Research Article |
Corresponding author: Leen P. van Ofwegen ( ofwegen@naturalis.nnm.nl ) Academic editor: Bert W. Hoeksema
© 2016 Leen P. van Ofwegen, Catherine S. McFadden, Yehuda Benayahu.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
van Ofwegen LP, McFadden CS, Benayahu Y (2016) Sinularia polydactyla (Ehrenberg, 1834) (Cnidaria, Octocorallia) re-examined, with the description of a new species. ZooKeys 581: 71-126. https://doi.org/10.3897/zookeys.581.7455
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Sinularia polydactyla (Ehrenberg, 1834) is re-described and a lectotype assigned. This led to examination of related material from various Indo-Pacific regions. Consequently, Sinularia levi sp. n. is described from Eilat, Israel (Gulf of Aqaba, northern Red Sea) and S. compressa Tixier-Durivault, 1945 and S. candidula Verseveldt and Benayahu, 1983 are synonymized with S. polydactyla. Additional specimens identified in the literature as S. polydactyla are provisionally reassigned to other taxa.
Alcyonacea , re-description, new species, Indo-Pacific, Red Sea, taxonomy, phylogeny, coral reefs, COI, mtMutS
The Indo-Pacific genus Sinularia, with an estimated number of ~190 nominal species, is the most speciose of the zooxanthellate, reef-dwelling octocoral genera (
During his revision of the soft coral genus Sinularia,
We also managed to find the material used by
While examining the syntypes of S. polydactyla, it became obvious that S. compressa Tixier-Durivault, 1945 and S. candidula Verseveldt & Benayahu, 1983 are very similar to S. polydactyla. As S. compressa was also included in the molecular study and also occurred in two different parts of the phylogenetic tree (
In order to identify the material, sclerites from different parts of each specimen were obtained by dissolving tissue in 10% sodium hypochlorite, followed by rinsing in fresh water. When appropriate, they were prepared for scanning electron microscopy as follows: the sclerites were carefully rinsed with double-distilled water, dried at room temperature, coated with gold and examined with a Jeol 6480LV electron microscope, operated at 10 kV.
Material studied is deposited in the
Published methods (
Phylogenetic analyses of mtMutS included sequences for 76 specimens identified as 44 morphospecies belonging to Sinularia Clade 4 (
Maximum likelihood tree of Sinularia Clade 4 (
Mean genetic distances (Kimura 2-parameter, ± s.d.) among mtMutS sequences within and between the clades of Sinularia highlighted in Fig.
S. levi sp. n. | S. polydactyla | W. Pacific clade | Guam clade | |
---|---|---|---|---|
S. levi sp. n. | 0.000 ± 0.0000 | |||
S. polydactyla | 0.030 ± 0.0006 | 0.001 ± 0.0007 | ||
W. Pacific clade | 0.038 ± 0.0026 | 0.011 ± 0.0023 | 0.005 ± 0.0031 | |
Guam clade | 0.035 ± 0.0007 | 0.009 ± 0.0021 | 0.013 ± 0.0028 | 0.005 ± 0.0040 |
ZMTAU 34181 | 0.031 ± 0.0000 | 0.007 ± 0.0007 | 0.013 ± 0.0023 | 0.011 ± 0.0024 |
COI sequences were available for only 42 of the 76 Clade 4 specimens, representing 24 morphospecies and 15 of 20 individuals of S. polydactyla and S. compressa. Results of the combined analysis of mtMutS and COI for this more limited dataset were congruent with and provided stronger ML bootstrap support for the same clades of S. polydactyla / S. compressa identified in the mtMutS tree (Suppl. material
Genetic distances among specimens in each of the two Red Sea clades ranged from 0–0.1%, suggesting that each of those clades represents a single species (Table
Lobularia polydactyla Ehrenberg, 1834: 58 (Red Sea).
? Sinularia polydactyla; Benayahu and Schleyer 1996: 6 (Mozambique); Benayahu et al. 2003: 56 (Mozambique);
Sinularia polydactyla (partly); Benayahu et al. 2002: 278 (Red Sea).
Sinularia compressa Tixier-Durivault, 1945: 150 (Red Sea);
Sinularia compressa (partly);
Sinularia candidula Verseveldt & Benayahu, 1983: 11 (Red Sea).
NOT Sinularia polydactyla; Verseveldt 1971: 4 (Madagascar); Tixier-Durivault 1972: 677 (Reunion; = S. shlagmani Benayahu & Ofwegen, 2012); Verseveldt 1972: 457 (Eniwetok Atoll, Marshall Islands); 1974: 96 (New Caledonia): 1977: 3 (Fiji, Guam, Samoa); 1978: 50 (Guam, Palau); 1980: 108 (older literature); Ofwegen and Benayahu 1992: 140 (Tanzania);
NOT Sinularia compressa; Benayahu 1997: 215 (Guam); 2002: 18 (Japan); Benayahu et al. 2004: 551 (Taiwan); Manuputty and Ofwegen 2007: 191 (Ambon); Benayahu and Chou 2010: 4 (Singapore).
The lectotype is 14.5 cm high and 9 cm wide (Figure
Sclerites. Polyps without sclerites. The surface layer of the lobules has clubs with a distinct central wart, the smallest are 0.07 mm long, most are around 0.10 mm, but some reach even a length of 0.15 mm (Figure
Colour. The alcohol-preserved specimen is light brown.
The two paralectotypes
Notably the Red Sea S. polydactyla colonies can be much larger than the lectotypes and have longer lobules (Figure
Sinularia compressa Tixier-Durivault, 1945 exhibits close similarity to S. polydactyla. It differs in having clubs in the surface layer of the lobes with more slender handle and spinier head. S. compressa specimens ZMTAU 34140, 34142, and 34150, all from the Red Sea (Figure
Finally, we re-examined the type of S. candidula Verseveldt & Benayahu, 1983,
Sinularia polydactyla (partly); Verseveldt 1971: 4 (Madagascar).
Sinularia polydactyla;
holotype: ZMTAU Co 34106, Eilat Nature Reserve, Gulf of Aqaba, northern Red Sea (Israel), 29°30.6'N, 34°55.35'E, depth 2.4-5.5 m, coll. Y. Benayahu, 24 July 2007; paratype: ZMTAU Co 34138, same data as holotype.
The holotype is 5.5 cm high and 3 cm wide (Figure
Sclerites. Polyps without collaret, but with points featuring poorly developed clubs, up to 0.15 mm long (Figure
Colour. The alcohol-preserved specimen is brown.
Named after the late Prof. Lev Fishelson, Tel Aviv University, pioneering and outstanding marine biologist, who investigated Red Sea coral reefs.
The paratype ZMTAU Co 34138 (Figure
Preserved specimens have a brown colony colour. In the
Material used by
Both molecular and morphological evidence suggest that other specimens identified in the recent literature as S. polydactyla or S. compressa belong to neither of the two species described here, but instead represent either misidentifications or as yet undescribed species. ZMTAU Co 34181 (Israel, Gulf of Aqaba, Eilat, south Oil Jetty, 29°31.05'N, 34°55.86'E, 1.5 m, coll. Y. Benayahu, 25 July 2007), previously identified as S. polydactyla, has a colony shape that differs from all other specimens examined, as it is not stalked but cup-shaped (Figure
Three of the nine specimens from the western Pacific that belonged to a well-supported clade within Clade 4D were not re-examined in the current study:
Material used by
Sinularia polydactyla, “PBH-C10”. A clubs of surface layer top of colony B spindles of the interior of the top of the colony C tuberculation of one of the spindles of the interior of the top of the colony D tuberculation of one of the spindles of the interior of the base of the colony E-F spindles of the interior of the base of the colony.
For this research (Application DE-TAF-662) Y.B. received support from the SYNTHESYS Project http://www.synthesys.info/, which is financed by European Community Research Infrastructure Action under the FP7 “Capacities” Program. The study also was in part supported by The Israel Cohen Chair in Environmental Zoology to Y.B. We would like to thank Dr. Carsten Lüter, Museum für Naturkunde der Humboldt Universität, Berlin, Germany, for entrusting us with the syntypes of S. polydactyla. We wish to thank Alex Shlagman for curatorial skills, Michal Weis and Asaul Gonzalez for technical assistance, Erez Shoham for underwater photographs, and the Interuniversity Institute for Marine Sciences in Eilat (IUI) for facilities.
Maximum likelihood phylogeny
Data type: Figure
Explanation note: Maximum likelihood phylogeny of Sinularia clade 4 based on a combined, partitioned analysis of mtMutS (735 bp) and COI + igr1 (815 bp). Numbers above branches are ML bootstrap percentages; numbers below branches are posterior probabilities from Bayesian Inference. Red: specimens identified in previous work as S. polydactyla; blue: specimens identified in previous work as S. compressa.
GenBank accession numbers
Data type: occurence
Explanation note: Specimens of Sinularia included in molecular phylogenetic analysis.