Coral skeletal anomalies resulting from abnormal development of skeleton and associated tissue. Deposition of exoskeleton is altered and morphological features differ markedly from those of the surrounding skeleton and tissue in shape, presence of polyps, size of tissue and skeletal elements, color of tissue, and rate of growth. Can develop on any region of the colony, lesions expand outward and may coalesce. Up to 20-cm in diameter.

1. Enlarged structural elements (A-C, K), also referred to as gigantism, area of accelerated growth, hyperplasm. Focal or multifocal circular to irregularly shaped lesion; abnormally arranged skeletal elements (calices, ridges, valleys), which are larger or smaller than those of the adjacent colony surface. Intact normal-appearing tissue, similar in coloration to adjacent tissue. Often protrudes above the surface of adjacent tissue
2. Loss of normal structural elements (D-H) also called tumor, neoplasm, calicoblastic epithelioma. Focal or multifocal circular to irregularly shaped protuberant lesion consisting of coenosteal skeleton development between and over normal calices, with corresponding loss of polyps. Usually covered by intact tissue lacking zooxanthellae “Bubbling” of tissue may occur at margin of lesion.
3. Chaotic polyp development (H-J) Focal or multifocal spherical to irregularly shaped protuberant lesion consisting of abnormally arranged calices and coenosteum. Usually covered by intact normal-appearing tissue, similar in coloration (sometimes lighter or darker, but zooxanthellae present) to adjacent tissue.