---
title: Comb Sea Star (Astropecten polyacanthus)
scientific_name: Astropecten polyacanthus
common_name: Comb Sea Star
taxon: Starfish
published: 2026-08-06T16:37:23.113Z
updated: 2026-08-20T17:09:46.102Z
tags: Comb Sea Star, Astropecten polyacanthus, Starfish, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/invertebrate/echinoderms/starfish/comb-sea-star
---

# Comb Sea Star (*Astropecten polyacanthus*)

## Quick facts

- **Group:** Starfish (*Asteroidea*)
- **Size:** up to 20 cm
- **Depth:** 0-40 m
- **Diet:** Carnivore
- **Activity:** Nocturnal
- **Rarity:** Common
- **Habitat:** Open sand flats, often buried
- **Reproduction:** Broadcast spawner, Gonochoric
- **Hazard:** Poisonous

## How to recognise it

- flat five-pointed star with straight-edged arms
- white, elongated spines along the arm margins - the identifying character
- sandy gray to beige, matching the bottom
- usually buried by day, leaving a faint star-shaped outline in the sand
- diameter up to 20 cm

A flat, neatly geometric star to about 20 cm (8 in), sandy gray to beige, its straight-edged arms fringed with rows of comb-like marginal spines. Everything about it is built for sand: the flattened profile, the pointed tube feet that have no suckers and work as diggers rather than grippers, and the color that matches whatever bottom it is crossing.

It lives on open sand flats from the shallows to about 40 m (130 ft) and spends most daylight buried, leaving a faint star-shaped outline in the surface that a slow diver learns to spot. Feeding sets it apart from reef stars: instead of everting its stomach onto a surface, it swallows small snails and bivalves whole, digests them internally and ejects the empty shells. Where the sand is rich the animals can be numerous, and a night dive over a flat bottom often turns up a dozen plowing along in the open. It carries tetrodotoxin in its tissues, which deters most predators but poses no risk to a diver who does not eat it.

## Also known as

- **English:** Sand Sifting Sea Star, Brown-spotted Sand Star, Comb Sea Star
- **French:** Étoile piquante
- **Italian:** Stella pettine indo-pacifica
- **Spanish:** Estrella de mar arenera
- **Portuguese:** Estrela-pente-do-Indo-Pacífico
- **Czech:** hvězdice mnohotrnná
- **Japanese:** トゲモミジガイ
- **Chinese:** 多棘槭海星
- **Russian:** Гребенчатая песчаная звезда
- **KO:** 가시불가사리
- **MRI:** Pekapeka
- **TH:** ดาวทรายหนาม

## Scientific synonyms

- *Astropecten chinensis* Grube, 1866
- *Astropecten edwardsi* Verrill, 1867
- *Astropecten ensifer* Grube, 1866
- *Astropecten hystrix* Müller & Troschel, 1842
- *Astropecten samoensis* Perrier, 1869

## Range

Coral Sea, Eastern Africa & Madagascar, Indian Ocean, Kenya, Mozambique, New Caledonian Exclusive Economic Zone, New Zealand, North Pacific Ocean, Persian Gulf, Red Sea, Republic of Mauritius, Seychelles, South Pacific Ocean, Tanzania

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*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/invertebrate/echinoderms/starfish/comb-sea-star)*
*Updated: August 20, 2026*