The short-eared dog (Atelocynus microtis), short-eared fox or small eared zorro is a unique and elusive canid species endemic to the Amazonian basin.

Other common names in Spanish include ' ("blue-eyed fox"), ' ("savannah fox"), and ' ("black fox").

Evolution and systematics

thumb|left|In the Amazon rainforest

In 2022, a study sequenced the genomes of the living members of the subtribe 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. It is one of the most unusual canids. It is a solitary animal and prefers to remain under tree-cover, avoiding both human and other animal interaction.

Appearance

thumb|upright|Short-eared dog fur skin (Atelocynus microtis), fur skin collection, [[Senckenberg Museum|Bundes-Pelzfachschule, Frankfurt/Main, Germany]]

thumb|upright|Short-eared dog skull

The short-eared dog has short and slender limbs with short and rounded ears. It has a distinctive fox-like muzzle and bushy tail. Its paws are partly webbed, helping adapt it to its partly aquatic habitat.

Its fur ranges from dark to reddish-grey, but can also be nearly navy blue, coffee brown, dark grey, or chestnut-grey to black, and the coat is short, with thick and bristly fur.

The lifespan and gestation period of the short-eared dog are unknown, although sexual maturity is reached at three years of age, relatively late compared to other canid species.

Threats, survival, and ecological concerns

Feral dogs pose a prominent threat to the population of short-eared dogs, as they facilitate the spread of diseases, such as canine distemper and rabies, to the wild population. The short eared dog suffers greatly from loss of habitat. There is a significant amount of disturbance in formerly remote South American forests, and almost no habitat except where daily human settler and prospector traffic destroys or exposes their dens. Humans also contribute to their extermination by degradation of the species' natural habitat and the general destruction of tropical rainforests.<!-- Scientists still have little knowledge of its biology. -->

Status of conservation

The short-eared dog is currently considered near threatened by the IUCN.