Purple Hydrocoral

Stylantheca porphyra/Stylantheca papillosa

Purple Hydrocoral

Stylantheca porphyra/Stylantheca papillosa
Other Common Names
Purple encrusting hydrocoral, corrugated lace hydrocoral
Other Common Names
Purple encrusting hydrocoral, corrugated lace hydrocoral

At the Aquarium

Rocky Coast

Appearance

This colonial animal has a bright purple calcium carbonate skeleton with many pinpoint-sized pores. Small polyps extend from these pores: gastrozooids for feeding are surrounded by a ring of stinging defense structures called dactylozoids. In shallower water it typically grows as an encrusting mat that can reach a diameter of 11.8 inches, but in deeper, calmer water, knobby branches can grow upright from the mat and reach to 0.8 inches tall.

Habitat

Encrusts rock from the rocky intertidal to depths of 89 feet in current-swept areas.

Diet

This animal catches tiny bits of food from the water.

Life History

The colony is either a male or female colony. Males release sperm through a duct and it will then enter a female colony. Females brood fertilized eggs and release an advanced planulae, about 0.08 inches long, through a canal. The larval stage only lasts 3-8 hours, with the larva typically crawling a short distance from its parent before settling.

IUCN Status

Not Evaluated

Ecosystem & Cultural Importance

The predators of purple hydrocoral include the wrinkled star.
Alaska to Central California
Encrusting purple hydrocoral can be found in the low intertidal or subtidally while diving.
There is a worm that will live in purple hydrocoral colonies, forming a tube with distinctive paired holes at the surface. Extending from one of these holes may be 2 tentaculate palps, the worm’s appendages used for feeding, and these search all around the outside of its tube for food. When a small particle is encountered, each tentaculate palp has a food groove that uses cilia to move food particles to the worm’s mouth.

Citations & Other Resources

  • Brooke, Sandra, and Robert Stone. inchesReproduction of deep-water hydrocorals (family Stylasteridae) from the Aleutian Islands, Alaska.inches Bulletin of Marine Science 81.3 (2007): 519-532.
  • Cairns, Stephen D. inchesGlobal diversity of the stylasteridae (Cnidaria: Hydrozoa: Athecatae).inches PloS one 6.7 (2011): e21670.
  • Etnoyer, Peter, and Lance Morgan. inches Occurrences of habitat-forming deep sea corals in the Northeast Pacific Ocean.inches NOAA Office Habitat Protection, Silver Spring, MD (2003).
  • Global Biotic Interactions website
  • Hoeke, Jackson Tyler. Native and Introduced Hydroids (CNIDARIA: HYDROZOA) from the Marine Waters of Coos County, Oregon. Diss. University of Oregon, 2020.
  • The Natural History of Bodega Head website
  • The Natural History of Bodega Head website