Vermilion star • Mediaster aequalis
{aequalis = equal, a reference to the five evenly-shaped arms}
Photo by Jenn Burt
Identification
The vermilion star has five rays and is usually a beautiful vermilion colour on top (occasionally more orange) and a lighter orange beneath. It gets to 20 cm across.
Habitat & Range
This sea star is found in a variety of habitats - often rocky areas - from the low intertidal to a depth of 500 m. Its range extends from northern Alaska to northern Mexico.
Similar Species
The gunpower star (Gephyreaster swifti) and Pseudarchaster alascensis are similar in shape but a paler reddish-orange colour. The gunpowder star gets to 42 cm across, and P. alascensis has narrower arms and a smaller central disc. Further identification details that can help distinguish the vermilion star can be found on the E-Flora species page.
Intriguing Info
The vermilion star feeds on bryozoans, sponges, and sea pens, as well as detritus. Its diet varies with habitat and season.
iNaturalist
https://www.inaturalist.org/taxa/293174-Mediaster-aequalis
The vermilion star has five rays and is usually a beautiful vermilion colour on top (occasionally more orange) and a lighter orange beneath. It gets to 20 cm across.
Habitat & Range
This sea star is found in a variety of habitats - often rocky areas - from the low intertidal to a depth of 500 m. Its range extends from northern Alaska to northern Mexico.
Similar Species
The gunpower star (Gephyreaster swifti) and Pseudarchaster alascensis are similar in shape but a paler reddish-orange colour. The gunpowder star gets to 42 cm across, and P. alascensis has narrower arms and a smaller central disc. Further identification details that can help distinguish the vermilion star can be found on the E-Flora species page.
Intriguing Info
The vermilion star feeds on bryozoans, sponges, and sea pens, as well as detritus. Its diet varies with habitat and season.
iNaturalist
https://www.inaturalist.org/taxa/293174-Mediaster-aequalis
References
Cowles, D. (2005). Mediaster aequalis Stimpson, 1857. Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed 06/02/2014.
Harbo, R. M. (2011). Whelks to whales: Coastal marine life of the Pacific Northwest [revised]. Madeira Park, BC: Harbour Publishing. P. 172.
Lamb, A., and Hanby, B. (2005). Marine Life of the Pacific Northwest [electronic version]. Madeira Park, BC: Harbour Publishing.
Lambert, P. Mediaster aequalis Stimpson, 1857. ] In Klinkenberg, Brian. (Ed.) E-Fauna BC: Electronic Atlas of the Fauna of British Columbia. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. Accessed 06/02/2015.
Authors and editors of page
Kelly Fretwell and Brian Starzomski (2015).
Cowles, D. (2005). Mediaster aequalis Stimpson, 1857. Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed 06/02/2014.
Harbo, R. M. (2011). Whelks to whales: Coastal marine life of the Pacific Northwest [revised]. Madeira Park, BC: Harbour Publishing. P. 172.
Lamb, A., and Hanby, B. (2005). Marine Life of the Pacific Northwest [electronic version]. Madeira Park, BC: Harbour Publishing.
Lambert, P. Mediaster aequalis Stimpson, 1857. ] In Klinkenberg, Brian. (Ed.) E-Fauna BC: Electronic Atlas of the Fauna of British Columbia. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. Accessed 06/02/2015.
Authors and editors of page
Kelly Fretwell and Brian Starzomski (2015).
