|Iwasaki's snail-eater (Pareas iwasakii)|
Many pareids are snail-eating snakes that have asymmetrical lower jaws, allowing them to pry the soft bodies of snails from their spiral shells. One species, Pareas iwasakii, has an average of 17.5 teeth in its left mandible and 25 teeth in its right mandible. Other species lacking asymmetrical jaws, such as Aplopeltura boa and Asthenodipsas malaccanus, feed instead on slugs or lizards. Predation by pareids on dextral (clockwise-coiled or "right handed") snails is thought to favor the evolution of sinistral (counter-clockwise or "left handed") snails in southeast Asia, where 12% of snail species are sinistral (as opposed to 5% worldwide).
Genera and species
- Aplopeltura boa, Blunt-headed Slug Snake
- Pyron, RA; Burbrink, F; Wiens, JJ (2013). "A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes". BMC Evolutionary Biology. 13: 93.
- Savage, JM (2015). "What are the correct family names for the taxa that include the snake genera Xenodermus, Pareas, and Calamaria?". Herpetological Review. 46: 664–665.
- Hoso, M; Asami, T; Hori, M (2007). "Right-handed snakes: convergent evolution of asymmetry for functional specialization" (PDF). Biology Letters. 3: 169–172.
- Hoso, M; Kameda, Y; Wu, SP; Asami, T; Kato, M; Hori, M (2010). "A speciation gene for left-right reversal in snails results in anti-predator adaptation". Nature Communications. 1. doi:10.1038/ncomms1133.