Heliaster solaris

Heliaster solaris commonly known as 24-rayed sunstar is a possibly extinct sea star which was known from the waters near Española Island in the Galápagos Islands.
Description.
"Heliaster solaris" had 22 to 24 cylindrical and elongated more or less distinctly banded rays which were tapering at the ends. They were one third longer than the diameter of the body. The dorsal rows of the spines were longer and more compressed. The spines, pedicellariae, and the madreporic plate were light yellowish.
Taxonomy.
This species was first mentioned by John Edward Gray in 1840 in the Annals and Magazine of Natural History as "Asterias multiradiata" and later as "Heliaster multiradiatus". Due to the fact that Carl Linnaeus used the name "Asterias multiradiata" (current accepted name: "Capillaster multiradiata") already in 1758 Gray's name became an invalid homonym. In 1920 Austin Hobart Clark published the replacement name "Heliaster solaris".
Extinction.
"Heliaster solaris" disappeared during the El Niño Southern Oscillation event which affected the Galapagos Islands in the early 1980s.