Galaxea horrescens
Dana, 1846
Description: Colonies are arborescent. Corallites are tubular and thin walled with flaring rims. Columellae are absent. Septa are very exsert. Tentacles are usually extended only at night. They have tapering translucent tentacles with white tips.
Color: Pale brown, yellow or green, sometimes with white branch ends.
Habitat: Usually found in reef areas with good water circulation and light availability.
Abundance: Uncommon.
Similar Species: Galaxea acrhelia.
Source reference: Veron (2000). Taxonomic reference: Veron and Pichon (1980, as Acrhelia horrescens). Identification guides: Randall and Myers (1983), Veron (1986), Nishihira and Veron (1995), all as Acrhelia horrescens.
Colonies are usually compact in shallow water exposed to wave action. Great Barrier Reef, Australia Photograph: Ed Lovell
With tentacles extended during the day. Flores, Indonesia Photograph: Charlie Veron
A finely branched colony. Papua New Guinea Photograph: Jim Maragos
Skeletal detail. Showing corallites.
Corallites usually have very long sabre-like septa. These may be similar to those of G. longisepta, in which case the species can be distinguished by their distinctive growth-forms. Guam Photograph: Gustav Paulay