Nanalcyon, Ima, 2013

Ima, Yukimitsu, 2013, Two new paralcyoniid octocorals from Japan (Anthozoa: Alcyonacea), Zootaxa 3652 (4), pp. 424-436 : 430

Genus Nanalcyon n. gen.

Monomorphic Paralcyoniidae with polyparium dome-shaped in expanded condition. Colonies usually independent and not connected to each other by stolons. Several widely spaced primary polyps distributed over whole surface of polyparium, and single secondary polyps arising near proximal part of anthostele of several primary polyps. Tentacles devoid of sclerites except for a few elongated platelets gathered proximally. Polyps with many elongated rods arranged in chevrons in the point, and additionally several rods of same kind arranged transversely below the point. Trunk with a few short rods in cortex of circumference of only some polyps. Cortex of pedicel with many almost longitudinally arranged long spindles with small, complex warts, spindles in upper part sometimes tending to be arranged longitudinally in eight chevrons. Inner layer of trunk and pedicel entirely devoid of sclerites. No zooxanthellae in tissue.

Differentiation. This genus closely resembles the Mediterranean and Atlantic genus Maasella in colony appearance. It obviously differs, however, in producing secondary polyps from the primary polyps and in the independent existence of the colonies. The new genus also closely resembles the Mediterranean genus Paralcyonium in having secondary polyps that arise from the anthosteles of the primary polyps, and in being devoid of sclerites in the tentacles. It differs in that the primary polyps are not developed into branches. Although the present colonies are extremely small, they are mature, with many gonads in their gastric cavities.

Etymology: From the Latin "nanus", a dwarf, in reference to the small size of colony.