Wormosseum
The Wormosseum has developed a more organized colonial structure to compete with other reef building species and has out-competed its ancestor in its range. Wormosseum reefs consist of many polyps growing off of other living and dead polyps. Mature reefs contain many layers of polyps arranged in concentric rings, the spaces between each ring being home to their juveniles. Adults only have thorns on their most anterior and posterior segments, specializing the anterior for photosynthesis as large plates, and the posterior to form a protective basket for their eggs, or a hold-fast structure to attach to other polyps. The polyps will secrete endoskeletons composed of calcite to keep them rigid and provide the reef with structure. Individual polyps growing over and onto one another will grow these skeletons into one another's bodies, allowing the reef to create an interconnected skeleton that is far more stable than the mounds of their ancestor. The reef can accumulate detritus inside the structure as well as unicellular organisms forming mats on their surface, which can have negative effects on the health of the reef. Reef Ribbons provide this essential cleaning service, clearing the reef of unicellular growths on the polyps and any debris, detritus or waste the juveniles don’t already consume.
The life cycle of the Wormosseum starts with the production of their eggs, which are held externally between the tail thorns of adults. These form an open slit in which sperm produced by other members of the colony may swim to the eggs to fertilize them. The eggs will hatch within a week of conception and hatch into juveniles. The juveniles will live inside the reef, growing quickly as they are fueled by the secretions the adults produce as a byproduct of their photosynthesis. Within a month they have grown to 4 cm in length and are ready to transition into their adult polyp stage. Their eventual body form and where they will become adults depends on various factors. Growing reefs tend to have their juveniles transition into adulthood inside the reef and add to the reef's size, whereas full sized reefs tend towards juveniles venturing outside their home reefs to join other growing reefs or found their own.
When founding a new reef, juveniles will congregate with anywhere from 5-20 other juveniles in an open area of substrate where they can transition. They will arrange themselves radially with their posterior ends in as close contact as allowable, and then transition into their J-shaped adult forms. This results in two circles of stalks: the inner shorter and denser packed than the outer, and an interior section free of the adult polyps. From this point the newly founded reef will begin reproducing and attracting wandering juveniles. As new members transition into their adult polyp forms, they will fill out the reef and build the structure upward. New layers of polyps will form as the reef grows, resulting in many consecutive rings of polyps with spaces between them for the juveniles and Reef Ribbons to inhabit. Eventually the reef can reach 2 meters wide, with many layers of polyps forming the walls of the reef.