The Wagon Wheel Mushroom has a unique look and distinctive color pattern, offering diversity to a mushroom coral collection!
The Wagon Wheel Mushroom Actinodiscus marmoratus is also known as Marbled Mushroom, Green Marbled Mushroom, Thick Striped Mushroom, and Mottled Mushroom. These names are descriptive of this very pretty and unusual mushroom corals appearance. The surface of their oral disc is slightly rough with many bumps of a contrasting color. They can come in green, blue, or brown, but most commonly they are brown with green to blue marbled, radiating splotches.
Like most Actinodiscus mushrooms, the Wagon Wheel Mushroom or Marbled Mushroom Actinodiscus marmoratus typically reaches only 2-3″ (5-8 cm). In nature they primarily feed off suspended micro particles from the water column. Although they do not have the long feeding tentacles to capture prey like those found in sea anemones and stony coral, their pimples serve them well by holding several types of stinging cells.
The A. marmoratus is a great coral for beginners to advanced aquarists. It is one of the most recognizable mushrooms and though a bit costly, most stores carry them on a regular basis. Their fluorescent green totally pops out under the actinic lighting and will be very eye catching in your display. There is no need to feed them in captivity as they will take what nutrients they need from the water. Due to their small size, they are a great addition to any nano tank or any larger sized tank as well.
The Wagon Wheel Mushroom Actinodiscus marmoratus propagates easily in captivity, though after splitting the clone mushroom doesn’t necessarily always resemble the “mother” mushroom, thus giving the aquarist a variety of shades and colors. They are semi-aggressive. If they are near another coral they will cause them to loose tissue, recess, and possibly die. Acroporas will not grow in aquariums with large mushroom populations. A. marmoratus have very few predators if any.
Species: Actinodiscus marmoratus, Syns: Actinodiscus marmorata, Discosoma marmorata
Distribution / Background
Mushroom Coral Information: The Wagon Wheel Mushroom Actinodiscus marmoratus was discovered by Ruppell and Leuckart in 1828. Some names they are known for are Marbled Mushroom, Green Marbled Mushroom, Thick Striped Mushroom, and Mottled Mushroom. Some general names for these are Mushroom Coral, Mushroom Anemone, Disk Anemone, Mushroom Rock Actinodiscus, Coral-like Anemone, False Anemone, Jewel Anemone, Shroom, and Mushroom.
As far as current taxonomy, the A. marmoratus is listed under Actinodiscus and not Discosoma, according to the 2007 taxonomy list. The taxonomical identification of mushroom corals has a history of limited and dated information which is often of dubious value and sometimes incorrect. Mushrooms corals have no fossil records and studying the physical aspects has proved to be not very reliable for identification. Modern methods using DNA and RNA testing to deduce the sequence of genes, though more reliable, is not readily available.
Where Mushroom Corals Are Found: The Actinodiscus marmoratus are found in the Indo-Pacific Ocean from East Africa to the Central Pacific Ocean.
Mushroom Coral Habitat: The Wagon Wheel Mushroom or Marbled Mushroom is generally found in less than 16 feet (5 m) of water. They prefer shallow lagoons and tide pools, but can at times be found in out reef slopes. They like to grow on dead corals, rubble, and between coral heads. They feed off micro particulate matter in the water column. A. marmoratus propagates easily in captivity, which can contribute to preserving the wild populations. Even after splitting, the clone mushroom doesn’t necessarily always resemble the “mother” mushroom, thus giving the aquarist a variety of shades and colors. They have very few predators if any.
The Actinodiscus marmoratus is not on the IUCN Red List for endangered species
What do Mushroom Corals look like: The Wagon Wheel Mushroom Actinodiscus marmoratus are basically a coral without a skeleton and their internal structures are the same as stony corals. The top of their body or the upper surface is called the oral disc. The surface of the oral disc is slightly rough, with many bumps of contrasting color. The stalk area, which is very small, is called the column and it is located just above the pedal disc, which is where they attach to surfaces.
The A. marmoratus come in green, blue, brown, but most commonly they are brown with a green to blue marbled radiating splotches. They have little pimples instead of the long feeding tentacles to capture prey, although their little pimples serve them well by holding several types of stinging cells. They can actually warp the surface of their oral disc to change the water flow over them to direct particulate and flocculent material toward their mucous center for absorption. At times they will make a trumpet shape. This is thought to be formed when they are needing nourishment, or if the light level is low, or is of low quality due to age.
Mushroom Coral Life Cycles: The Wagon Wheel Mushroom or Marbled Mushroom can grow to can grow to 2-3″ (5-8 cm), but their life span is unknown.
Difficulty of Care
Mushroom Coral Care: The Wagon Wheel Mushroom is easy to care for and does not like or need high levels of light. They should be kept in shaded areas in tanks with high output lamps. If they are not shaded, they turn all brown and fail to thrive. Some will just float around the tank until they find a nice shaded area or have an unpleasant encounter with a pump. They also cannot handle high or high to moderate water flow. But they can handle higher levels of nitrate than SPS and LPS corals.
Foods / Feeding
Mushroom Coral Feeding: The Wagon Wheel Mushroom or Marbled Mushroom is a carnivore. In the wild, these corallimorphs are well equipped with nutritional alternatives for their well-being. They derive nutrition from their symbiotic algae, zooxanthellae, that dwells within their tissues and they eat suspended micro particles out of the water column. They can actually warp their surfaces to change the water flow over them to direct particulate and flocculent material toward their mucous center for absorption.
In captivity you can feed your A. marmoratus newly hatched artemia once in a great while. But really, it is the nutrient level in your tank that they will thrive in, and not direct feedings.
Water changes of 10% bi-monthly or 20% a month are typical. Provide a reef environment with proper magnesium levels. Some claim proper iodine levels are beneficial also. Due to their toxins, active carbon is a good idea with larger colonies of mushrooms. Do not over skim since the A. marmoratus need nutrients to survive on and will not do well in a pristine environment.
A typical live rock/reef environment is what is needed for your Wagon Wheel Mushroom or Marbled Mushroom. Provide rubble or dead coral and live rock for them to have something with which to attach their pedal disc. They do not do well with strong water movement, so direct the power heads and intake nozzles away from them. As they can float around when looking for a place to settle, it’s a good rule of thumb to have all of your pumps covered. Most good quality pumps have guards on them.
- Minimum Tank Size / Length: Nano tank of 1 gallon or more
- Marine Lighting: Low, does not like direct metal halide lighting
- Temperature: 72° – 83° F (22° – 28° C)
- Salinity / Specific Gravity: 1.023 to 1.025
- Water Movement: Low / weak
- Water Region: Bottom of the aquarium
Compatibility and Social Behaviors
The Wagon Wheel Mushroom or Marbled Mushroom is semi-aggressive if they are near another coral. They will cause other corals to loose tissue, recess possibly die. Acroporas will not grow in aquariums with large mushroom populations. Make sure to leave 6 – 8 ” between your mushrooms and other corals. Watch the growth rate since the A. marmoratus will overgrow and kill any nearby corals.
Mushroom Anemones will tolerate their own species and usually other Mushrooms. In the wild many species of Mushroom Corals occur together in large groups. In captivity A. marmoratus will get along with their own species, but may not tolerate mushroom species outside their colony. Even in one genus, if the color is different or a different species, the weaker mushroom will detach and find another location. Strong water movement will cause them to detach as well.
Sex – Sexual differences
No sexual difference in appearance is known.
Breeding and Reproduction
- Mushroom Coral Reproduction:
Corallimorphs reproduce in 4 different ways. The first three ways, asexual budding, laceration, and division/fission, are successful in the aquarium as most hobbyists soon discover. Budding is where individuals are formed from particles divided off from the pedal disc. Similar to budding, laceration happens when they move slowly over the surface and leave behind small pieces that will eventually form into mushrooms. Division or fission is where an individual divides down the center and forms two animals.
Sexual reproduction is where eggs and sperm are released into the water column. They unite and form free-swimming larvae which are initially plankonic, and them settle and adhere to the substrate. Sexual reproduction has not been well documented, and has not been observed in captivity. Presumably modern filtration methods are inhospitable to free swimming larvae.
- Mushroom Coral Propagation:
Mushroom corals can be easily propagated in captivity by cutting individual polyps into several pieces. Placed the pieces on a gravel substrate with low water flow. They will attach themselves to pieces of gravel. Later they can then be super glued to a suitable substrate such as a reef plug. It has been stated that the warmer end of their temperature spectrum encourages reproduction.
For details on how to propagate your mushroom corals see Mushroom Corals: Mushroom Coral Propagation
The A. marmoratus are disease resistant, and only affected by improper husbandry. Problems for the most Corallimorphs are pretty minimal unless your lighting, water movement, feeding and water quality are improper for these animals. A sign of this is if your coral mushroom detaches to look for “better conditions” to settle in. They have very few predators if any.
Mushroom Corals for Sale: The Wagon Wheel Mushroom, Marbled Mushroom, Thick Striped Mushroom, or Mottled Mushroom A. marmoratus, though a bit costly, is often available as most stores carry them on a regular basis or will special order them. You may also find them online as well as from reef clubs and coral frag groups. Online they are $54.00 USD or more depending on the size of rock they are on, and their color.
- Animal-World References: Marine and Reef
- Eric Borneman, Aquarium Corals : Selection, Husbandry, and Natural History , TFH Publications, 2001
- Anthony Calfo, Book of Coral Propagation, Volume 1 Edition 2: Reef Gardening for Aquarists, Reading Trees; 2 edition, 2007
- Ronald L. Shimek, Guide to Marine Invertebrates: 500+ Essential-to-Know Aquarium Species, Microcosm, 2005
- Bob Goemans, Wagon-wheel/Marble Mushroom, Discosoma marmorata (Actinodiscus marmorata, Animal Library, Saltwatercorner.com
Featured Image Credit: Roger Asbury, Shutterstock