Blue Ofwegenum left, next to the new Cladiella, right, with a pale violet Conglomeratusclera between them
By Julian Sprung, June 16, 2026
I can't get enough of brown soft corals. Old-school reef keepers seem to gravitate to this reality. With all the fluorescent fruit salad, splattered and glittery corals being promoted in the online hobby marketplace there is something to be admired in the simpler beauty of luscious brown feathery polyps that can be found abundantly in octocorals such as photosynthetic gorgonians, xeniids, and the many varieties of "leather corals." The family cladiellidae within the latter group includes old standards in the reef aquarium hobby that are now seldom seen in the trade... "Colt corals" in the genus Klyxum and Cladiella were standard features in the early days of reef-keeping, for example. Closely related to those is the blue or blue-green Ofwegenum, which was the indirect subject of my previous blog post about "Sympodium." Less well recognized is the genus Aldersladum, which is sometimes available in the trade as an aquacultured feature coral from Oceans Reefs and Aquariums.
Aldersladum from ORA, bottom right. This coral is sometimes mistakenly referred to as Asterospicularia in the aquarium trade.
The same specimen of Aldersladum with polyps closed.
I am writing this post to share some observations about a beautiful new soft coral that I received from Levi Peterson from Quality Goldfish. When I first received it I could tell by its gross appearance that it belonged to the family cladiellidae, but the genus wasn't obvious. It had features that were a blend of Ofwegenum and Aldersladum, and Levi told me that it had been imported together with the normally blue Ofwegenum (aka "Sympodium") as a brown "Sympodium." That was pretty exciting to me as it seemed it might be a new species and possibly a new genus. I had never seen anything like it before. I sent a sample to soft coral expert Cathy McFadden who confirmed with molecular analysis and a look at the sclerites that this soft coral is without a doubt a species of Cladiella. That was not what I expected! The Cladiella spp. that I know form lobed and branchy colonies, with small brown polyps, and they "blanche" white when the polyps contract if the colony is physically disturbed. This new coral grows compact colonies, with large polyps over small separate sections of short branches, as I said rather similar to Ofwegenum and Aldersladum. It does blanche a bit when the polyps contract, but so does Aldersladum. The lesson for me (and, hopefully for readers of this blog post), is that Looks Can Be Deceiving!
This is an example of a more typical-looking Cladiella sp.
Here is another common Cladiella sp., with longer branches.
In stony corals there is, among others, the example of Cycloseris... it normally forms round, solitary free-living polyps with one or at most a few centrally located mouths. They are obviously what you would describe as a fungiid coral. But DNA analysis shows that a few species also form thin encrusting colonies with many mouths, looking more like a Leptoseris or Lithophyllon. That reality causes pain for old school coral taxonomists who rely on gross as well as minute scale physical characteristics for distinguishing genera. The genus Lithophyllon has a similar "taxonomists be damned" group of species, with "classic" forms being encrusting, undulating, multi-mouthed colonies, but other species are solitary free-living circular fungiids that any old-school taxonomist looking at a photo of one might initially call "Fungia sp." ... but the DNA identifies them as Lithophyllon.
So this Cladiella has DNA and sclerites that don't align with its gross appearance. That's a fact, and it is a cool one. What does it mean?
I remember that when I first met soft coral expert Phil Alderslade in the 1990s when he and I were visiting our mutual friend Alf J. Nilsen in Norway, in conversation while Phil had his head over the microscope looking at the sclerites of some soft corals from Alf's aquarium I may have let slip a hunch I had that sclerites could be misleading if convergence could produce the same forms in related genera, or in unrelated ones... a sort of convergent "mimicry." That thought did not go over too well. At the time taxonomic decisions were made based on minute details of sclerite forms.
The relatively recent exploration of soft coral taxonomy via DNA analysis has in fact confirmed my hunch, even if examples are more exception than rule of course. In conversation with soft coral expert Cathy McFadden, she pointed out that,
"We have plenty of examples of convergent evolution of sclerite form and other morphologies in the octocorals that we've only realized after getting into the DNA. Probably the two most surprising are the jointed axis of 'bamboo' corals and the 'balloon club' sclerites of the gorgonian genus Eunicella. We always assumed each of those unique morphologies had evolved only once, but it turns out that the shallow-water bamboo Isis is in a different order from the deepwater bamboos, and the W. Atlantic Eunicella species (no longer Eunicella!) are in a different family from the E. Atlantic Eunicella. So, convergent evolution of the jointed axis and the balloon clubs. Then we have the opposite case where things that appear to be totally different morphologically are in fact closely related. The family Coralliidae is a great example of that -- the deepsea 'mushroom' coral genus Anthomastus is very closely related to the precious corals (Corallium) and the bubblegum corals (Paragorgia). Totally different growth forms, but it turns out they all share quite similar sclerites."
There are numerous examples of identical or similar physical form (skeletally or in the living polyp form) in scleractinia too, even though there is no close relationship... just chance convergence. But... in the case of this Cladiella, you have both microscopic form and DNA telling the same story while it conflicts with the gross appearance. To use an overused phrase... it is what it is. I find these sorts of taxonomic lessons intriguing and you can be sure I will describe more of them in subsequent blog posts.
The new Cladiella sp. viewed from the side through the (dirty) glass of my aquarium.
Another view of the new
Cladiella sp., viewed from above, showing a section with polyps fully closed.
When the polyps of this new Cladiella sp. are partially closed they look like kernels of popcorn.
