News / Species Spotlight / Blastomussa wellsi (02/17/15)

Blastomussa wellsi


  • Class: Anthozoa
  • Order: Scleractinia
  • Family: Mussidae
  • Genus: Blastomussa
  • Species: wellsi

The Blastomussa wellsi is one of two members of the Blastomussa genus. The other species being Blastomussa merleti, which differs in several ways with the most notable difference being the polyp shape and the size of the corallites. The wellsi polyps can be asymmetrical in shape with corallites ranging in size from 8-15 millimeters in diameter while the merleti species has symmetrical polyps with distinctly smaller corallites, measuring 6-8 mm. The wellsi is commonly collected in a larger variety of colors than the merleti and as such is typically regarded as being more desirable to aquarists. The polyps come in a myriad of colors including red, pink, green, purple, yellow, and occasionally blue. The species can be monochromatic, having only one color; but are most often seen with a combination of two or more colors.

Natural Habitat:

The Blastomussa wellsi are commonly found on lower reef slopes protected from wave action and turbid environments (Veron). They inhabit waters from the Central Pacific to the Indian Ocean with species occasionally seen in the Red Sea. In recent years the vast majority of Blastomussa wellsi specimens have been collected from the Indian Ocean.

In the wild, Blastomussa have two specific food sources which account for the majority of their nutrition. The first primary food source is derived through the relationship between the polyps of the coral and the zooxanthellae located within the tissue of these polyps. The zooxanthellae are symbiotic algal cells, which use sunlight, carbon dioxide, and nitrogen as a food source. As these products are consumed, they create oxygen and other byproducts through a photosynthetic process. The polyps of the coral use the oxygen and byproducts to produce their own nitrogenous waste and carbon dioxide which then used as a food source for the zooxanthellae, at which point the cycle starts over.

The secondary primary source of food is planktonic matter. Blastomussa are capable of consuming a broad range of sizes of planktonic matter. As the current pushes plankton through the water, the slightly sticky tissue covering the surface of the polyp will catch floating food. The polyps can manipulate their shape in many ways and will push the food towards and into their oral disc which is located directly in the center of each polyp.

Aquarium Suitability:

Members of the Blastomussa family are generally hardy corals, with B. merleti being moderately hardier than B. wellsi. As mentioned before, Blastomussa corals use their zooxanthellae to derive energy from the tank lighting; but both species will experience more rapidly growth if fed a nutritious diet of zooplankton.

The Blastomussa wellsi should be acclimated to light very carefully, as high levels of light can agitate the coral causing the tissue of the polyps to recede. We recommend that all new specimens be placed in a low light area of the tank and gradually move them closer to the light until the desired location is reached. This should allow ample time for the coral to adjust to the increase in light levels and recover from shipping stress. Additionally, the coral is intolerant of high currents, which can also cause recession. Placement in a low to medium flow area will increase the chances of success with the species. Another placement issue is that despite the fact that the wellsi do have nematocyst stinging cells, they are typically less aggressive than many other hard and soft corals. The sting of other corals can be very harmful to the Blastomussa, so care should be taken when placing the coral nearby any aggressive coral species.

An occasional problem with importing Blastomussa is the poor treatment that they often receive along the chain of custody. If not provided with a decent light source, clean water, and a moderate supply of zooplankton at stages during transit, the polyps of the coral may be severely retracted when arriving at stores. To aid in the corals recovery, we recommend that Blastomussa be spot fed for the first week spent in captivity. Foods such as mysid shrimp, gamma shrimp, or brine shrimp fed with selcon are very nutritious and are of ideal size for ingestion. Given the right level of care and consistent feeding, a near fully receded specimen can recover to be in perfect condition within a week or two.


Veron, JEN, 2000 Corals of the World. Vol. 3. Australian Institute of Marine Science. p. 6-7.