Preview
Family
Anthothelidae
Common Name(s)
Deep-water sea fan, Black sea fan
Colony Form
Monoplanar stiff fan with dichotomous branches not interconnected; to ~1 m tall.
Axis
Flattened in plane of fan.
Branches
Flattened in plane of fan, dichotomous, not interconnected, 3-5 mm across. Secondary branches and unbranched twigs usually bent. Terminal twigs along fan periphery usually forked. Edges of twig ends folded over and joined so that twig tips are indented or grooved (=fistulose).
Apertures
Polyps restricted to sides of branches. Calices are low oval or slitlike mounds with eight lobes.
Mucus
None
Color
Red-brown, copper, dark brown or grey. Often appearing black in situ. Usually light brown when dried.
Sclerites
Polyp armature: flattened, slightly curved spindles to 0.5 mm long, arranged in eight series of inverted V’s (“en chevron”). Outer layer: chiefly elongate spindles 0.5–0.6 mm long, with ornamentation ranging from scattered small thorns to crowded tubercles. Inner layer: smooth to slightly warty, extremely slender needles 0.5–0.7 mm long.
Habitat
Deeper reefs, commonly along slopes, walls, crevices and canyons exposed to currents. Depth range: 3-368 m, usually below ~15 m.
Distribution
Georgia to Brazil, Bahamas, Caribbean Sea.
Similar Species
Date Taken
4-11-2016
Notes
Unlike sea fans of genus Gorgonia, I. schrammi branchlets do not interconnect. Fans vibrate in strong currents. The indented or grooved twig tips are unique among shallow, Western Atlantic octocorals.