The San Francisco garter snake (Thamnophis sirtalis tetrataenia) is a slender multi-colored subspecies of the common garter snake. Designated as an endangered subspecies since the year 1967, it is endemic to San Mateo County and the extreme northern part of coastal Santa Cruz County in California. Some researchers estimate that there are only 1,000 to 2,000 adult snakes of the subspecies T. s. tetrataenia remaining. However, the full extent of the snakes' habitat has not been fully documented, and many snakes may utilize creeks and other waterways that are currently unexplored. This garter snake prefers wet and marshy areas, and because of its elusive nature, it is difficult to see or capture.
- Original Name: "Thamnophis sirtalis tetrataenia"
- Series: Reptiles
- Country: Cambodia (R.P. Kampuchea)
- Year: 1987-09-09
- Subject: Animals
- Perforation: comb 12¾
- Printing: offset lithography
- Face value: 3 riel
- Number of catalogue Michel: KH 888