Acropora aculeus
(Dana, 1846)
Description: Colonies are corymbose clumps. Horizontal branches are thin and spreading. Upward-projecting branchlets are fine. Axial and radial corallites are not clearly differentiated at branchlet tips. Radial corallites on branch sides are nariform, with slightly flaring lips.
Color: Usually grey or bright blue-green or yellow. Tips of branches may be yellow, lime green, pale blue or brown.
Habitat: Upper reef slopes and lagoons.
Abundance: Usually common in the central Indo-Pacific, uncommon elsewhere.
Similar Species: Acropora elegantula. See also species forming irregular corymbose plates, especially A. latistella and A. subulata. These species are readily differentiated by colony shape, clearly formed axial corallites, and tubular and appressed radial corallites.
Source reference:
A large colony. Papua New Guinea Photograph: Charlie Veron
Colony surface. Great Barrier Reef, Photograph: Charlie Veron
Colonies are commonly cushion-like, with slightly diverging branches and compact branchlets. Papua New Guinea Photograph: Charlie Veron
Colony surface. Papua New Guinea Photograph: Charlie Veron
Corallite detail. Tentacles are commonly extended during the day. Great Barrier Reef, Australia Photograph: Roger Steene
Skeletal detail. Radial corallites.