A marine biologist from Scripps Institution of Oceanography has discovered a new species of chaenopsid blenny in the waters around Cocos Island (Isla del Coco), which lies about 563 km (350 miles) off the Pacific coast of Costa Rica.
Blennies are a group of over 900 species of fishes found in coastal areas throughout the world’s oceans.
They are generally small, and have elongated bodies and relatively large eyes.
The newly-discovered species of blenny, scientifically named Coralliozetus clausus and dubbed the pandemic blenny, is one of several cryptobenthic species found off Cocos Island.
These fishes dwell on the seafloor and are extremely hard to detect and quantify because of their small size and coloration and habits.
“Although I had known that the form on Cocos Island differed from those from mainland Costa Rica, I needed to fully evaluate morphological variation in the mainland species throughout its range to be certain that the two differed,” said Dr. Phil Hastings, a researcher at Scripps Institution of Oceanography.
“That required careful examination under a dissecting scope because these species are so small.”
Coralliozetus clausus is a short-bodied member of the genus Coralliozetus, not exceeding 1.5 cm (0.6 inches) in length.
It is the second chaenopsid blenny endemic to Cocos Island, and brings the number of reef-associated cryptobenthic fishes endemic to the island to twelve.
That number includes gobies, clingfishes, members of other groups of blennies and another blenny, the Cocos barnacle blenny (Acanthemblemaria atrata), described by Dr. Hastings and colleagues in 1999.
“Thankfully the protected status of Isla del Coco and the waters surrounding it bode well for the conservation of these small fishes found nowhere else in the world,” Dr. Hastings said.
His paper was published in the journal Zootaxa.
Philip A. Hastings. 2021. The Pandemic Blenny, Coralliozetus clausus, a new species of tube blenny endemic to Isla del Coco, Costa Rica (Teleostei: Chaenopsidae). Zootaxa 4926 (2); doi: 10.11646/zootaxa.4926.2.10