In a groundbreaking study published in July 2024 in Frontiers in Amphibian and Reptile Science, Valeria Velasquez Cañon and her colleagues from the University of Caldas, Colombia, have explored the specialized sensory organs of aquatic garter snakes. Their research focuses on “sensillae,” distinctive dome-shaped protrusions on the skin of these snakes, which are believed to detect pressure and vibrations in their aquatic habitats.
The team examined the sensillae in three species of Helicops: Helicops pastazae, known for inhabiting rocky rivers and feeding primarily on fish, and Helicops danieli and Helicops angulatus, which are found in grassland floodplains with a varied diet including fish, frogs, and lizards.
Velasquez Cañon highlights a key discovery from their study: the sensillae are not evenly distributed but are predominantly located on the lateral sides of the neck. This suggests that these structures might be involved in the snakes’ hunting strategies, possibly indicating a lateral striking method.
The research also found that in Helicops species, where the vertebral scales exhibit a pronounced keel, the sensillae are arranged in a linear pattern along this keel. In contrast, the less pronounced keels on lateral scales have fewer sensillae.
This observation raises intriguing questions about the role of the keel in environmental sensing for these aquatic snakes. The study opens new avenues for understanding how these reptiles utilize their specialized sensory adaptations in their natural habitats.