Seven millimeters, which is small enough that a single crinoid is a landscape.
A feather star carries a whole household, and the tenants divide it up by position. Some live out on the feeding arms, colored to match whichever ray they sit on. Some stay down among the cirri, the short curling legs that grip the rock. Some occupy the central disc. Shrimp, squat lobsters, tiny crabs, clingfish and worms, on one animal the size of a dinner plate, and most of them will die if separated from it.
The host matters more than the reef does. These commensals match their particular crinoid's color, follow it when it walks - crinoids do walk, slowly, on their cirri - and follow its schedule, which on most species means folding up by day and opening into the current at night.
This one is among the smallest of them, seven millimeters of dark shrimp with pale stripes, deep in among the arms rather than out where a camera can reach. Finding one means looking into a crinoid rather than at it.
- seven millimeters, dark with pale stripes matching the host's arms
- deep among the arms rather than out on them
- up to 0.7 cm
