Alcyonium grandis Casas et al. 1997

Alcyonium grandis Casas et al ., 1997 (Figs. 1 b–c, 5, 11) Alcyonium grandis Casas et al ., 1997: 304, figs. 5–7. Material : RMNH Coel. 34936, fragment of colony, Chile, Islas Diego Ramírez/Drake Passage (approx. 56°30' S; 68°45' W), depth 1800 m, coll. Claudio Vera, 2001; ZSM 20061187, fr...

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Bibliographic Details
Main Author: Ofwegen, Van
Format: Other/Unknown Material
Language:unknown
Published: Zenodo 2007
Subjects:
Online Access:https://doi.org/10.5281/zenodo.6237495
http://treatment.plazi.org/id/7974B36EFFAC0948B1FAB663C623E948
Description
Summary:Alcyonium grandis Casas et al ., 1997 (Figs. 1 b–c, 5, 11) Alcyonium grandis Casas et al ., 1997: 304, figs. 5–7. Material : RMNH Coel. 34936, fragment of colony, Chile, Islas Diego Ramírez/Drake Passage (approx. 56°30' S; 68°45' W), depth 1800 m, coll. Claudio Vera, 2001; ZSM 20061187, fragment of colony, South Georgia, depth 1200 m, coll. Eugenio Olivares, September 2003. Description of RMNH Coel. 34936. The colony is membranous, about 1.5 cm long and 1cm wide (Fig. 1 c). Polyps are evenly distributed over the colony. Calyces are dome shaped and all polyps are partly retracted with tentacles withdrawn. Anthocodiae have a collaret of a few irregularly arranged rows of spindles; the points have many spindles. In order to preserve as much as possible of the fragment no microscope slides were made for drawing the anthocodial sclerite arrangement. The collaret spindles are up to 0.55 mm long, with spines and prominent simple tubercles (Fig. 5 a–b). Points have spindles similar to those of the collaret, with clubs present distally, up to 0.30 mm long (Fig. 5 c). The tentacles are without sclerites. The surface layer of calyces and membrane has exclusively capstans, 0.10–0.15 mm long (Fig. 5 d, h). The interior has tuberculated spindles (Fig. 5 f–g, i), the longest present in the calyces, up to 0.40 mm long. Some of these spindles are club-like (Fig. 5 e), but real clubs were not observed. Colour . The preserved colony is white, and all sclerites are colourless. Habitat, distribution and abundance. The species occurs in South Georgia, and was collected only once in Chile, at 1800 m depth. Remarks. ZSM 20061187 is also only a fragment, but a large part of that colony has been photographed, showing more of its colony shape (Fig. 1 b). The species was originally described from off Shag Rocks and South Georgia, at 152–335 m depth (Casas et al ., 1997: 308). All six colonies of the type series showed colonies with numerous lobes, the largest colony, the holotype, even reaching 16.5 cm in height. It is remarkable that the ...