Coastal Rosy Boa

Lichanura orcutti, also known as the rosy boa, the coastal rosy boa, or the northern three-lined boa, is a species of snake in the family Boidae. This species is found North of the US–Mexico border within San Diego County in California and along the coastal Peninsular Ranges, northward into the Mojave Desert and eastward in the Sonoran Desert of California and Arizona. Lichanura orcutti is one of four boa species native to the continental United States, the other three being the desert rosy boa (Lichanura trivirgata), and the two species of rubber boas (Charina).

Taxonomy

Zoologist Leonhard Stejneger described the species in 1889. Lichanura taxonomy is not well understood; some taxonomists have challenged the Lichanura genus and suggest that these species be grouped with Charina, the rubber boas. L. orcutti was previously considered to be a subspecies of L. trivirgata; DNA analysis later identified L. orcutti as a distinct species. Confusion over scientific names is compounded by the fact that Lichanura species are popular as pets and reptile keepers frequently use outdated taxonomy.

Description

Lichanura orcutti is a heavy-bodied snake with smooth scales and a tapered blunt tail. The head is marginally wider than the neck. It has vertical pupils. Adults can range from 17 to 44 inches (43 to 112 cm) in length, though they rarely exceed 36 inches (91 cm). Hatchlings are 10 to 14 inches long. Males typically have well-developed anal spurs.

This species has three stripes that run lengthwise down the dorsal and lateral aspects of the animal. These stripes may be tan, orange, brick red, or reddish-brown depending on locality; interspaces vary from blue grey to tan, yellow, or nearly white. Stripes vary from defined to ill-defined depending on the individual animal. The coloration of younger animals is typically lighter with more defined striping. Despite the name "rosy boa," most individuals do not have the rosy ventral coloration from which the species derives its popular common name.

Distribution and habitat

This species is found North of the US–Mexico border within San Diego County in California and along the coastal Peninsular Ranges, northward into the Mojave Desert and eastward in the Sonoran Desert of California and Arizona. This species also occurs in southern Nevada.

Habitat consists of arid scrublands, semi-arid shrublands, rocky shrublands, rocky deserts, canyons, and other rocky areas. This species may be more common in riparian areas such as oases and permanent or intermittent streams, but it does not require permanent water. The IUCN Redlist suggests that L. orcutti's affinity for rocky habitats unsuitable for development or agriculture may protect it from habitat loss.

Behavior and ecology