''Leptasterias aequalis'',
common name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...
s little six-rayed seastar or six-armed star, is a species of brooding
starfish
Starfish or sea stars are Star polygon, star-shaped echinoderms belonging to the class (biology), class Asteroidea (). Common usage frequently finds these names being also applied to brittle star, ophiuroids, which are correctly referred to ...
.
This is a small species, with a total width of only about . The coloration is extremely variable.
This seastar is found in the northeastern
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...
, from
Washington
Washington most commonly refers to:
* George Washington (1732–1799), the first president of the United States
* Washington (state), a state in the Pacific Northwest of the United States
* Washington, D.C., the capital of the United States
** A ...
to
Southern California
Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural List of regions of California, region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal reg ...
. It lives on rocky shores, in the mid-
intertidal zone
The intertidal zone or foreshore is the area above water level at low tide and underwater at high tide; in other words, it is the part of the littoral zone within the tidal range. This area can include several types of habitats with various ...
.
Many sea-stars broadcast-spawn their embryos, where fertilization occurs in the water column; however, Leptasterias species brood their embryos locally. The stars form mating aggregations and the female sits on her brood for a period of 6–8 weeks while the embryos develop underneath. Eventually, the embryos fully metamorphose into juvenile sea-stars and walk away, and thus can only locally disperse. Larger females produce larger embryos of great quality; however, as larger broods are produced, a considerable proportion of them are lost.
References
External links
* Much good information at
* CalPhoto image 1
* CalPhoto image 2
Leptasterias, aequalis
Echinoderms described in 1862
{{Asteroidea-stub