The Stoloniferans: Clove Polyps, Star Polyps, and Pipe Organ Corals
by: James W. Fatherree, M.Sc.
When biologists divide out the different types of corals and their kindred, one of the groups that is formed is called the Subclass Octocorallia. It's name is a giveaway when it comes to what sets them apart, as all of the members are corals that have a ring of eight tentacles circling their bodies (polyps). Within this group of eight-tentacled corals there is a sub-group called the Suborder Stolonifera, and these are the subject of this month's article. The members are most commonly known to aquarists as the clove ployps, the star polyps, and the pipe organ corals.
The vast majority of these are difficult to identify and classify, even for scientists working with them, but they do have some other common characteristics that distinguish them. Aside from having eight tentacles, the vast majority also have little side branches that arise from these tentacles. These tiny structures are called "pinnules" and they can give a tentacle a serrated look, or can even make it look more like a feather.
The stoloniferans also share a feature called a stolon (no surprise). This is a layer of tissue that connects all of the polyps in a stoloniferan colony, which typically forms durable mat-like encrustations or strands that attach to hard surfaces (although we'll go over a big exception in a minute).
So, with these bare basics covered, let's take a closer look at the three common types of stoloniferans that you'll be sure to come across in the hobby.
-The Clove Polyps (also called daisy polyps):
Clove polyps, most of which belong to the Genus Clavularia, typically have the fanciest-looking forms of the bunch, with beautiful pinnate tentacles that look like fluffy feathers. However, while these plume-like tentacles are present on the most frequently seen specimens in stores, there are a few that have rather plain, thin tentacles, as well. All sorts regularly come in shades of brown, green, cream, or yellowish, and the polyps sometimes have lighter-colored centers, too.
Regardless of the polyp form, many of these grow as colonies that are rather loosely connected (relative to their relatives) by stolons that are thin and web-like. The stolons run like little creeping vines from the bases of each polyp and are often spread out a bit and only interconnected here and there. But, this isn't always the case though, as they can be quite tightly arranged when a number of polyps are situated close together. Likewise, there are those that form small clump-like bases/mats, too.
Another feature is their ability to retract into themselves when bothered. Just brush one side of a colony with your finger and you'll see the whole thing "shut down", with the polyps quickly deflating like little balloons and disappearing from sight by folding into the lower portion of themselves. Then the stolons become clearly visible, with a little nub/stalk sticking up where each feathery polyp was. They often retract like this at night, as well, so you can take a look in the morning when the lights first come on and you'll see the same thing. Something that looks quite dead, but isn't. If they're healthy, just give it a minute and they'll start to slowly emerge.
As far as environmental conditions go, in general clove polyps can tolerate a broad range of lighting. There are numerous varieties that hail from different environments, but they'll all do fine in aquariums lit by anything considered coral-worthy, from V.H.O. fluorescents to metal-halide systems. So, you don't have to worry too much about where they'll go with respect to lighting requirements. But, if you want them to really thrive they'll need the most they can get, with moderate to bright illumination being the way to go unless you see signs that they may be over-illuminated, such as a failure to open up.
Currents should be moderate. If they are too low, detritus/sediment can accumulate on a colony's base/stolons, so the current needs to be at least strong enough to keep them cleared off fairly well. Conversely, if the current is too strong the polyps will tend to stay retracted to avoid be overly blasted. So, a good turbulent current that stirs the water around a colony is best.
Unlike many other corals, clove polyps aren't going to take any foods you may try to give them. Even fine, plankton-type foods and powders are unlikely to provide any sort of benefit. But, they'll be fine despite this, as long as the lighting is acceptable, so feeding them is one thing you don't have to worry about.
You don't have to fret too much when it comes to where to put a colony with regards to fighting, either. They're highly resistant to the stings of most corals so they'll likely be just fine in crowded conditions. They won't sting anything they touch either, with the possible exception of zoanthid polyps (reported in Sprung & Delbeek, 1997). However, they can simply overgrow other low-lying neighbors, so you'll probably need to pay more attention to other nearby specimens rather than the clove polyps themselves.
Yet another plus is that they can be reproduced/propagated very easily using either of two basic methods. The easiest thing to do is position a small piece of shell or rock right up against part of a colony and let it do the rest. Over time the colony will spread onto this piece of substrate, which can then be cut away from the rest of the colony and moved elsewhere. Just use a razor blade to do the severing and put the newly produced little colony in a suitable spot, or even in another aquarium.
Likewise, if you don't feel like waiting for part of a colony to overgrow something, you can use a razor to cut away a part of the colony and then attach it to a piece of substrate yourself. You can dab the "cutting" on a piece of paper towel to get most of the water off, then use some gel-type "superglue" to attach it to a suitable piece of rock or shell, etc. This is much faster, but takes a little more skill and technique, so I suggest you do some homework specifically on the propagation of soft corals prior to trying it. Once you get the hang of it, it is very easy to do over and over, though.
(CONT)
by: James W. Fatherree, M.Sc.
When biologists divide out the different types of corals and their kindred, one of the groups that is formed is called the Subclass Octocorallia. It's name is a giveaway when it comes to what sets them apart, as all of the members are corals that have a ring of eight tentacles circling their bodies (polyps). Within this group of eight-tentacled corals there is a sub-group called the Suborder Stolonifera, and these are the subject of this month's article. The members are most commonly known to aquarists as the clove ployps, the star polyps, and the pipe organ corals.
The vast majority of these are difficult to identify and classify, even for scientists working with them, but they do have some other common characteristics that distinguish them. Aside from having eight tentacles, the vast majority also have little side branches that arise from these tentacles. These tiny structures are called "pinnules" and they can give a tentacle a serrated look, or can even make it look more like a feather.
The stoloniferans also share a feature called a stolon (no surprise). This is a layer of tissue that connects all of the polyps in a stoloniferan colony, which typically forms durable mat-like encrustations or strands that attach to hard surfaces (although we'll go over a big exception in a minute).
So, with these bare basics covered, let's take a closer look at the three common types of stoloniferans that you'll be sure to come across in the hobby.
-The Clove Polyps (also called daisy polyps):
Clove polyps, most of which belong to the Genus Clavularia, typically have the fanciest-looking forms of the bunch, with beautiful pinnate tentacles that look like fluffy feathers. However, while these plume-like tentacles are present on the most frequently seen specimens in stores, there are a few that have rather plain, thin tentacles, as well. All sorts regularly come in shades of brown, green, cream, or yellowish, and the polyps sometimes have lighter-colored centers, too.
Regardless of the polyp form, many of these grow as colonies that are rather loosely connected (relative to their relatives) by stolons that are thin and web-like. The stolons run like little creeping vines from the bases of each polyp and are often spread out a bit and only interconnected here and there. But, this isn't always the case though, as they can be quite tightly arranged when a number of polyps are situated close together. Likewise, there are those that form small clump-like bases/mats, too.
Another feature is their ability to retract into themselves when bothered. Just brush one side of a colony with your finger and you'll see the whole thing "shut down", with the polyps quickly deflating like little balloons and disappearing from sight by folding into the lower portion of themselves. Then the stolons become clearly visible, with a little nub/stalk sticking up where each feathery polyp was. They often retract like this at night, as well, so you can take a look in the morning when the lights first come on and you'll see the same thing. Something that looks quite dead, but isn't. If they're healthy, just give it a minute and they'll start to slowly emerge.
As far as environmental conditions go, in general clove polyps can tolerate a broad range of lighting. There are numerous varieties that hail from different environments, but they'll all do fine in aquariums lit by anything considered coral-worthy, from V.H.O. fluorescents to metal-halide systems. So, you don't have to worry too much about where they'll go with respect to lighting requirements. But, if you want them to really thrive they'll need the most they can get, with moderate to bright illumination being the way to go unless you see signs that they may be over-illuminated, such as a failure to open up.
Currents should be moderate. If they are too low, detritus/sediment can accumulate on a colony's base/stolons, so the current needs to be at least strong enough to keep them cleared off fairly well. Conversely, if the current is too strong the polyps will tend to stay retracted to avoid be overly blasted. So, a good turbulent current that stirs the water around a colony is best.
Unlike many other corals, clove polyps aren't going to take any foods you may try to give them. Even fine, plankton-type foods and powders are unlikely to provide any sort of benefit. But, they'll be fine despite this, as long as the lighting is acceptable, so feeding them is one thing you don't have to worry about.
You don't have to fret too much when it comes to where to put a colony with regards to fighting, either. They're highly resistant to the stings of most corals so they'll likely be just fine in crowded conditions. They won't sting anything they touch either, with the possible exception of zoanthid polyps (reported in Sprung & Delbeek, 1997). However, they can simply overgrow other low-lying neighbors, so you'll probably need to pay more attention to other nearby specimens rather than the clove polyps themselves.
Yet another plus is that they can be reproduced/propagated very easily using either of two basic methods. The easiest thing to do is position a small piece of shell or rock right up against part of a colony and let it do the rest. Over time the colony will spread onto this piece of substrate, which can then be cut away from the rest of the colony and moved elsewhere. Just use a razor blade to do the severing and put the newly produced little colony in a suitable spot, or even in another aquarium.
Likewise, if you don't feel like waiting for part of a colony to overgrow something, you can use a razor to cut away a part of the colony and then attach it to a piece of substrate yourself. You can dab the "cutting" on a piece of paper towel to get most of the water off, then use some gel-type "superglue" to attach it to a suitable piece of rock or shell, etc. This is much faster, but takes a little more skill and technique, so I suggest you do some homework specifically on the propagation of soft corals prior to trying it. Once you get the hang of it, it is very easy to do over and over, though.
(CONT)
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