Description: This sponge can be stalked or branching-erect. Usually dichotomous, the branches are simple or coalescent and cylindrical in cross- section. Many-branched forms seem to be typical of estuarine or strong current conditions. Under extreme conditions it may have a fist-shaped form. Usually pale yellow or beige, but lilac or pink forms have been reported, with new growth tending to be pinker. It is very soft and elastic near the branch tips, becoming firmer near the base. The base may, in older specimens, be very firm and elastic. Unlike many other branched sponges, there is no strong central core to the branches. The surface is evenly textured, soft, and very slightly velvety. The numerous neat oscules are small (0.5 - 2mm diameter), round, slightly raised, and remain easily visible even when the sponge is removed from the water. Usually serially arranged along the edges of the branches.

Habitat: In sheltered but fast-moving water, rapids, estuaries, straits, where it can tolerate high levels of siltation. Also on vertical rockfaces in exposed open-coast conditions, where it usually forms single stick-like, unbranched colonies, or sparsely branched colonies.

Distribution: "Arctic; British Isles", including North Sea coasts; "Atlantic coasts of Europe south to the Channel; etc." Known recently from the Menai straits, many channel coast locations, entrances to sea lochs in Scotland and Ireland, and offshore rocky sites.

Similar Species: May be identified by eye alone, if very soft and elastic, with branches that are even in diameter with neat, round, easily visible oscules. The absence of a strong central core distinguishes Haliclona oculata from Raspailia and Stelligera.

Key Identification Features:

• Very soft and elastic near branch tips.
• No strong central core to branches.
• Numerous neat oscules usually serially arranged along edges of branches.

Distribution Map from NBN: Haliclona oculata at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Haliclona oculata at iNaturalist World Species Observations database.

GBIF data for Haliclona (Haliclona) oculata

WoRMS: Haliclona oculata at World Register of Marine Species. Accepted name: Haliclona (Haliclona) oculata (Linnaeus, 1759). AphiaID: 132833.

Classification: Biota; Animalia; Porifera; Demospongiae; Heteroscleromorpha; Haplosclerida; Chalinidae; Haliclona