Soft Coral Mushroom Information

Note the tentacles extending from this coral polyp.

Corals are in the animal kingdom. Soft corals don't have the outer skeletons of their hard counterparts. Soft mushroom corals display properties unique to both the animal kingdom and even other soft corals, thus they have their own genus; Heliofungia actiniformis . While coral is relatively common throughout marine environments, soft mushroom coral exist in specific regions. They are subject to the same habitat threats of all coral species.

Identification

Identifying a specific coral genus by sight involves training and experience. Generally, a mushroom coral is flat with green or purple tentacles extending out in all directions. It's one of the largest coral species, known to grow 10 inches or larger. The center has a mouth shaped slit that's surrounded by stripes that are most often black and white. Once, mushroom corals were part of the genus Fungia, until scientists found the polyp structure differs from these varieties. Tentacles on soft corals arrange in groups of eight, instead of groups of six as with hard corals according to National Oceanic and Atmospheric (NOAA) website.

Features

A polyp is the building block of coral that forms when larvae attaches itself to a hard surface. Most varieties of coral live in polyp colonies; however, the mushroom coral is free floating as an adult. Tentacles, which grow off the polyps, reach out to snag, sting and bring prey into the coral's mouth. Most often, soft corals reproduce through asexual budding--also called cloning. An anatomy of a soft coral is simple, as explained by a Florida University of Technology website; they ingest through the mouth where prey then proceeds through the pharynx into digestive organs.

Geography

Documenting of mushroom corals happens primarily in areas around Indonesia, the Philippines and Australia. They like warm, shallow waters, where currents carry food to within their reach so they can snatch it with their signature tentacles. The unusual habit of a single polyp breaking off, instead of forming and living in colonies, sometimes make this variety difficult to find, despite its' size.

Significance

A fall 2005 issue of Research Horizons explains how researchers see the potential for beneficial drug development in soft corals, including the mushroom variety. Soft corals are valuable to the aquarium industry. According to a College of Micronesia information sheet, mushroom corals are "the hardiest and easiest soft corals to grow" in aquarium environments. Their presence or lack thereof, is an indicator of overall aquatic environment health.

Threats

Since soft corals don't rely on calcium carbonate formation to create hard outer skeletons, the effects of ocean acidification are not as harsh as with hard coral reefs. Destructive fishing practices such as dredging and dynamiting destroy both the coral and their habitat. Other human practices, including logging, oil drilling and general pollutio, also threaten mushroom polyps.

References

• National Oceanic and Atmospheric Administration: Coral Anatomy and Structure
• Florida Institute of Technology: Scleractinian Taxonomy
• Research Horizons: Reefing The Benefits
• Farming Soft Corals For The Marine Animal Trade