The LanceletAsymmetron lucayanumComplex in Cocos Island National Park, Pacific Costa Rica

Researchers document the first occurrence of the lancelet Asymmetron lucayanum complex in the eastern Pacific, specifically within Cocos Island National Park. This discovery is significant as it expands the known distribution of this circumtropical species, which was previously unrecorded in the region. The study, conducted during a benthic survey, analyzed taxonomically significant characters such as myotome count and gonad placement to confirm the identification. Lancelets were found in subtidal sandy bottoms (5–42 m) with slightly gravelly, poorly sorted sediment. This finding contributes valuable baseline data for understanding marine biodiversity in this remote and ecologically important site.

Sibaja-Cordero, J. A., Troncoso, J. S., & Cortés, J. (2012). The LanceletAsymmetron lucayanumComplex in Cocos Island National Park, Pacific Costa Rica. Pacific Science, 66(4), 523–528. https://doi.org/10.2984/66.4.9