Palm Tree Polyps
Clove Polyps, Glove Polyps, Fern Polyps, Waving Hand PolypClavularia Sp.Photo © Animal-World: Courtesy David Brough
The gorgeous Palm Tree Polyps is just one example of the eye-catching, easy care corals in the Clavularia genus!
True to its name, the Palm Tree Polyps C. viridis has tentacles that actually look like palm fronds. Each tentacle is surrounded by a feathery structure or pinnule. Their colors can be tan and at times have a yellow and/or green color to the middle of the tentacles. Some other common names the Palm Tree Polyps are known for are Clove Polyps, Palm Tree Polyps and Fern Polyps.
The Palm Tree Polyps is just one of the Clove Polyps in this intriguing Genus. These encrusting mat-like corals form flat, unlayered connecting stolons in a mesh-like structure which contains the polyps. These mats can be pale brown, gray, or tan in color. Their polyps are housed in tubular calyces that are .5 to 2" tall (1 to 5 cm), depending on the species. They have 8 tentacles and come in a variety of colors such as green, purple, yellow, white, brown, pinkish cream, or cream with centers that can also be contrasting colors. The polyps can retreat completely into the base of their individual calyx.
Most Clavularia species have tentacles with long feathery pinnules, or side branches, that can be very lush. They can also look like a solid "feather" with stiffer "plumes". All species have tentacles of varying length and some species have a more tubular or thick tentacle. With the wide variety of texture and color, the Clavularia corals can make a wonderful collection worth pursuing for an attractive reef aquarium.
The Clavularia corals can sometimes be confused with the Waving Hand Corals Anthelia sp., such as A. glauca, which has very similar polyps. You can tell the difference between the two by looking at them when the polyps are retracted. Clavularia can completely retract its polyps until only the closed heads of each calyx can be seen. Anthellia can deflate its polyps too, but one can still see the tentacles as they cannot be withdrawn completely into the calyx.
The Clavularia genus is very easy to care for and can be recommended for beginners. They are very useful in taking organics out of the water which can help water quality. But be cautious of hair algae as it can smother Clavularia corals. These corals will grow quickly covering the substrate upon which it lives, and covering everything in its path. Some use these corals to cover up equipment or the back wall of the aquarium. At the same time, their spreading needs to be monitored and kept away from the main rock work if there are other corals living there.
To learn about different types of soft corals, see:
Soft Coral Facts
Distribution / Background Soft Coral Information: The Clavularia genus was described by de Blainville in 1930. There are about 40 or more species including C. alba, C. arctica, C. armata, C. carpediem, C. crassa, C. flava, C. fusispora, C. grandiflora, C. griegii, C. hamra, C. hippotrichoides, C. inflata, C. levidensis, C. longissima, C. marioni, C. modesta, C. morbesbii, C. mycogena, C. notanda, C. novaezealandiae, C. pennicola, C. stenospora, C. thompsoni, C. tubaria, C. venustella, and C. viridis.
Out of all of these species, only one is an Atlantic Ocean species and that is C. modesto. Some common names the Clavularia corals are known for are Clove Polyps, Glove Polyps, Palm Tree Polyps, Brown Daisy, and Fern Polyps. The Clavularia genus has been propagated in captivity.
The common names for the Palm Tree Polyps C. viridis include Clove Polyps, Palm Tree Polyps and Fern Polyps. Due to a long history of confusion, the Green Star Polyps Pachyclavularia violacea has been incorrectly called Clavularia viridis. But looking at the descriptions and pictures of each, you will quickly see that Star Polyps do not fit with the Clavularia "glove" appearance. A notable visual difference is that Star Polyps have straight simple thin tentacles rather than the feathery pinnae of the Clavularia that can be very lush.
Where Clavularia Corals Are Found: The Clavularia genus are found in the Indo-Pacific with one species, C. modesto, being found in the Atlantic Ocean..
Clavularia Coral Habitat: The Clavularia genus are found in most areas throughout the reef but are more common on back-reef slopes, fore-reef slopes, and rubble zones with tidal currents.
Description What do Clavularia Corals look like: The Clavularia genus is an encrusting mat-like coral. They form mats that are flat, unlayered and connect to form a mesh-like structure which contains the polyps. All the polyps are housed in tubular calyces that are .5 to 2" tall (1 to 5 cm). The polyps can retreat completely into the base of their individual calyx.
The mats of the Clavularia corals can be brown, gray or tan. They have 8 tentacles and the polyps come in a variety of colors such as green, purple, yellow, white, brown pinkish cream or cream. The centers can also be contrasting colors. Most species have tentacles with long feathery pinnae that can be very lush. They can also look like a solid "feather" with stiffer "plumes" and all species have tentacles of varying length. Some species have a more tubular or thick tentacle. Not to be confused with Star Polyps that have straight thin tentacles.
Palm Tree Polyps C. viridis has tentacles that actually look like palm fronds. Each tentacle is surrounded by a feathery structure or pinnule. The colors can be tan and at times with a yellow/green color to the middle of the tentacles.
Difficulty of Care Soft Coral Care: The Palm Tree Polyps C. viridis is very easy to care for and can be recommended for beginners. The only major requirements are a moderate to strong and turbulent water flow and the additions of trace elements. Most lighting is acceptable, but they must be adapted to Metal Halides. They are very useful in taking organics out of the water which can help water quality.
It has been noted that they react poorly to Aluminum Oxide in some Phosphate removing media. Be cautious of hair algae as it can smother Clavularia corals. This coral can also irritate any adjacent zoanthids so keep them in separate parts of the aquarium.
Foods / Feeding Soft Coral Feeding: In the wild, Clavularia corals have developed several feeding strategies. They can absorb dissolved organic matter from the water column, and have a symbiotic relationship with a marine algae known as zooxanthellae, where they also receive some of their nutrients.
In captivity, the Palm Tree Polyps have not been observed actively feeding. Rather they will use light and their zooxanthellae for a food source, and will absorb micro particles from the water.
Aquarium Care Stable tank conditions are needed to keep the Clavularia genus. Doing water changes of 20% a month or 10% biweekly is needed, although it is suggested that doing 5% water changes once a week will replenish many of the needed additives. Calcium and other trace elements can be added to maintain proper levels for good growth. They can be sensitive to the aluminum oxide in some phosphate removing sponges.
Suggested levels for Clavularia species are:
- Calcium: 400 - 450 ppm
- Alkalinity: 3.2 - 4.8 MEQ/L (8 to 11 dKh - 10 is recommended)
- Phosphates: 0, zero.
- Magnesium: 1200 - 1350 ppm. (Magnesium makes calcium available, so if your calcium is low, check your magnesium levels before adding any more calcium.)
- Strontium: 8 - 10
|Quick Reference Chart|
A typical live rock/reef environment is what is needed for your Palm Tree Polyps, along with some fish for organic matter production. The C. viridis is fast spreading, and adaptable to all areas of the aquarium.
Provide proper lighting and water movement. A moderate to strong and turbulent water flow is needed. Most lighting is acceptable, but they must be adapted to Metal Halides. Their hardy growth can be a bonus when used as a decorative cover for particular areas in the tank. Otherwise, It may be helpful to keep the colony on a rock that isn't connected to any of the rock work, or they may spread and take over some corals.
- Minimum Tank Size / Length: 10 gallon Nano (38 L) if kept trimmed, or larger
- Marine Lighting: Moderate to high (adapt to metal halides)
- Temperature: 72° - 81° F (22° - 27° C)
- Salinity / Specific Gravity: 1.023 - 1.025
- Water Movement: Moderate to strong, and turbid
- Water Region: All areas of the aquarium
Compatibility and Social Behaviors The Palm Tree Polyps is peaceful and gets along with others of the same genus. They are not affected by the sting of other corals, which is what enables them to grow over anything.
The Clavularia genus needs to be contained, or it will over grown nearby corals. They can be put on a rock with sand around it with at least 4" or more of space between them and the main rock work. Still, keep an eye on them if you have a lot of rubble in your substrate, since they can pretty much anything. They also have a chemical defense that keeps "grazers" away so they should be fine with some of the polyp eating type of saltwater fish.
Propagation is easy, simply cut off pieces of a mat and glue them, or better yet, rubber band them to a rock or plug. You can also train them to spread onto rubble that can be easily snipped apart as needed. It can then be adhered to all sorts of surfaces like the aquarium glass and overflows, to create a living decorative cover.
Potential Problems The Clavularia genus is hardy and very easy to care for. However they are susceptible to detritus collecting and algae growing in-between their stalks. They need water that is at least moderate and turbulent enough to keep them blown them off on a regular basis.
- 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; 2nd edition, 2007
- Harry Erhardt and Horst Moosleitner, Marine Atlas Volume 2, Invertebrates (Baensch Marine Atlas), Mergus Verlag GmbH, Revised edition, 2005
- Ronald L. Shimek, Guide to Marine Invertebrates: 500+ Essential-to-Know Aquarium Species, Microcosm, 2005
- Bob Goemans, Clove/Palm Tree/Fern Polyps, Animal Library, Saltwatercorner.com