Colony Form:Tall, plumose, with several long main branches and sometimes with secondary plumes arising from main branches, to 75 cm tall.
Axis:Present.
Branches:Terminal side branchlets (pinnules) 5-8 cm long, 2.5 mm in diameter, cylindrical, arising from all sides of main branches.
Apertures:Crowded, <1 mm across, sometimes with small lower lip; on all sides of branches and pinnules.
Mucus:None.
Color:Purple, purplish-pink, dull brown or buff white; dried colonies olive yellow, grayish yellow, reddish-brown, purple. Colony color depends on proportion of yellow and purple spindles in surface layer.
Sclerites:Outer layer: stout spindles with spines on one side, ~0.3 mm long, and asymmetrical clubs 0.20-0.25 mm long. Axial layer: slender, purple, acute spindles to 0.3 mm long.