Galea spixii (Wagler, 1831)

Species Naming and Origin

Spix's yellow-toothed cavy, with the scientific name Galea spixii, is a cavy species of rodent native to South America.

Geographic Distribution

It is found in Bolivia east of the Andes, and across most of south central to northeastern Brazil.

Habitat Preference

This species inhabits open savanna and semiarid habitats, including the Brazilian Cerrado and Caatinga.

Karyotype

Its karyotype is 2n = 64 and FN = 118.

Taxonomic Relationship

Galea spixii is similar to G. musteloides, and the two may actually be the same species.

Environmental Tolerance

Galea spixii tolerates a wide range of environmental changes, but requires open habitats.

Population Status

It is the most stable species within the genus Galea, as it is extremely abundant across its entire range.

Gestation Period

Gestation for this species lasts approximately fifty days.

Litter Size

Litter size ranges from one to five offspring, with an average of three.

Neonatal Traits

Young are born with hair and open eyes.

Sexual Maturation

Sexual maturation timing differs between the two sexes: female Galea spixii develop an open vagina at approximately 80 days old, while males complete testicular descent at around 135 days old.

Interspecies Social Behavior

Males and females of this species are aggressive toward each other, and notable paternal care is rare.

Estrus Related Aggression

Aggressiveness increases when females enter estrus.

Male Mating Competition

Males compete aggressively with other males when approaching females to mate.

Sperm Recovery Study Methodology

One Brazilian study placed nine male cavies euthanized to test sperm recovery, by either soaking or injecting sperm into a chemically buffered liquid.

Sperm Recovery Study Results

The study found no distinct differences in results between the soaking and injection methods.