A newly discovered species of reef coral hangs from the ceiling of undersea caves like a colony of petrified bats. The topsy-turvy coral resides in the biodiversity hotspot known as the Coral Triangle in the West Pacific.
The cave coral, named Leptoseris troglodyte, has other strange habits besides hanging upside down. The coral doesn't have the symbiotic algae, called zooxanthellae, that most other reef coral species depend upon for survival.
The stalactite-like home of the coral may explain why it doesn't keep algal amigos around. Without algae, the coral may grow slower and smaller which reduces competition among themselves for scarce cave roof real estate, suggested the coral's discoverer Bert W. Hoeksema of the Naturalis Biodiversity Center in the journal Zoo Keys. The lack of algae may also contribute to the small size of the cave corals which makes it easier for the coral to stay suspended on the cavern ceilings.
Understanding how the newly described species survives without symbiotic algae may help oceanographers understand the phenomenon of coral bleaching. When waters get too warm, algae die off and leave the coral looking like old white bones. As the world's oceans continue to warm up, finding solutions to the threats to coral may help save the reef ecosystems as well as the human fishermen and tourist diving industry that depend on them.