A revision of the octocoral genus Ovabunda Alderslade, 2001 (Anthozoa, Octocorallia, Xeniidae)
Author
Halasz, Anna
Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
Author
McFadden, Catherine S.
Department of Biology, Harvey Mudd College, 1250 N. Dartmouth Ave., Claremont, CA 91711, USA
Author
Aharonovich, Dafna
Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
Author
Toonen, Robert
Hawai'i Institute of Marine Biology, University of Hawaii at Manoa, 46 - 007 Lilipuna Road, Kane'ohe, HI 96744, USA
Author
Benayahu, Yehuda
Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
text
ZooKeys
2014
2014-01-23
373
1
41
http://dx.doi.org/10.3897/zookeys.373.6511
journal article
http://dx.doi.org/10.3897/zookeys.373.6511
1313-2970-373-1
A246FFD7FFADFF9EFFAAAF06FFDCCB03
577685
Ovabunda crenata (Reinicke, 1997)
comb. n.
Fig. 10
Xenia crenata
Reinicke, 1997: 41-42, figs 3c, 15; plates 5, 25.
Material.
Holotype:
RMNH Coel. 23538, Sudanese Red Sea, Sanganeb Atoll, 20 km off Port Sudan, S-slope near jetty (
19°21'33.81"N
,
37°19'37.66"E
), 10 m, April 1991, coll. G.B. Reinicke;
additional material:
RMNH Coel. 23517, Sudanese Red Sea, Sanganeb Atoll, lagoon slope, TQ II station, 8 m, March 1991, coll. G.B. Reinicke;
type of
Xenia viridis
SMF 42, Indonesia, Ternate island, 1894, coll.
Kuekenthal
;
type of
Xenia blumi
SMF 44, Indonesia, Ternate island, 1894, coll.
Kuekenthal
.
Description.
The holotype is 30 mm high and 10 mm wide at its base. The stalk splits into two branches. The first is 15 mm long, 6 mm wide at its base and 10 mm wide at its uppermost part; the second splits further into two branches, 15 and 7 mm long, each 5 mm wide at the base, and 10 and 7 mm wide at the upper part, respectively.
Polyp's
body is up to 5 mm long and the tentacles up to 5 mm long. The pinnules are mostly arranged in two rows, with an occasional third row. There are 12-16 pinnules in the outermost row, 1 mm long and 0.14 mm wide, with a 0.2 mm space between adjacent pinnules. Sclerites are very scarce in all parts of the holotype; they are
Ovabunda
-type spheroids, measuring 0.012-0.028
x
0.018-0.036 mm in diameter (n = 35 sclerites). Occasionally, two sclerites are fused, reaching 0.050 mm in maximal diameter. SEM micrographs of sclerites were obtained only from the additional material due to low density of sclerites in the holotype.
Reinicke (1997)
recorded non-pulsating polyps for the species. The ethanol preserved holotype is light beige.
Remarks.
RMNH Coel. 23517 is similar in size to the holotype.
Polyp's
body is up to 2 mm long, with 2 mm long tentacles, mostly bearing two rows of 1 mm long
and
0.1 mm wide slender pinnules on each of the tentacle sides, and, rarely, a third row. The outermost row features 12-15 pinnules, up to one pinnule-width apart. Sclerites are of the
Ovabunda
-type, varying in shape from regular (
Fig. 10a
), egg-shaped (
Fig. 10c
) and more rectangular (
Fig. 10d
), ranging 0.016-0.026
x
0.028-0.040 mm (n = 25 sclerites) in diameter. Occasionally, two sclerites are fused, reaching 0.047 mm in maximal diameter (
Fig. 10b
).
Figure 10.
Scanning electron micrographs of polyp sclerites of
Ovabunda crenata
(Reinicke, 1997) (RMNH Coel. 23517).
a
Regular sclerites
b
Fused sclerites
c
Egg-shaped sclerites
d
Rectangular sclerite. Arrows indicate surface dents. Scale bar 10
µm
.
Reinicke (1997)
noted under the description of
Xenia crenata
sp. n. (p. 41): "?
Xenia blumi
Schenk 1896
;
Gohar 1940
: 98,
Plate 5
" and "
Xenia blumi
Schenk 1896
sensu Gohar -
Reinicke 1995
: 42, Fig. 31".
Reinicke (1997)
also noted: "?
Xenia viridis
Schenk 1896
;
Benayahu 1990
: 115 (listed)". The description of
Xenia blumi
according to
Gohar (1940)
does not match
Ovabunda crenata
features. Examination of the types of
Xenia blumi
and
Xenia viridis
during the current study (see
Table 1
) revealed them to have platelet-shaped sclerites composed of dendritic rods, and to differ from
Ovabunda crenata
.
Conclusions
.
The original description of the holotype indicated three rows of pinnules, whereas the present examination revealed mostly two rows, with an indication of a third one. There is agreement between our findings and the original description regarding the number of pinnules in the outermost row of the tentacles (12-16
vs.
12-15, respectively). Sclerites correspond to the original description in size but are
Ovabunda
-type spheroids; therefore, it is concluded that the species should be assigned to
Ovabunda
.
Similar species.
Ovabunda crenata
is most similar to
Ovabunda biseriata
. Although they both have overlapping number of pinnules in the outermost row, 12-16 and 13-16, respectively,
Ovabunda biseriata
has two rows of pinnules and
Ovabunda crenata
occasionally presents a third row. They both have non-pulsating polyps in live colonies.
Distribution.
Red Sea: Gulf of Aqaba, Sudan.