Leptoseris have been a popular aquarium coral for quite some time now. The orange colonies of ‘Leptos’ were among the first of this color in the reef aquarium hobby, followed by the brilliance of the ‘Jack o Lantern’ Leptoseris, ‘Tangerine Juice’ and their relative low maintenance make them very popular corals. Recently while diving in Indonesia, we came across a very weird and unusual growth form of Leptoseris; It took us a while to be able to identify it and what we found remarkable about this coral is the very unique bicolor speckled coloration.
Description:
As its name indicates, Leptoseris incrustans colony shape is mainly encrusting, but can develop thick short laminae, often harboring radiating ridges. Corallites are very small, closely compacted and superficial. The small corallite is on of the differentiating factor with other colony. Because we couldn’t distinguish the corallites at first glance, and in turbid water, we thought it was some kind of algae or sponge. Septo-costae are thin and equal, giving colonies a smooth surface and since these are not granulated, it is distinctive from Coscinaraea.
Although most colonies we met were pretty flat, they can develop bumps on their ‘coenosteum’ similar to Hydnophora-like monticules.
A nice green polyp colony of L. incrustans, not the monticule like structures in between polyps. 
Colonies are thick and encrusting. 
A close up of the bright green polyps with the classic neat septo-costa grooves.
Habitat:
This particular Leptoseris incrustans favors shallow, highly turbid protected bays which are certainly not really the kind of place we enjoy diving. And even in the right location or habitat Leptoseris incrustans isn’t really uncommon thus making this species even more desirable.
Maintenance:
Please note the thick layer of sediments outside of the colony. 
This coral thrive in high turbidity environment by 35 ft (12 m) deep 
Leptoseris in general are not really demanding. They evolved to adapt to an environment where competition is low. Often deep, turbid, or cryptic habitat, where light is diffused, indirect, and low. And flow is also very weak. Making them really well suited aquarium candidates, as when the competition factor is under control, and light, flow and water quality are above average, they often thrive. Leptoseris corals develop and hold color really well, and grow very fast under aquarium condition, making them perfect propagation candidates too.
Coloration:
Like many Leptoseris, L. incrustans is available in a wide range of colors, we’ve seen it green, orange, pink and red. But the most interesting feature was the speckled surface.
We haven’t tried to keep that species on the long run, to know exactly how it holds it’s remarkable speckled coloration in an aquarium but if it does, Leptoseris incrustans could really become a holy grail for this group of low light, encrusting corals.
