Astropecten polyacanthus is a type of starfish. We also call it the Sand Sifting Starfish or Comb Sea Star. It belongs to the Astropectinidae family. It’s the most common type in the Astropecten genus.
You can find Astropecten polyacanthus starfish in many places. It lives in the Indo-Pacific region. Its arms can spread up to 20 cm, or 8 inches.
Astropecten polyacanthus’s name comes from Latin. ‘Polyacanthus’ means ‘many thorned’.
What Does Astropecten polyacanthus Look Like?
The top of Astropecten polyacanthus is a dark, purple color. The bottom is orange.
On top, you can see little pillars. These pillars have flat tops. They can be cream, gray, or brown in color. Sometimes, these pillars form a pattern that looks like a chevron.
Astropecten polyacanthus starfish has five arms. On the edges of the arms, there are long, sharp spines.
These spines usually have brown bases and pale tips. The arms are quite wide. They can grow up to 9 centimeters or 3.5 inches long.
The feet of the Astropecten polyacanthus starfish are pointed. They don’t have suckers. This helps the starfish to dig into the sand.
How Is Astropecten polyacanthus Different from Archaster Spp.?
Astropecten polyacanthus can be confused with Archaster spp. They look similar because they have both developed features to help them dig through sand. But there are differences.
Archaster has flat, blunt spines. On its top, there are parallel, radial rows of plates. Astropecten polyacanthus doesn’t have these features.
Where Can You Find Astropecten polyacanthus?
Astropecten polyacanthus lives in warm, shallow seas. You can find it in the Indo-Pacific region.
This includes places from the Red Sea and Zanzibar to Hawaii, and from Japan to Australia and New Zealand.
In Australia, you can find Astropecten polyacanthus from Cape Naturaliste in the west to Sydney in the east.
Astropecten polyacanthus starfish likes to live on sandy bottoms in harbors and estuaries. It can live as deep as 185 meters or 607 feet under the sea.
What Does Astropecten polyacanthus Eat?
Astropecten polyacanthus spends a lot of time buried in the seabed. It eats things like detritus and molluscs.
Molluscs are animals with shells, like clams and snails. The Astropecten polyacanthus can swallow these animals whole. It also eats pebbles.
Astropecten polyacanthus digests the biofilm and small animals stuck on the pebbles.
What Should You Know About Astropecten polyacanthus and Tetrodotoxin?
Astropecten polyacanthus has a strong neurotoxin, tetrodotoxin, also known as TTX. This toxin is very dangerous. There is no cure for it.
In Japan, a case of poisoning happened when a person ate a trumpet shell. The shell had eaten an Astropecten polyacanthus and got the toxin from it.
After this, a study was done. It found that most of the 54 Astropecten polyacanthus tested had TTX. One starfish had a toxicity score of 520 mouse units per gram.
Can You Keep Astropecten polyacanthus in An Aquarium?
Yes, you can keep Astropecten polyacanthus in a reef aquarium. It’s good at cleaning up detritus and uneaten food from the sand or gravel in the tank.
Astropecten polyacanthus starfish is mostly active at night. You need to help it get used to the tank slowly. If there are too many starfish in the tank, they will not have enough food and will starve.
Astropecten polyacanthus Characteristics
| Reef Safe? | Yes |
| Care Level: | Easy |
| Maximum Size: | 20 cm (7.9 in) |
Scientific Classification
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Asteroidea |
| Order: | Paxillosida |
| Family: | Astropectinidae |
| Genus: | Astropecten |
| Scientific Name: | Astropecten polyacanthus |
| Also Known As: | Sand Sifting Starfish, Comb Sea Star |
| Conservation Status: | Unknown |