Fragile Rainbow Star

Astrometis sertulifera

Astrometis sertulifera, commonly known as the Fragile Rainbow Star, is a distinctive sea star characterized by its brilliant coloration. The spines on its upper surface can display shades of purple, orange, or blue with red tips, while its tube feet often exhibit multiple colors. This species typically has five symmetric arms and can grow to a size of 8.1 cm. It is primarily found in the Eastern Pacific, ranging from Santa Barbara to the Gulf of California, inhabiting rocky bottoms in the low intertidal zone and extending down to depths of 40 meters. The Fragile Rainbow Star has a unique feeding method compared to other sea stars. Instead of using its tube feet to grasp prey from below, it captures small crabs and other invertebrates using specialized appendages called pedicellariae. These parrot-beak-like structures are located around the larger spines on the star's top surface. When prey is detected, the cushion surrounding the pedicellariae raises, and the jaws clamp shut, immobilizing the prey before it is consumed. In terms of reproduction, members of the class Asteroidea, which includes the Fragile Rainbow Star, can reproduce both sexually and asexually. The species can regenerate lost arms, although it is less prone to limb loss than many other California sea stars. Encounters with this species during dives can be interesting, as divers may observe its colors and unique feeding behavior. The conservation status of the Fragile Rainbow Star has not been evaluated.