The southern gildring split from its ancestor, the gildring, though replacing it in the southern sections of Mason Polar Beach. Like its ancestor, it grows in round, flat colonies that continually grow outward. Its photosynthesizing "leaves" are wide enough to enclose the insides of the colony, the top enclosing water that fills the colony between cells, heated by the sun. Scattered at uneven intervals between the cells, hitchhiker nitroids and their decedents are cultured to provide fixed nitrogen for the colony. Its ring shaped is cause by its method of reproductive methods. As the cells near the center of the colony use up the available nutrients in the soil, they will release their grip on the soil and float away, starting new colonies elsewhere. This gives them a unique ring shape, such as that shown in the older individual in the picture. While individual cells are microscopic, colonies can grow meters wide.