. . "Sandcastle worm"@en . . . . . "The sandcastle worm (Phragmatopoma californica), also called the honeycomb worm or honeycomb tube worm, is a reef-forming marine polychaete worm belonging to the family Sabellarididae. It is dark brown in color with a crown of lavender tentacles and has a length of up to about 7.5 centimeters (3.0 in)."@en . . . .