Search Results (6)

The rapid reduction in coral reefs worldwide has led to increasing attention toward protecting and restoring coral reef ecosystems. Coral reefs not only have a rich diversity of coral species, but they can also provide important products and services for human beings. One type of coral, Echinogorgia, has important scientific research value and application prospects. To understand the diversity of coral species, diving surveys were conducted in Xiamen Bay in 2017 and 2021, and a total of 928 samples were collected. Taxonomic research was conducted using methods such as morphological identification through electron microscopy. Specific phylogenetic trees of the COI gene, mtMuts gene, and ITS1 gene were analyzed. There were 47 specimens of Echinogorgia coral included among 928 samples. Fifteen species of Echinogorgia were identified, including Echinogorgia ramosa, Echinogorgia flexilis, Echinogorgia russelli, Echinogorgia ramulosa, and Echinogorgia gracilima (which represent the newly recorded species in the waters of China). This study increases the species diversity records in China and contributes to new geographical distribution information of Echinogorgia worldwide. The primary data also serve as the baseline data for long-term biomonitoring programs to estimate the status of octocorals in Xiamen Bay. Full article

The monotypic soft coral genus Stragulum van Ofwegen and Haddad, 2011 (Octocorallia: Malacalcyonacea: Tubiporidae) was originally described from Brazil, southwest Atlantic Ocean. Here, we report the first records of the genus from the eastern Caribbean and the Persian Gulf in the northwest Indian Ocean. We compare the morphological features of specimens, together with molecular data from three commonly used barcoding markers (COI, mtMutS, 28S rDNA) and 308 ultraconserved elements (UCE) and exon loci sequenced using a target-enrichment approach. The molecular and morphological data together suggest that specimens from all three localities are the same species, i.e., Stragulum bicolor van Ofwegen and Haddad, 2011. It is still not possible to establish the native range of the species or determine whether it may be an introduced species due to the limited number of specimens included in this study. However, the lack of historical records, its fouling abilities on artificial substrates, and a growing number of observations support the invasive nature of the species in Brazilian and Caribbean waters and therefore suggest that it may have been introduced into the Atlantic from elsewhere. Interestingly, the species has not shown any invasive behaviour in the Persian Gulf, where it has been found only on natural, rocky substrates. The aim of the present report is to create awareness of this taxon with the hope that this will lead to new records from other localities and help to establish its native range. Full article

Deep-sea corals are important benthic inhabitants that support the biodiversity and function of the wider faunal community; however, their taxonomy is underdeveloped and their accurate identification is often difficult. In our study, we investigated the utility of a superextended (>3000 bp) barcode and explored the effectiveness of various molecular species delimitation techniques with an aim to put upper and lower bounds on the estimated number of calcaxonian species in Irish waters. We collected 112 calcaxonians (70 Keratoisididae, 22 Primnoidae, 20 Chrysogorgiidae) and one chelidonisid from the Irish continental slope and sequenced a 3390 bp DNA barcode comprising four mitochondrial regions (mtMutS, COI + igr1, 16S rRNA-ND2, and igr4), recovering 38 haplotypes. Individuals that shared a haplotype were often morphologically distinct, and we thus undertook detailed morphological work, including SEM of sclerites, on one representative of each morphotype within each haplotype. GMYC, bGMYC, and mPTP returned incongruent estimates of species numbers. In total, there are between 25 and 40 species, although no definitive number could be assigned, primarily due to poorly defined keratoisidid species boundaries. As expected, the superextended barcode provided greater discrimination power than single markers; bGMYC appeared to be the most effective delimiter. Among the identified species were Chelidonisis aurantiaca, collected deeper than previously known at 1507 m, and Calyptrophora clinata, recorded for the second time from the Northeast Atlantic. A full understanding of the diversity and distribution of calcaxonians requires substantial taxonomic work, but we highlight the Irish continental slope as harbouring significant diversity. Full article

Mesophotic Coral Ecosystems (MCEs) develop on a unique environment, where abrupt environmental changes take place. Using a time-calibrated molecular phylogeny (mtDNA: mtMutS), we examined the lineage membership of mesophotic gorgonian corals (Octocorallia: Cnidaria) in comparison to shallow and deep-sea lineages of the wider Caribbean-Gulf of Mexico and the Tropical Eastern Pacific. Our results show mesophotic gorgonians originating multiple times from old deep-sea octocoral lineages, whereas shallow-water species comprise younger lineages. The mesophotic gorgonian fauna in the studied areas is related to their zooxanthellate shallow-water counterparts in only two clades (Gorgoniidae and Plexauridae), where the bathymetrical gradient could serve as a driver of diversification. Interestingly, mesophotic clades have diversified faster than either shallow or deep clades. One of this groups with fast diversification is the family Ellisellidae, a major component of the mesophotic gorgonian coral assemblage worldwide. Full article

Members of genus Iridogorgia Verrill, 1883 are the typical deep-sea megabenthos with only seven species reported. Based on an integrated morphological-molecular approach, eight sampled specimens of Iridogorgia from seamounts in the tropical Western Pacific are identified as three new species, and two known species I. magnispiralis Watling, 2007 and I. densispicula Xu, Zhan, Li and Xu, 2020. Iridogorgia flexilis sp. nov. is unique in having a very broad polyp body base with stout and thick scales. Iridogorgia densispiralis sp. nov. can be distinguished by rods present in both polyps and coenenchyme, and I. verrucosa sp. nov. is characterized by having numerous verrucae in coenenchyme and irregular spindles and scales in the polyp body wall. Phylogenetic analysis based on the nuclear 28S rDNA indicated that I. densispiralis sp. nov. showed close relationships with I. splendens Watling, 2007 and I. verrucosa sp. nov., and I. flexilis sp. nov. formed a sister clade with I. magnispiralis. In addition, due to Rhodaniridogorgia fragilis Watling, 2007 nested into the Iridogorgia clade in mtMutS-COI trees and shared highly similar morphology to the latter, we propose to eliminate the genus Rhodaniridogorgia by establishing a new combination Iridogorgia fragilis (Watling, 2007) comb. nov. and resurrecting I. superba Nutting, 1908. Full article

Mesophotic coral ecosystems (MCEs) are recognized around the world as diverse and ecologically important habitats. In the northern Gulf of Mexico (GoMx), MCEs are rocky reefs with abundant black corals and octocorals, including the species Swiftia exserta. Surveys following the Deepwater Horizon (DWH) oil spill in 2010 revealed significant injury to these and other species, the restoration of which requires an in-depth understanding of the biology, ecology, and genetic diversity of each species. To support a larger population connectivity study of impacted octocorals in the GoMx, this study combined sequences of mtMutS and nuclear 28S rDNA to confirm the identity of Swiftia sea fans in the GoMx, compare these markers for different polyp colors in the GoMx and Atlantic, and examine the phylogeny of the genus. Two mtMutS haplotypes were identified, one seemingly endemic to the northern GoMx. Compared to other North Atlantic Swiftia, S. exserta, the type of the genus was found to be extremely divergent and distinct from the two other Swiftia at both loci, with strong evidence of polyphyly in the genus. This information refines our understanding of the geographical distribution of injured coral and highlights how little is known about MCEs. Substantial taxonomic revisions may be needed for several taxa injured by the DWH oil spill. Full article