E-Fauna BC Home

Crossaster papposus (Linnaeus, 1767)
Rose Star
Family: Solasteridae

Photograph

© Neil McDaniel     (Photo ID #15872)

Map

E-Fauna BC Static Map

Distribution of Crossaster papposus in British Columbia in British Columbia

Introduction


Family Description:

Broad disc with five or more long arms. The aboral skeleton is meshlike; the plates bear pseudopaxillae. The marginal pseudopaxillae are larger than the aborals. Oral intermediates are present. The adambulacral spines consist of two series at right angles to each other. The mouth plates are prominent. No pedicellariae.

Illustration

Click on the image below to view an expanded illustration for this taxon. If more than one illustration is available for a species (e.g., two subspecies may be illustrated) then links to the separate images will be provided below.



Species Information

Crossaster papposus is a colourful sea star with 8 to 16 arms, usually 10 or 11, up to 8.5 cm long. Its colour is varies greatly: it may be solid purple or red, but it usually has a concentric pattern of bright red, orange, white or yellow on its spiny aboral surface. The ratio of arm to disc ranges from 1.8 to 2.7. The aboral pseudopaxillae are widely spaced and bear up to 50 slender spinelets. The marginals consist of a single series of prominent pseudopaxillae. The oral interradial area has up to about 25 pseudopaxillae. The adambulacrals usually have 3 to 5 furrow spinelets with a transverse comb of 5 to 9 slightly longer stouter spinelets on the oral surface. The mouth plates have 8 to 10 marginal spines with 2 to 4 suborals.

Characteristics



Similar Species

Crossaster papposus might be mistaken for a juvenile Pycnopodia helianthoides. But P. helianthoides is generally much larger, has more arms, differs in the detail of the aboral surface, adambulacral and mouth-plate spines and ha

Biology


In British Columbia, Crossaster papposus eats the sea pen Ptilosarcus, sea slugs (opisthobranchs), bryozoa, sea squirts and bivalves. It may also attack other sea stars (such as Evasterias troschelli). In Scotland, C. papposus breeds from March to April; each sea star may spawn several times at intervals of two to ten days, shedding more than 2000 eggs at a time, 6000 altogether. The eggs (0.8 mm) are reddish-brown to clay colour and are fertilized externally. The lecithotrophic larva settles to the bottom after 18 days and attaches by a sucker. The mouth forms after about 38 days. Juveniles are often found among the tubes of the polychaete worm Phyllochaetopterus. C. papposus moves at a rate of 60 to 70 cm per minute. A well-fed Rose Star grew from 40 mm to 90 mm in one year. Richard Carlson at the Auke Bay Lab near Juneau studied a population for 17 years. He found that growth rates were quite slow, with individuals achieving a maximum diameter of 30 ern in about 10 years. Their principal prey item was the scallop Chlamys rubida. Crossaster papposus can live for at least 20 years. Mortality rates were low and recruitment of young was infrequent in that population. The scale worm Arctonoe vittata is commensal on C. papposus.

Distribution

Distribution

Circumpolar. In the Pacific, to Washington and the Sea of Okhotsk; in the Atlantic, to 40°N latitude on the American side, and to Scandinavia and the British Isles on the northern European coast. Found from the intertidal zone to 1200 metres deep on soft mud, gravel, sand, pebbles or rock. Common in this region (the area from Glacier Bay to Puget Sound to a depth to 200 metres).

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
UnlistedUnlistedUnlistedUnlisted



BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Synonyms and Alternate Names

Asterias papposa Linnaeus
Solaster papposus (Linnaeus)

Additional Range and Status Information Links

General References