Family Ellisellidae
Viminella
barbadensis (Duchassaing
& Michelotti, 1864)
Juncella barbadensis Verrill, 1864:22. pl.
5 figs. 5-6.
Remarks. Viminella barbadensis is one of several ellisellid species that have been the subject of reclassification in the last two decades. Bayer and Grasshoff (1994) suggested that unbranched species of Ellisella be placed into the genus Viminella based on Kukenthal’s (1924) classification,and that Viminella [Ellisella]is a subgenus of Ctenocella. Grasshoff (1999) removed the subgenus status and placed ellisellids with unbranched growth forms (“whips”) under the genus Viminella, establishing the basis for the new combination presented in this document.
The specimens examined for this work do not exhibit the large stem diameter and crowded polyps discussed by Bayer (1961), but variability of these characters has been noted (Deichmann, 1936). The SERTC and USNM colonies are all unbranched, slender colonies (1–2 mm in diameter exclusive of polyps) with polyps arranged biserially in a row on each side in a somewhat alternating pattern. The polyps are very prominent and sometimes upturned, except in a few areas where the coenenchyme appears ‘inflated’ and the polyps are reduced. The color of the preserved colonies varies from pale to deep orange, with a very dense, white axis. As is diagnostic of the Ellisellidae, the axis does not have a hollow central core and is comprised of calcareous material that is accreted in a concentric manner in radial sectors. In some cases where the polyps are not as prominent, the slender colonies of V. barbadensis may resemble colonies of Leptogorgia euryale; microscopic examination of the axis characteristics and absence of colored spindles will readily distinguish V. barbadensis from members of the Gorgoniidae.
The sclerites examined from the tip of the USNM specimen are dominated by amber, tuberculated double heads, double cones and warty rods. Other specimens examined contain double heads that are more coarsely tuberculated, perhaps a function of the location of the subsample on the colony. Many of the double-headed sclerites have a notable degree of granulation on the tips of the tubercles. The largest double cones or spindles are no more than twice the length of the double heads.
This species can reach a very large size in some parts of the tropical Atlantic, reaching a few meters in length and almost a centimeter in diameter.
Note: A small ellisellid fragment was found among a lot of Leptogorgia specimens and was tentatively identified as Nicella cf. schmitti (Breedy, pers. comm.). The fragment is too small to reveal the characteristic branching of this species, thus precluding the addition of N. schmitti to this guide. Although there are no records of N. schmitti occurring north of Boca Raton, Florida (approximately 26°22’ N), the presence of N. schmitti in the shallow SAB is possible.
Atlantic distribution: South Carolina to Brazil, Gulf of Mexico, Caribbean, 12–453 m (Deichmann 1936; Bayer 1961; NMNH collections; SERTC collection).
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Figure 1. Viminella barbadensis, preserved
specimens (S2629), sections of colony stem (scale bars = 1 mm respectively)
Figure 2. Solid axis of Viminella
barbadensis (USNM 50395, scale bar = 0.5mm).
Figure 3. Sclerites of Viminella
barbadensis (USNM 50395); a-e)double heads from coenenchyme;
f) flattened double cone from calyx; g) small flattened rod from
polyp (scale bar = 20 µm).
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