  • * Subgenus Lycalopex
  • * Subgenus †Dusicyon
  • Genus Chrysocyon
Morphological and DNA evidence shows that the South American canids, being the most diverse group of canids on any continent, forms its own natural group.
In 2018, a study found that the extinct South American Canis gezi did not fall under genus Canis and should be classified under the Cerdocyonina, however no genus was proposed.

Genetic lineage

In 2005, a genetic study revealed the cladogram below, modified to incorporate recent findings on Lycalopex species and Dusicyon.

Common ancestor

In 2022, a study sequenced the genomes of the living members of Cerdocyonina, which indicates that they commenced diversifying from a common ancestor between 3.9—3.5 million years ago. This finding is consistent with the ancestor arriving in South America from Central America through the Isthmus of Panama and then entering into eastern South America. The subtribe then expanded to occupy the entire continent.