Cape Thread Snake

Cape Thread Snake, Rene boettgeri

Cape Thread Snake, Rena boettgeri. Snake collected from a residential swimming pool in the greater Los Cabos area, Baja California Sur, August 2020. Length: 20.8 cm (8.2 inches). Catch courtesy of Mauricio Correa, Los Cabos, Mexico. Identification courtesy of Gary Nafis, CaliforniaHerps.com.

The Cape Thread Snake, Rena boettgeri, is a member of the Leptotyphlopidae Family of Thread Snakes or Worm Snakes.  The Leptotyphlopidae family consists of ninety members placed in two genera. There are ten global species in the Rena genus. They are also known as the Blind Snake and the Cerralvo Island Thread Snake. The Cape Thread Snake is known in Mexico as Culebrilla Ciega de Isla Cerralvo.

Cape Thread Snakes are small and slender in stature and are disproportionately longer than they are wide. Cape Thread Snakes are a uniform brown or purplish color dorsally, transitioning to off white ventrally. Their rostral is rounded at the back and is about 33% the width of their head. Their very small eyes are not well-defined, giving rise to the common name Blind Snake. They have 4 lower lip shields, 14 rows of midbody scales, 10 rows of midtail scales, and 9 to 21 rows of mid dorsal scales. They have moderate to large anterior supralabial scales. They reach a maximum of 22.5 cm (8.9 inches) in length and have short tails that are 5% of their total length. 

Cape Thread Snakes are a burrowing species and spend the majority of their time underground. They are diurnal and primarily consume insects. Reproduction is oviparous. The Cape Thread Snake is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Cape Thread Snake is Endemic to Mexico and has an extremely limited distribution, being found only south of La Paz and Todos Santos at the lower elevations of southern Baja California Sur and on Cerralvo Island within the Sea of Cortez. They primarily inhabit dry coastal chaparral.


From a conservation perspective, the Cape Thread Snake has not been formally evaluated. However, due their limited distribution they should be considered Vulnerable. They are not considered to be dangerous to humans, as they are non-venomous or possess only a mild venom.