Center Of Marine Biodiversity Research Articles

Tropical seamounts as stepping-stones for coral reef fishes: range extensions and new regional distributions from mesophotic ecosystems in the Coral Sea, Australia

Seamounts and remote oceanic islands serve as valuable natural laboratories in which to study patterns and processes in marine biodiversity. A central hypothesis arising from studies of these systems is the ecological function of seamounts as stepping-stones for dispersal and population connectivity. Evidence of this mechanism exists for a range of taxa, including coral reef fishes, but is still lacking from many tropical seamounts in remote regions. In this study, we used remotely operated vehicles and baited remote underwater video systems to survey fish and benthic communities between 1 and 100 m on seamounts in the Coral Sea Marine Park (CSMP), Australia. We found evidence to support the stepping-stone model of ecological connectivity from new observations of 16 coral reef fishes which have previously not been recorded by quantitative surveys in the region. The widespread distribution of many of these species throughout the full latitudinal extent of the CSMP suggests that there is greater connectivity between mesophotic habitats in the Coral Sea and surrounding biogeographic regions than previously known. We also found a wide variety of mesophotic habitats and recorded significant depth range extensions for 78 fishes in these habitats. This further highlights the potential role of increased habitat area and heterogeneity in a stepping-stone effect throughout the region. Four of the fish occurrence records represent significant range extensions into the Coral Sea from adjacent biogeographic regions, and 13 fishes recorded by this study in the CSMP are not known from the neighbouring Great Barrier Reef, despite its close proximity. Although the Coral Sea remains relatively understudied, these findings suggest that larger-scale models of marine biogeography are relevant to communities in the region, particularly at mesophotic depths. Given the extent and the spatial arrangement of seamounts in the Coral Sea, our findings emphasise that the region is an important link between the centre of marine biodiversity in the Coral Triangle and the Southwest Pacific. Greater mesophotic sampling effort and genetic studies are necessary to understand the nature of connectivity and to establish the role of regional seamount chains, like the Coral Sea reefs, in broader marine biogeographic processes.

Strong genetic structure and limited connectivity among populations of Clark’s Anemonefish (Amphiprion clarkii) in the centre of marine biodiversity

Populations of anemonefish species often show signs of local isolation due to limited dispersal potential and oceanographic conditions. Additionally, anthropogenic pressure, such as overharvesting and coral reef exploitation causes reduced population size, eventually leading to local extinction. The understanding of the genetic population structure, as well as the influence of both historical and current connectivity, is required to design effective marine protected area (MPA) networks. In this study, the genetic structure of Clark’s Anemonefish (Amphiprion clarkii) based on 209 individuals from 16 samples sites in the Indo-Malay Archipelago (IMA) is assessed through mitochondrial control region (mtCR) sequences and eight nuclear microsatellite loci. Results provided evidence of a significant genetic structure (mtCR: Φst = 0.42, Φct = 0.64; microsatellites: Fst = 0.01, Fct = 0.05). Genetic breaks were identified among Western (Padang Karimunjawa), Central (Sulawesi, Borneo, Bali, Komodo, Timor) and Eastern (Biak) IMA populations, with almost no gene flow. This matches with patterns obtained for congeneric and other coral reef taxa. Due to the restricted connectivity among these three regions, it is suggested to consider them as separate management areas in the design of MPA networks.

A Sustainable and Inclusive Blue Economy for the Philippine Archipelago

The Philippine Archipelago is surrounded by the West Pacific Ocean region on its eastern seaboard and the West Philippine Sea on the west. It is the apex of a coral-rich area known as the Coral Triangle, the center of marine biodiversity. The Filipino people have a long history of affinity to the sea that has been used as a source of food and means of transport and trade/business, yet the maritime potential of the country has not been fully utilized to propel its overall development using the blue economy platform. The status and potentials of the country in the fields of fisheries and aquaculture, marine biotechnology, ocean energy and transport, and manpower and infrastructure development for an integrated and future responsive development of a sustainable and inclusive blue economy are presented in this paper. The discussions encompass the twin goals of the blue economy, which are the inclusive growth of the people and protection of the marine resources.

Species check-list for Tintinnids of the Philippines Archipelago (Protozoa, Ciliophora)

Tintinnids are an essential link between nano- and macro- planktons in the food webs of the marine environment. It is also known that tintinnids are one of themajor components of marine planktonic ciliates and has a cosmopolitan character. In the Philippine archipelago, which is recognized as a center of marine biodiversity, tintinnids checklist has not been done or published. Therefore, a checklist is presented in this study based on a compilation of previous tintinnids studies conducted at the Philippines waters. As a result of the studies done since 1941 up to present, a total of 114 taxa belonging to 14 families and 37 genera were listed. The Philippines coastal waters record a total of 50 species while the open seas document 72 species to date.

An Overview of Marine Mammals in Eastern Indonesia 2016: Implications for Marine Mammals Research and Conservation

Eastern Indonesia is known as the center of marine biodiversity of the world as well as habitat and marine mammal migration path. Not all marine mammal events in eastern Indonesia are well documented. The purpose of this study was to determine the occurrence of marine mammals in eastern Indonesia in 2016. Data collection done through observation, indepth interview with the community and experts. The results of this study were 8 (eight) occurrences of marine mammals which were in Mollucas, North Mollucas and West Papua Provinces with the highest incidence in August. That marine mammals were Duyung (Dugong dugon), Sperm Whale(Physetermacrocephalus), Risso’s Dolphin(Grampus griseus), and 2 types of unidentified Whales. The marine mammals exist were deliberately netted by people, stranded, trapped in fishing nets or deliberately commercialized. This marine mammals stranded occurence indicate the requirement of strategies development for handling these protected marine ‘biota’ to store their population.

Comparative genetic population structure of three endangered giant clams (Cardiidae:Tridacnaspecies) throughout the Indo-West Pacific: implications for divergence, connectivity and conservation

Information on the genetic population structure of endangered giant clams is important for conservation programmes and the understanding of ecological and evolutionary processes. In this study, the genetic population structures of three codistributed and ecologically similar giant clam species (Tridacna crocea, T. maxima and T. squamosa) are compared. A fragment of the cytochrome c oxidase I gene was sequenced as a genetic marker in three giant clam species sampled throughout the Indo-West Pacific, from the Western Indian Ocean (WIO) and Red Sea (RS) to the Eastern Indian Ocean (EIO), across the centre of marine biodiversity in the Indo-Malay Archipelago (IMA) to the Western Pacific (WP) and the Society Islands in the Central Pacific (CP). All three species showed limited gene flow and a highly significant genetic population structure. The Phi(st)-values (P < 0.001) are 0.46, 0.81 and 0.68 for T. crocea, T. maxima and T. squamosa, respectively. Based on a hierarchical AMOVA they could be divided into three to six groups from West to East: (1) WIO (T. maxima and T. squamosa), (2) RS (T. maxima and T. squamosa), (3) EIO (including Java Sea in T. maxima), (4) central IMA, (5) WP and (6) CP (T. maxima). The distribution of the haplotype clades in the populations and the pairwise Fst-values between populations indicated a high level of gene flow in the central IMA for the three species. The concordant patterns suggest that geological history, sea-level changes during glacial periods of the Pliocene and Pleistocene, and oceanography are important factors shaping the genetic population structure of giant clams. The observed deep evolutionary lineages in the peripheral areas of the IMA might include cryptic species.

Delineating biophysical environments of the Sunda Banda Seascape, Indonesia.

The Sunda Banda Seascape (SBS), located in the center of the Coral Triangle, is a global center of marine biodiversity and a conservation priority. We proposed the first biophysical environmental delineation of the SBS using globally available satellite remote sensing and model-assimilated data to categorize this area into unique and meaningful biophysical classes. Specifically, the SBS was partitioned into eight biophysical classes characterized by similar sea surface temperature, chlorophyll a concentration, currents, and salinity patterns. Areas within each class were expected to have similar habitat types and ecosystem functions. Our work supplemented prevailing global marine management schemes by focusing in on a regional scale with finer spatial resolution. It also provided a baseline for academic research, ecological assessments and will facilitate marine spatial planning and conservation activities in the area. In addition, the framework and methods of delineating biophysical environments we presented can be expanded throughout the whole Coral Triangle to support research and conservation activities in this important region.

Exploring the role of Micronesian islands in the maintenance of coral genetic diversity in the Pacific Ocean.

Understanding how genetic diversity is maintained across patchy marine environments remains a fundamental problem in marine biology. The Coral Triangle, located in the Indo-West Pacific, is the centre of marine biodiversity and has been proposed as an important source of genetic diversity for remote Pacific reefs. Several studies highlight Micronesia, a scattering of hundreds of small islands situated within the North Equatorial Counter Current, as a potentially important migration corridor. To test this hypothesis, we characterized the population genetic structure of two ecologically important congeneric species of reef-building corals across greater Micronesia, from Palau to the Marshall Islands. Genetic divergences between islands followed an isolation-by-distance pattern, with Acropora hyacinthus exhibiting greater genetic divergences than A.digitifera, suggesting different migration capabilities or different effective population sizes for these closely related species. We inferred dispersal distance using a biophysical larval transport model, which explained an additional 15-21% of the observed genetic variation compared to between-island geographical distance alone. For both species, genetic divergence accumulates and genetic diversity diminishes with distance from the Coral Triangle, supporting the hypothesis that Micronesian islands act as important stepping stones connecting the central Pacific with the species-rich Coral Triangle. However, for A.hyacinthus, the species with lower genetic connectivity, immigration from the subequatorial Pacific begins to play a larger role in shaping diversity than input from the Coral Triangle. This work highlights the enormous dispersal potential of broadcast-spawning corals and identifies the biological and physical drivers that influence coral genetic diversity on a regional scale.

Pericelis cata Marcus and Marcus, 1968 (Platyhelminthes: Polycladida): first record from northeast of Brazil

The polyclad Pericelis cata has been reported in two distinct localities along the North Atlantic: Curaçao and the Caribbean coast of Colombia. Recently identified from the Southwestern Atlantic, the species was first described from the Cabo Frio region (23°S) (Rio de Janeiro State), a transitional zone between warm and cold water species located southeastern Brazil. The second location is in the northeastern coast in warm waters, in the entrance of the Todos-os-Santos Bay, a geographic area within the Brazilian Biotic Province, an important center of marine biodiversity of the Tropical Atlantic.

Strong genetic population structure in the boring giant clam, Tridacna crocea, across the Indo‐Malay Archipelago: implications related to evolutionary processes and connectivity

Even though the Indo-Malay Archipelago hosts the world's greatest diversity of marine species, studies on the genetic population structure and gene flow of marine organisms within this area are rather rare. Consequently, not much is known about connectivity of marine populations in the Indo-Malay Archipelago, despite the fact that such information is important to understand evolutionary and ecological processes in the centre of marine biodiversity. This study aims to investigate the genetic population structure of the boring giant clam, Tridacna crocea. The analysis is based on a 456-bp fragment of the cytochrome oxidase I gene from 300 individuals collected from 15 localities across the Indo-Malay Archipelago. Tridacna crocea shows a very strong genetic population structure and isolation by distance, indicating restricted gene flow between almost all sample sites. The observed Phi(ST)-value of 0.28 is very high compared to other studies on giant clams. According to the pronounced genetic differences, the sample sites can be divided into four groups from West to East: (i) Eastern Indian Ocean, (ii) Java Sea, (iii) South China Sea, Indonesian throughflow, as well as seas in the East of Sulawesi, and (iv) Western Pacific. This complex genetic population structure and pattern of connectivity, characterised by restricted gene flow between some sites and panmixing between others can be attributed to the geological history and prevailing current regimes in the Indo-Malay Archipelago.

Contrasting patterns in species boundaries and evolution of anemonefishes (Amphiprioninae, Pomacentridae) in the centre of marine biodiversity

Many species of coral reef fishes are distinguished by their colour patterns, but genetic studies have shown these are not always good predictors of genetic isolation and species boundaries. The genus Amphiprion comprises several species that have very similar colouration. Additionally, morphological characters are so variable, that sibling species can show a considerable overlap, making it difficult to differentiate them. In this study, we investigated the species boundaries between the sibling species pair A. ocellaris and A. percula (Subgenus Actinicola) and three closely related species of the subgenus Phalerebus ( A. akallopisos, A. perideraion, A. sandaracinos) by phylogenetic analysis of mitochondrial cytochrome b and control region sequences. These two subgenera show strong differences in their patterns of species boundaries. Within the A. ocellaris/ A. percula complex, five clades were found representing different geographic regions. Two major divergences both with genetic distances of 4–7% in cty b and 17–19% in the d-loop region indicate the presence of three instead of two deep evolutionary lineages. The species of the subgenus Phalerebus show three monophyletic clades, independent of the geographical location of origin, but concordant to the morphological species classification. The genetic distances between the Phalerebus species were 2–5% in cty b and 10–12% in the control region.

On estimating diversity in species‐rich fish assemblages: an example with coral‐reef fishes of eastern Indonesia

A new procedure for estimating fish species richness in open or semi‐open habitats is presented with unpublished data on the coral‐reef fish assemblages of Raja Ampat, eastern Indonesia, known as the centre of marine biodiversity in the western Pacific.

Evolutionary and biogeographical patterns within the smelt genusHypomesusin the North Pacific Ocean

AbstractAim We address questions about trans‐Pacific distributions of marine organisms and the North Pacific Ocean as a centre of marine biodiversity through a phylogenetic and biogeographical study of a pan‐Pacific genus of Northern Hemisphere smelts (Hypomesus, Pisces: Osmeridae).Location North Pacific Ocean.Methods Relationships of the five species ofHypomesusfrom throughout the North Pacific were reconstructed through maximum likelihood and Bayesian phylogenetic analyses of sequence data from two mitochondrial (cytb, 16S) and three nuclear (ITS2, S71, RAG1) gene regions of five to 25 individuals per species, totalling 3588 characters. The resulting phylogenies were used to test hypotheses of species relationships and geographical origins using both dispersal‐based and maximum likelihood methods for inferring ancestral areas (lagrange). Cytbsequence divergence and a Bayesian approach (beast) were used to estimate the timeframe ofHypomesusevolution, which was compared with work on similarly distributed taxa.Results Hypothesized trans‐Pacific Ocean relationships based on lateral line scale counts were not supported by the phylogeny, suggesting parallel evolution of this phenotype, although we found one such relationship between the westernH. japonicusand the two eastern Pacific species (H. pretiosusandH. transpacificus). Dispersalist approaches rejected an early proposal of a double‐compression vicariant mechanism as well as an eastern Pacific origin. Results from thelagrangeanalysis suggested a more widespread ancestor, although also supporting a role for the western Pacific. Divergence estimates suggested that most splits between species occurred in the mid‐Miocene, and the most recent speciation event, between the eastern Pacific species, occurred in the Pliocene to early Pleistocene.Main conclusions Our molecular data indicate that the character historically used to define relationships withinHypomesus, lateral line scale count, does not reflect ancestry within the genus. Biogeographical reconstructions suggest an important role for the western North Pacific in the diversification ofHypomesus. While uncertainty remains over the date of origin for this genus, estimates place the divergences during periods of climatic cooling that have been important in generating diversity in a number of similarly distributed organisms. Additional comparative data will provide further insight into the relative importance of the western region in generating diversity in the North Pacific Ocean.

The center of the center of marine shore fish biodiversity: the Philippine Islands

Multiple datasets show global maxima of marine biodiversity in the Indo–Malay–Philippines archipelago (IMPA). Analysis of distribution data for 2983 species reveals a pattern of richness on a finer scale and identifies a peak of marine biodiversity in the central Philippine Islands and a secondary peak between peninsular Malaysia and Sumatra. This pattern is repeated in diverse habitat and higher taxa classes, most rigorously for marine shore fishes, supporting geohistorical hypotheses as the most general unifying explanations. Specific predictions based on area of overlap, area of accumulation, and area of refuge hypotheses suggest that present day eastern Indonesia, or Wallacea, should be the center of marine biodiversity. Processes suggested by these three hypotheses contribute to the diversity in this region and are also a likely explanation for the secondary center of diversity. Our study indicates, however, that there is a higher concentration of species per unit area in the Philippines than anywhere in Indonesia, including Wallacea. The Philippine center of diversity is consistent with hypotheses that this area experienced numerous vicariant and island integration events and these hypotheses warrant further testing. Special attention to marine conservation efforts in the Philippines is justified because of the identification of it as an epicenter of biodiversity and evolution.