Astrogorgia fruticosa, Namin, Samimi & Ofwegen, Van, 2009

Namin, Samimi & Ofwegen, Van, 2009, Some shallow water octocorals (Coelenterata: Anthozoa) of the Persian Gulf, Zootaxa 2058, pp. 1-52 : 12

Astrogorgia fruticosa n. sp.

( Figs. 7a , 8 )

Material: Holotype, RMNH Coel. 38768, N of Hengam Island, washed ashore, coll. M. Hosein Pour Khalajani, 2006.

Description. The holotype is a colony fragment with part of the holdfast still present. It has a bushy colony shape and anastomoses, the latter mostly situated in the lower part of the colony. The colony is 22 cm high and about 12 cm wide, the main stem is 0.5 cm wide and branching starts at 0.5 cm above the holdfast ( Fig. 7a ). Polyps are situated all around the branches; calyces are about 1 mm high.

Polyps are retracted; the collaret has 6–7 rows of spindles and the points have many sclerites. These sclerites do not differ much from those of the calyx, and are up to 0.25 mm long, with simple tubercles or spines ( Fig. 8 a). Tentacle sclerites are similar to those of the points but slightly shorter, more flattened and less tuberculate ( Fig. 8 b).

The surface layer of the coenenchyme has spindles up to 0.60 mm long; with simple or complex tubercles ( Fig. 8 c–d). The interior of the coenenchyme has capstans and rods, up to 0.10 mm long, with simple tubercles ( Fig. 8 e).

Colour. Colony red, tentacle sclerites yellow, point sclerites partly yellow partly reddish; all other sclerites are reddish.

Etymology. The Latin “ fruticosa ”, bushy or full of bushes, refers to the colony form.

Remarks. Only three other species of Astrogorgia have been reported having a bushy colony form, A. arborea (Thompson & Simpson, 1909) from India, A. mengalia Grasshoff, 1999 from New Caledonia and A. balinensis Hermanlimianto & Ofwegen, 2006 from Bali. A. arborea has spindles up to 3.5 mm long and in A. mengalia they are up to 1.3 mm long; both much longer than the 0.60 mm of the present species. On the other hand A. balinensis has much shorter spindles, up to 0.25 mm long. Moreover, A. fruticosa has anastomoses, the other three bushy species do not.

Figures

FIGURE 8. Astrogorgia fruticosa n. sp., holotype RMNH Coel. 38768: a, polyp spindles; b, tentacular rods; c-d, coenenchymal spindles; e, capstans and rods of the subsurface layer. Scale at d only applies to d.

FIGURE 7. a, RMNH Coel. 38768, holotype of Astrogorgia fruticosa n. sp.; b, RMNH Coel. 38769, Echinogorgia sp. a; c, RMNH Coel. 38770, Echinogorgia sp. b; d, RMNH Coel. 38771, Echinogorgia sp. b. Scales 1 cm.