California red-sided garter snake

The California red-sided garter snake (Thamnophis sirtalis infernalis) is a subspecies of the normal garter snake. This slim subspecies of natricine snake is native to North America and one of three recognized subspecies of Thamnophis sirtalis in California. While generally complicated with the subspecies T. s. concinnus, it is biologically part of the inhabitants of the subspecies T. s. tetrataenia, as indicated out by Boundy and Rossman (1995) but was kept as T. s. infernalis as a neotype under ICZN code Article 75 in a 2000 result by the International Commission on Zoological Nomenclature (ICZN) to maintain the existing subspecies taxonomy.

California red-sided garter snake

Most California red-sided garter snakes have blue stripes on a black and red background. Their overall length averages around 55 cm (22 in), with a maximum of about 100 cm (39 in).

Description

Thamnophis sirtalis infernalis has a basic pattern of three stripes, containing yellow or blue stripes over a predominantly red body, with a row of black spots or blotches forming a stripe-like pattern. The red can be more or less visible depending on the specimen, but it appears as scars and spots all over the body and head. In rare circumstances, the red may be less noticeable, and the snake seems to be black with red marks. However, T. s. infernalis can be clearly identified from the San Francisco garter snake, which has similar in colour. Still, it exhibits red streaking and spots rather than a single strip of red alongside the dorsal stripe. The subspecies has an orange or red head and varies substantially in appearance depending on the snake's geographical region.

California red-sided garter snake

The California red-sided garter snake is a slimmer, lighter snake than the San Francisco garter snake. Females often reach 90-100 cm (35-39 inches), while males average 65-75 cm (25-29.5 inches) and are significantly slimmer than females. While the documented maximum size for T. sirtalis as a species is 137 cm (53.9 inches), it is rare to find a female T. s. infernalis exceeding 100 cm (39.5 inches).

Taxonomy

There needs to be more clarity over T. s. infernalis' subspecific name. Boundy and Rossman (1995) identified naming issues with Pacific Coast populations of the Thamnophis sirtalis subspecies. However, the International Commission on Zoological Nomenclature (ICZN) denied suggestions that the subspecies T. s. tetrataenia be referred to as T. s. infernalis and that the current subspecies T. s. infernalis be included with the subspecies T. s. concinnus in 2000. A neotype for T. s. infernalis was designated to conserve the traditional subspecies taxonomy.

Reproduction

Thamnophis sirtalis infernalis is a viviparous snake that mates in late winter/early spring. Live young are born in the mid-summer to early autumn and normally measure 12-20 centimetres (5-8 inches) in length. Clutch sizes vary, but they usually range from 8 to 20 young.

California red-sided garter snake

Like the red-spotted garter snake (T. s. concinnus), young T. s. infernalis have faint colors that gradually brighten as the snake matures and sheds. Most young snakes are born yellow and gradually turn blue as they mature and shed.

Distribution

Thamnophis sirtalis infernalis lives throughout California, mainly in coastal dunes and marshlands. Its distribution is discontinuous, reaching from coastal Humboldt County to coastal Monterey County, and it coincides with some San Francisco garter snakes. However, in southern Monterey, T. s. infernalis has been largely replaced by another subspecies of the frequent garter snake, the valley garter snake (T. s. fitchi), resulting in their absence from Monterey to Santa Barbara but presence from Santa Barbara to San Diego County. The subspecies was designated as endangered under the United States Endangered Species Act (USESA) of 1967, and the United States Fish and Wildlife Service listed it as decreasing in 1990.

Habitat

Thamnophis sirtalis infernalis is commonly found in enduring or near-lasting bodies of water such as shallow water, marshland, and dunes. Its major habitat is sag ponds in the San Andreas Oversight rift zone and freshwater coastal marshlands. T. s. infernalis also appears momentarily in grassland and some woods.

Conclusion

The California red-sided garter snake is a North American subspecies that lives predominantly along California's coast. It has a distinct coloration pattern, with blue stripes on a black and red backdrop. The subspecies is taxonomically confused, but a neotype identification in 2000 maintained its categorization. It is viviparous, mating in late winter/early spring and giving birth to live offspring between mid-summer and early autumn. The snake is endangered and ranges from Humboldt to Monterey County, with threats in some areas. Its habitat includes marshlands, sag ponds, and coastal areas, highlighting the significance of conservation efforts for this unique garter snake.