---
title: Barrel Sponge (Xestospongia testudinaria)
scientific_name: Xestospongia testudinaria
common_name: Barrel Sponge
taxon: Sponge
published: 2025-01-24T19:49:41.523Z
updated: 2026-08-12T23:04:29.797Z
tags: Barrel Sponge, Xestospongia testudinaria, Sponge, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/invertebrate/sponge/barrel-sponge
---

# Barrel Sponge (*Xestospongia testudinaria*)

## Quick facts

- **Group:** Sponge (*Porifera*)
- **Size:** up to 1.5 m across
- **Depth:** 5-60 m
- **Diet:** Filter feeder
- **Activity:** Cathemeral
- **Rarity:** Common
- **Habitat:** Reef slopes and walls with current
- **Reproduction:** Broadcast spawner, Budding, Gonochoric

## How to recognise it

- large barrel or vase with a wide open top, brown to red-brown
- surface ridged and grooved into a rough network, hard and brittle to touch
- usually standing alone on a slope, sometimes with a fish sheltering inside
- up to 1.5 m across

A barrel of an animal, up to 1.5 m (5 ft) across, brown and ridged, standing open-topped on a reef slope. It is hard and brittle rather than soft, and it is one of the few animals on a reef that a diver will mistake for furniture.

It is a pump. Water is drawn in through millions of pores across the surface by beating flagella, stripped of bacteria and organic particles, and pushed out of the opening at the top - and a large sponge processes many times its own volume every hour, thousands of liters in a day. On a reef with enough of them, the whole water column is filtered repeatedly.

Most of what it eats is too small to see. Sponges of this family live on bacteria and dissolved organic matter and then release the carbon they capture as a rain of shed cells, which other animals eat - the sponge loop, a pathway that only got its name in 2013 and turned out to be one of the main ways a reef recycles what would otherwise be lost.

They grow slowly and live for centuries; large individuals on Caribbean reefs have been aged at over two thousand years, which makes the barrel sponge one of the oldest living things a diver will ever swim past.

## Also known as

- **English:** barrel sponge, Indo-Pacific Giant Barrel Sponge, large barrel sponge, turtleshell bath sponge
- **French:** Éponge-barrique
- **Italian:** Spugna barile gigante
- **German:** Badewannenschwamm, Großer Vasenschwamm
- **Spanish:** Esponja gigante de barril
- **TH:** ฟองน้ำครก

## Scientific synonyms

- *Alcyonium testudinarium* Lamarck, 1815
- *Petrosia testudinaria* (Lamarck, 1815)
- *Petrosia testudinaria var. fistulophora* Wilson, 1925
- *Reniera crateriformis* Carter, 1882
- *Reniera testudinaria* (Lamarck, 1815)
- *Xestospongia testudinaria var. fistulophora* (Wilson, 1925)

## Range

Andaman Sea Coral Coast, Andaman and Nicobar Islands, Andaman and Nicobar Islands Exclusive Economic Zone, Arafura Sea, Banda Sea, Central and Southern Great Barrier Reef, Eastern Philippines, Exmouth to Broome, Gulf of Thailand, Gulf of Tonkin, India, Kenya, Malacca Strait, New Caledonia, Singapore, South China Sea Oceanic Islands, Southern Vietnam

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*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/invertebrate/sponge/barrel-sponge)*
*Updated: August 12, 2026*