Iconaster longimanus

(Mobius, 1859)

Icon Star

Range: Indo-West Pacific Ocean

Natural Environment: Inhabits deep reef areas where rubble collects.

General Husbandry: This is a beautiful sea star with five thin, flattened arms. Its marginal plate areas usually have large random light tan and dark brown plates, which surround smaller central disk plates of burnt orange. Colors may vary slightly depending upon area of origin.

Even thought rarely seen in the trade, they appear to be reef safe and good scavengers of detritus, microalgae, small benthic invertebrates and other organic matter.

Since this sea star comes from areas receiving little light, it should be maintained in aquariums containing sufficient hiding places, i.e., with lots of live rock. And since its central disc can attain a diameter of about 4 inches (10 cm), would consider a 100 gallon aquarium the smallest it should be kept in.

Keep in mind they are toothless, and either swallow their prey whole, then expel the undigested parts (such as hard shells) or extend their stomach and digest whatever they are resting upon, such as what the Crown-of-Thorns does to coral polyps.

As for feeding, there probably isn't a hobbyist aquarium that can naturally provide this creature its necessary nutritional needs long term. Therefore, suggest placing different type and size meaty foodstuffs on the aquarium substrate just prior to the lights going out. These creatures, if healthy, are very capable of knowing when food enters the aquarium and will usually quickly take the shortest path to the foodstuff.

Again, the long-term success rate with this sea star appears to be dismal at best. And keep in mind, all starfish are very vulnerable to sudden salinity/specific gravity changes. (Salinity is the correct term for measuring a natural salt level in the wild, and specific gravity is the correct term for artificially prepared seawater.) Therefore, acclimate carefully before transferring new purchases to your aquarium.

Taxonomy:

Kingdom: Animalia

Phylum: Echinodermata

Class: Asteroidea

Order: Valvatida

Family: Goniasteridae

Genus: Iconaster

FYI: Long-term success rate with this sea star appears to be dismal at best. And keep in mind; all starfish are very vulnerable to sudden salinity/specific gravity changes. (Salinity is the correct term for measuring a natural salt level in the wild, and specific gravity is the correct term for artificially prepared seawater.) Therefore, acclimate carefully before transferring new purchases to your aquarium.

Experience Level: Expert

Diet: Omnivore

Aquarium Environment: Reef or fish-only aquarium

Coral Safe: Yes

Fish Safe: Yes

Invertebrate Safe: Yes

Acclimation Time: Sensitive to specific gravity/salinity changes, therefore be sure to adjust the bag's water to that of the aquarium in which it will be placed by slowly adding small amounts of aquarium water to the bag every few minutes. In most cases, this process should take at least 15 minutes.

Aquarium Hardiness: Moderate to difficult

Temperature Range: 72 - 83°F (22 - 28°C)

Minimum Tank Size: 100 gallons

Specific Gravity: 1.023 - 1.025

pH: 8.0 - 8.4