A revision of the genus Eugorgia Verrill, 1868 (Coelenterata: Octocorallia: Gorgoniidae)
Author
Breedy, Odalisca
Author
Guzman, Hector M.
Author
Vargas, Sergio
text
Zootaxa
2009
2151
1
46
journal article
10.5281/zenodo.188707
bf88cf54-38da-4ec6-a560-6c1ea86bf792
1175-5326
188707
Eugorgia alba
Bielschowsky, 1929
comb. nov.
Figures 3
A–C, 4
Eugorgia bradleyi
var.
alba
Bielschowsky, 1929
: 177
–178;
Kükenthal 1924
: 345
.
Material examined
.
Holotype
:
ZMHC
2243, ethanol preserved, Acajutla,
El Salvador
, no further data.
Description.
The
holotype
is a small colony,
5 cm
in height and
3 cm
in width. Branching is irregularly dichotomous (
Fig. 3
A). Two main branches arise from a short stem,
1.2 cm
long, and subdivide up to three times. The holdfast is missing from the
holotype
, but from Bielschowsky’s illustration (1929: plate 3, fig.15) it seems incrusting. Branches are slightly compressed in cross section,
3 mm
in diameter at the base and tapered, more rounded at the branchlets. Branchlets are up to
2 mm
in diameter. Unbranched final twigs reach up to
3 cm
with pointed tips, about
1 mm
in diameter. Polyps retract within slightly raised polyp-mounds with oval apertures (
Fig. 3
B). Polyp-mounds are distributed in 2–4 longitudinal rows on the branches, and sparsely placed. Colour of the colony is white. Sclerites of the coenenchyme are mostly colourless, some with a pale pink hue. They are mostly double discs reaching up to
0.075 mm
in length, and
0.06 mm
in width (
Fig. 3
C, 4). Spindles reach up to
0.13 mm
in length, and
0.05 mm
in width, with 4–6 whorls of tubercles, with ends mostly acute. No anthocodial rods were found in the samples.
Distribution.
Known only from the
type
locality (
Table 4
).
FIGURE 3
.
Eugorgia alba
, holotype: A, colony; B, detail of branches; C, coenenchymal sclerites.
FIGURE 4.
Eugorgia alba
holotype, coenenchymal sclerites.
Remarks.
Bielschowsky (1929)
described this species with a specimen from the coast of
El Salvador
and assumed it to be a variety of
E. bradleyi
. Although the
holotype
is the sole specimen of this species and thus we cannot consider intera-specific variability; we consider that the differences between
E. bradleyi
and
E. bradleyi
var.
alba
are sufficient to regard them as different species. Moreover, there are no records of
E. bradleyi
from the coast of
El Salvador
at present, but exploration there has been minimal. External morphology and colour of
E. alba
are very consistent with
Leptogorgia alba
Duchassaing & Michelotti, 1864
; however, the sclerites, and especially the presence of double discs in of the former, places it in this different genus.