Corals are colonial animals composed of many individual polyps and can be found in the tropics and subtropics. The marine waters around Taiwan support a great number of corals. To introduce the beauty and diversity of the corals of Taiwan to the public, Chunghwa Post is issuing a set of four stamps. The designs follow:
1. Dendronephthyagigantea (NT$3.5): Colonies of this soft coral, which often have a branched growth form, are covered with bunches of red polyps. The coral polyps expand only at night or when the water flow is high. The colony deflates into a ball when the polyps retract. This coral is widely spread through Taiwan's coastal waters in areas that are exposed to strong currents, usually at depths of greater than 15 meters.
2. Pavona cactus (NT$5): Colonies of this stony coral, which are shaped like the flower heads of hydrangea, are made up of thin and contorted upright fronds with thickened bases. There are rows of small shallow corallites parallel to the margins on both sides of the fronds. The coloration of this coral ranges from light brown to greenish brown. It is found in shallow areas where the water is murkier, and in particular on upper reef slopes in northern and northeast Taiwan.
3. Acroporagranulosa (NT$10): Colonies of this stony coral are composed of stubby branches which connect or fuse at the base to form plates. There is a large protruding axial corallite on the tip of each branch. The radial corallites are smaller and tubular in shape. Living colonies are bright pink or reddish brown. The coral can be found on upper reef slopes and reef flats in shallow waters. It is often sighted in the Dongsha Atoll.
4. Melithaeaochracea (NT$15): Colonies of this gorgonian coral are arborescent and have branching structures shaped like fans. The nodes of the main branch and branchlets are conspicuously enlarged. The tiny white or translucent polyps are distributed on the sides and front of the branches. The colonies of this coral are orange red with a lighter colored main skeleton. The bases of the polyps are yellow. The coral inhabits the higher parts of reef fronts in areas with stronger water flow. It can be found in reefs throughout Taiwan's waters.