Acropora lutkeni
Crossland, 1952
Description: Colonies are corymbose plates with thick tapering branches. Branches have incipient axial corallites and branchlets developing towards their base. Sometimes branches are long. Axial corallites are rounded and not much larger than radial corallites. Radial corallites are irregular and have a wide range of shapes and sizes but are characteristically thick walled with rounded margins.
Color: Uniform grey, creamy brown, or purple.
Habitat: Shallow upper reef slopes exposed to strong wave action or currents.
Abundance: Sometimes common on the Great Barrier Reef, usually uncommon elsewhere.
Similar Species: Acropora polystoma, which has similar growth-forms and irregular corallites, but corallites are sharp edged, not rounded. See also A. austera, A. forskali, which has twisted branches and A. seriata, which has hhighly fused branches.
Source reference: Veron (2000). Taxonomic references: Crossland (1952), Veron and Wallace (1984), Wallace (1999). Identification guide: Veron (1986).
Acropora lutkeni (left) adjacent to A. abrotanoides (right) forming branches. Dampier Archipelago, Western Australia Photograph: Charlie Veron
Skeletal detail. Axial and radial corallites.
On an upper reef slope, showing the common appearance of corallites. Great Barrier Reef, Australia Photograph: Charlie Veron