Endemic and Indo-Pacific plankton in the Mediterranean Sea: a study based on dinoflagellate records

Aim To investigate biogeographical patterns based on published dinoflagellate records from the Mediterranean and Black Seas, and to provide a tentative list of endemic and Indo‐Pacific dinoflagellates in the Mediterranean Sea. Location Mediterranean Sea, Black Sea. Methods Checklists of dinoflagellates of the Mediterranean and Black Seas were compared with worldwide literature records. Only species reported in the Indo‐Pacific Ocean or exclusively known in the Mediterranean Sea were selected for biogeographical analysis. Results Dinoflagellates in the Mediterranean Sea comprised c. 43% of the world marine species and c. 88% of the dinoflagellate genera. Species richness among the Mediterranean sub‐basins showed marked differences due to the less reliable records of unarmoured (athecate) and rare dinoflagellates. These differences disappeared when only the more easily identifiable taxa were considered. Of the 673 dinoflagellates cited in the Mediterranean, 87% were also reported in the Atlantic Ocean. Only 40 taxa (6% of the total) were considered to be potential Indo‐Pacific species. Most were reported from the Ligurian Sea (21), and only two species from the Levantine basin. The other 48 taxa (7% of total) were known exclusively from the Mediterranean Sea, mainly from the Ligurian Sea. Half of these taxa were reported by a single author. Main conclusions Substantial dinoflagellates species richness can be attributed, in part, to the historical tradition of taxonomic studies in the Mediterranean Sea. The list of species of both Indo‐Pacific and exclusively Mediterranean species included taxa of dubious taxonomic validity or that were insufficiently known. The exclusion of these questionable taxa revealed the near absence of endemic dinoflagellates in the Mediterranean Sea compared with macroscopic organisms. This could be related to: (1) continuous replenishment of the plankton populations by the inflow of Atlantic water through the Strait of Gibraltar, (2) the possibility that species introduced during the Pliocenic flooding after the Messinian salinity crisis have not had enough time to diverge from their Atlantic ancestors, and/or (3) the reliance on traditional taxonomy based on morphological characters, which precludes the detection of cryptic speciation.     

Discord in the family Sparidae (Teleostei): divergent phylogeographical patterns across the Atlantic-Mediterranean divide

The Strait of Gibraltar has been proposed to be the divide between two marine biogeographical regions, the Mediterranean Sea and the Northeast Atlantic. Intraspecific studies have shown, for several of the examined species, a reduction of gene flow between the two basins. The present study examines genetic variation at nuclear and mitochondrial loci in five marine teleost species belonging to the family Sparidae. Four samples for each species were analysed spanning the Northeast Atlantic and the Mediterranean. For all individuals 17 allozyme loci were scored and a combined single strand conformation polymorphism-sequencing approach was used to survey approximately 190 bp of the mitochondrial DNA (mtDNA) D-loop region. All five species share similar biological features. For three species, namely Lithognathus mormyrus, Spondyliosoma cantharus, and Dentex dentex, large mtDNA divergence was observed between Atlantic and Mediterranean samples. Little or no mtDNA differentiation was found in the other two species, Pagrus pagrus and Pagellus bogaraveo. Allozyme data revealed strong differentiation when comparing Atlantic and Mediterranean samples of L. mormyrus and D. dentex, moderate for P. pagrus, and no differentiation for P. bogaraveo and S. cantharus. These results provide evidence for a sharp phylogeographical break (sensu Avise) between the Atlantic and the Mediterranean for two (or possibly three) sparid species of the five investigated. At the same time, the obtained results for the other two species raise the question on which ecological/historical factors might have caused the observed discrepancy in the geographical distribution of genetic variation among otherwise biologically similar species.     

Systematics of the Deropristiidae Cable & Hunninen, 1942 (Trematoda) and biogeographical associations with sturgeons (Osteichthyes: Acipenseridae)

The 11 nominal species of the Deropristiidae, belonging to the genera Deropristis (three species), Pristicola (one species), Skrjabinopsolus (five species) and Cestrahelmins (two species) were re-evaluated for a phylogenetic and biogeographical analysis of the group. Skrjabinopsolus elongatus (Madhavi, 1974) (= S. indicus Gupta & Ahmad, 1976, S. kurotchkini Parukhin, 1976), S. sanyaensis Shen, 1990, Deropristis paurosoma Wang, 1989 and Cestrahelmins Fischthal, 1957, do not belong to the Deropristiidae. The genus Opisthodiplomonorchis Madhavi, 1974 is resurrected for its type-species, O. elongatus (= S. elongatus), and D. paurosoma is also transferred to this genus. Species of Opisthodiplomonorchis occur in polynemid fishes of the Indo-Pacific. Five nominal species thus comprise the Deropristiidae, i.e. S. armatus Ivanov in Ivanov and Mrygin, 1937, S. manteri (Cable, 1952), D. hispida (Abildgaard, 1819), D. inflata (Molin, 1859) and P. sturionis (Little, 1930), which corresponds to the original composition of the family. A comparison of Skrjabinopsolus from acipenserids in North America and Europe revealed variability in morphological characters considered diagnostic in the past (body size and position of the ovary and testes). Based on the morphology and biology, the two species of Skrjabinopsolus can be considered incipient species. A phylogenetic analysis of the redefined Deropristiidae indicates that Deropristis and Pristicola may form a monophyletic group with Skrjabinopsolus as the sister taxon. The biogeography of the Deropristiidae suggests an origin and distribution associated with the formation of the North Atlantic basin. Freshwater and marine/estuarine origins for the family are equally parsimonious possibilities. A freshwater origin can be traced at least to Cretaceous Laurasia followed by a drift-vicariance separation and subsequent association with North Atlantic drainages. Support for a marine ancestry of the Deropristiidae is indicated by the biogeography of its sister taxa (outgroups in this study) and of its hosts, and is also consistent with an Atlantic origin. The deropristiids evidently originated and speciated within the Acipenseridae in the Atlantic region, with a host switch into Atlantic Anguilla spp.     

Phylogeography of the planktonic chaetognath Sagitta setosa reveals isolation in European seas

Numerous planktonic species have disjunct distribution patterns in the world's oceans. However, it is unclear whether these are truly unconnected by gene flow, or whether they are composed of morphologically cryptic species. The marine planktonic chaetognath Sagitta setosa Müller has a discontinuous geographic distribution over the continental shelf in the northeastern Atlantic, Mediterranean Sea, and Black Sea. Morphological variation between these populations has been described, but overlaps and is therefore unsuitable to determine the degree of isolation between populations. To test whether disjunct populations are also genetically disjunct, we sequenced a 504-bp fragment of mitochondrial DNA comprising the cytochrome oxidase II region of 86 individuals. Sequences were highly variable; each represented a different haplotype. Within S. setosa, sequence divergence ranged from 0.2 to 8.1% and strong phylogeographic structure was found, with four main groups corresponding to the northeastern Atlantic, Mediterranean Sea (including Ligurian Sea, Tyrrhenian Sea and Gulf of Gabes), Adriatic Sea, and Black Sea. Two of these (Atlantic and Black Sea) were resolved as monophyletic clades, thus gene flow between disjunct populations of S. setosa has been extremely limited and lineage sorting has taken place. The deepest divergence was between Atlantic and Mediterranean/Black Sea populations followed by a split between Mediterranean and Black Sea populations. The Mediterranean/Black Sea clade comprised three groups, with the Adriatic Sea as the most likely sister clade of the Black Sea. These data are consistent with a colonization of the Black Sea from the Mediterranean. Furthermore, a possible cryptic species was found in the Black Sea with 23.1% sequence divergence from S. setosa. Two possibilities for the evolutionary origin of this species are proposed, namely, that it represents a relict species from the ancient Paratethys, or that it represents another chaetognath species that colonized the Black Sea more recently. Even though the exact timing of disjunction of S. setosa populations remains unclear, on the basis of the geological and paleoclimatic history of the European basins and our estimates of net nucleotide divergence, we suggest that disjunct populations arose through vicariance resulting from the cyclical changes in temperature and sea levels during the Pleistocene. We conclude that these populations have remained disjunct, not because of limited dispersal ability, but because of the inability to maintain viable populations in suboptimal, geographically intermediate areas.     

DNA barcoding of the northern Northeast Atlantic skates (Chondrichthyes,Rajiformes), with remarks on the widely distributed starry ray

The skate fauna in the northern Northeast (NE) Atlantic is poorly investigated, and misidentifications are common. Here, ‘DNA barcoding’ was used to analyse 105 specimens of 15 species previously reported from the area to investigate the occurrence of species. Of these 15 species, three were new to the region and confirmed with voucher specimens. Three previously reported taxa were not obtained from the study area, providing a total number of 12 skate species for the northern NE Atlantic. Only one specimen of the critically endangered Dipturus batis complex was found. It occurs frequently in the literature and commercial fisheries catch records, and we argue that the vast majority of these are misidentifications. Due to striking differences in Amblyraja radiata life history parameters across the North Atlantic, cryptic species diversity has previously been suspected. A total of 80 A. radiata cytochrome c oxidase subunit I sequences from across the North Atlantic were sampled, and the highest fixation index (F_ST) was found when maximising geographical distance (F_ST = 0.133). A lower index was found when grouped according to life history (F_ST = 0.067). These results are not strongly supportive for the occurrence of cryptic species.     

Climate change opens new frontiers for marine species in the Arctic: Current trends and future invasion risks

Climate change and increased anthropogenic activities are expected to elevate the potential of introducing nonindigenous species (NIS) into the Arctic. Yet, the knowledge base needed to identify gaps and priorities for NIS research and management is limited. Here, we reviewed primary introduction events to each ecoregion of the marine Arctic realm to identify temporal and spatial patterns, likely source regions of NIS, and the putative introduction pathways. We included 54 introduction events representing 34 unique NIS. The rate of NIS discovery ranged from zero to four species per year between 1960 and 2015. The Iceland Shelf had the greatest number of introduction events (n = 14), followed by the Barents Sea (n = 11), and the Norwegian Sea (n = 11). Sixteen of the 54 introduction records had no known origins. The majority of those with known source regions were attributed to the Northeast Atlantic and the Northwest Pacific, 19 and 14 records, respectively. Some introduction events were attributed to multiple possible pathways. For these introductions, vessels transferred the greatest number of aquatic NIS (39%) to the Arctic, followed by natural spread (30%) and aquaculture activities (25%). Similar trends were found for introductions attributed to a single pathway. The phyla Arthropoda and Ochrophyta had the highest number of recorded introduction events, with 19 and 12 records, respectively. Recommendations including vector management, horizon scanning, early detection, rapid response, and a pan‐Arctic biodiversity inventory are considered in this paper. Our study provides a comprehensive record of primary introductions of NIS for marine environments in the circumpolar Arctic and identifies knowledge gaps and opportunities for NIS research and management. Ecosystems worldwide will face dramatic changes in the coming decades due to global change. Our findings contribute to the knowledge base needed to address two aspects of global change—invasive species and climate change.     

A new species of Fauveliopsidae (Annelida) from the North Sea

A new species of the genus Laubieriopsis Petersen, 2000 is described based on 28 specimens collected in the north-east part of the North Sea. It is characterized by fixed number of chaetigers (22), paired genital papillae, bidentate neurochaeta of chaetigers 1-4, the absence of acicular chaetae on chaetigers 5-21 and, on the last chaetiger, one acicular and three capillary chaetae enlarged and directed backward. The present study brings the number of known species of Laubieriopsis to five and the number of Northeast Atlantic species of this genus to two.     

Cryptic speciation and paraphyly in the cosmopolitan bryozoan Electra pilosa--impact of the Tethys closing on species evolution

Cosmopolitan nature of the marine bryozoan Electra pilosa was studied to clarify geographic structure and to outline evolution and phylogeography of the species. Several local populations from the Northeast Atlantic (North Sea and Baltic Sea), Arctic (Barents Sea and White Sea) and Indo-West Pacific (New Zealand) were compared. In addition, we examined the closely related species E. posidoniae from the Mediterranean Sea. Phylogenetic analysis based on both 16S and 18S rDNA indicate that the Indo-West Pacific E. pilosa is a sister species to the Atlantic-Mediterranean clade, with the latter including the species E. posidoniae and the Atlantic population of E. pilosa. The topology of the phylogenetic tree leads us to conclude that E. pilosa is a paraphyletic species group relative to E. posidoniae, and a molecular dating of its divergence is consistent to geologic events associated with the closure of the Tethys Sea.     

Biogeography of the marine birds of a confined sea, the Mediterranean

Aim The Mediterranean sea is a winter productive oligotrophic basin where Atlantic water replaces water lost through evaporation, this influx being a major source of productivity and fertility. The long coastlines and the large number of islands cause high oceanographic heterogeneity. Moreover, during its geological history, it has dried out several times. So we describe the consequences of these particular features on species richness, distribution, and breeding ecology of marine birds. Location The Mediterranean sea (including the Black Sea and the Sea of Azov) communicates with the Atlantic Ocean only through a 14 km wide channel (Straits of Gibraltar), and since 1869, with the Red Sea through the Suez Canal. Methods The Mediterranean was subdivided into different areas, according to physical oceanographic entities and productivity, linked to numbers and distribution of both breeding and wintering marine birds (defined as species strongly dependent on marine resources, breeding only on islands and/or the coastline). Results The total marine bird biomass, and species diversity, are lower in the Mediterranean than in the near Atlantic. The eastern Mediterranean, with lowest primary productivity, contains fewer marine bird taxa than the more productive western part. Taxa which mainly occur in the western and southern parts of the Mediterranean migrate through the Straits of Gibraltar to winter in the southern Atlantic, while those inhabiting the northern and eastern parts are sedentary, as a result of differences in species composition. Northern coastal basin communities (i.e. the Tyrrhenian and the Balearic Seas), are composed of less pelagic, and earlier breeding species, that rear chicks during the productive season. These latter taxa are actually the most typical Mediterranean taxa, in terms of endemism. Main conclusions The Mediterranean marine bird community is not tropical, but rather, shows the highest affinity with the Atlantic temperate community. Its level of endemism is however high and comparable to other confined basins such as the Red Sea.     

Phytogeography of the liverwort flora of the Atlantic Forest of southeastern Brazil

Abstract

This work analyzes the phytogeographic patterns of the liverwort flora of the Atlantic Forest of the Rio de Janeiro State, south-eastern Brazil. The analysis was based on inventories made in fragments of Atlantic Forest in the state, collections from the RB herbarium, and information from the checklist and database of the bryoflora of Rio de Janeiro. The phytogeographic pattern for each taxon was characterized based on its current distribution. Three hundred and sixty liverwort taxa are recognized for Rio de Janeiro. The liverwort flora varies along an altitudinal gradient within the Atlantic Forest, with the montane belt having the greatest species richness (238), the highest number of exclusive taxa (63) and the greatest number of endemic species (23). The predominant phytogeographic element is of neotropical species (49%), followed by disjunct liverworts (18%). Forty-one taxa (11%) are endemic to the country, of which 34 are restricted to the Atlantic Forest. In the lowland and submontane formations species are wide-ranging, whereas the montane and upper montane formations are characterized by endemic species or those disjunct with the Andes. The liverwort flora emphasizes the importance of the fragments of Atlantic Forest in Rio de Janeiro as a centre of diversity and endemism, supporting 50% of the total liverwort species known in Brazil, 72% of those recorded from Atlantic Forest and 55% of the endemic species of the country. Species with an Afro-American and Andean disjunction make up a characteristic part of the liverwort flora, probably reflecting the effects of long-distance dispersal by air currents, migration over land before the breakup of the continents and climatic similarities between the high-altitude grasslands and the northern Andes.     

Mayflies (Ephemeroptera) from Reserva Ecológica Michelin,Bahia, Brazil

New records and distributional notes are provided for Reserva Ecológica Michelin, an Atlantic Forest fragment near the southern coast of Bahia State, Brazil. Two families, four genera and five species are recorded for the first time in Bahia State. Additionally, one family, two genera and three species are also recorded for the first time in the Northeast Region of Brazil, resulting in nine families, 48 genera and 96 species recorded to this region. Amongst the recorded species, Hermanella mazama (Nascimento, Mariano, and Salles, 2012) has been classified as an endangered species on the official Brazilian red list.     

Multifaceted assessment of species validity in the Dasymutilla bioculata species group (Hymenoptera: Mutillidae)

This study examines the validity of the ten species and eight subspecies composing the Dasymutilla bioculata species group. Four lines of evidence are examined: morphological data derived from both sexes; behavioural data derived from the study of mating pairs; geographic distribution; and molecular data derived from the internal transcribed spacers 1 and 2 of the nuclear ribosomal RNA cistron (ITS1 and ITS2). Morphological studies reveal that none of the taxa in question can be consistently diagnosed by any synapomorphies or unique combinations of characters. Mating studies reveal that males of single nominal taxa are attracted to females of multiple nominal taxa, and that females of single nominal taxa attract multiple males. None of the nominal taxa are geographically isolated from the others. Genetic distances between these taxa are significantly lower than those seen in interspecific comparisons of other Dasymutilla species. Based on this evidence, we infer that the taxa in question share a recent common ancestor, and cannot be adequately differentiated using any of the available data sources. Therefore, employing the phylogenetic species concept, Dasymutilla bimaculata Manley & Pitts, Dasymutilla chiron chiron (Blake), Dasymutilla chiron ursula (Cresson), Dasymutilla creusa creusa (Cresson), Dasymutilla creusa bellona (Cresson), Dasymutilla lepeletierii (Fox), Dasymutilla medea (Cresson), Dasymutilla melanippe melanippe Mickel, Dasymutilla melanippe conformis Mickel, Dasymutilla praegrandis praegrandis Mickel, Dasymutilla praegrandis russata Mickel, Dasymutilla pyrrhus (Fox) and Dasymutilla sulcatulla Mickel must be considered junior synonyms of Dasymutilla bioculata (Cresson). We also discuss the identification of this species, as well as subspecific relationships and species‐group implications.     

Phylogeography of Ophioblennius: the role of ocean currents and geography in reef fish evolution

Many tropical reef fishes are divided into Atlantic and East Pacific taxa, placing similar species in two very different biogeographic regimes. The tropical Atlantic is a closed ocean basin with relatively stable currents, whereas the East Pacific is an open basin with unstable oceanic circulation. To assess how evolutionary processes are influenced by these differences in oceanography and geography, we analyze a 630-bp region of mitochondrial cytochrome b from 171 individuals in the blenniid genus Ophioblennius. Our results demonstrate deep genetic structuring in the Atlantic species, O. atlanticus, corresponding to recognized biogeographic provinces, with divergences of d = 5.2-12.7% among the Caribbean, Brazilian, St. Helena/Ascension Island, Gulf of Guinea, and Azores/Cape Verde regions. The Atlantic phylogeny is consistent with Pliocene dispersal from the western to eastern Atlantic, and the depth of these separations (along with prior morphological comparisons) may indicate previously unrecognized species. The eastern Pacific species, O. steindachneri, is characterized by markedly less structure than O. atlanticus, with shallow mitochondrial DNA lineages (dmax = 2.7%) and haplotype frequency shifts between locations in the Sea of Cortez, Pacific Panama, Clipperton Island, and the Galapagos Islands. No concordance between genetic structure and biogeographic provinces was found for O. steincdachneri. We attribute the phylogeographic pattern in O. atlanticus to dispersal during the reorganization of Atlantic circulation patterns that accompanied the shoaling of the Isthmus of Panama. The low degree of structure in the eastern Pacific is probably due to unstable circulation and linkage to the larger Pacific Ocean basin. The contrast in genetic signatures between Atlantic and eastern Pacific blennies demonstrates how differences in geology and oceanography have influenced evolutionary radiations within each region.     

Plant diversity of Hyrcanian relict forests: An annotated checklist,chorology and threat categories of endemic and near endemic vascular plant speciesOA

In this paper a critical annotated checklist of 256 endemic and near endemic species belonging to 152 genera and 50 families of flowering plants known from Hyrcanian relict forests is presented. Distribution maps of taxa, elevational range, number of known records, chorotypes, life forms, IUCN threat categories and habitat types are also provided. The chorotypes are categorized into eight main patterns: 1) the Omni-Hyrcanian pattern(OH), 2) West Hyrcanian pattern(WH), 3) Manjil-Rudbar pattern(MR...     

The deep-water macroalgal community of the East Florida continental shelf (USA)

The deep-water macroalgal community of the continental shelf off the east coast of Florida was sampled by lock-out divers from two research submersibles as part of the most detailed year-round study of a macroalgal community extending below routine SCUBA depths. A total of 208 taxa (excluding crustose corallines) were recorded; of these, 42 (20.2%), 19 (9.1%), and 147 (70.7%) belonged to the Chlorophyta, Phaeophyta, and Rhodophyta, respectively. Taxonomic diversity was maximal during late spring and summer and minimal during late fall and winter. The number of reproductive taxa closely followed the number of taxa present; when reproductive frequency was expressed as a percentage of the species present during each month, two peaks (January and August) were observed. Most perennial species had considerable depth ranges, with the greatest number of taxa observed from 31 to 40 m in depth. Although most of the taxa present also grow in shallow water (i.e. <10 m), there were some species whose distribution is limited to deeper water. The latter are strongly dominated by rhodophytes. This community has a strong tropical affinity, but over half the taxa occur in warm-temperate areas. Forty-two new records (20% of the taxa identified) for Florida were listed; this includes 15 taxa which previously had been considered distributional disjuncts in this area. The phaeophyteHalopteris filicina is a new addition to the flora of the western Atlantic. Although more studies are needed, it appears that the deep-water flora may be relatively continuous over a large portion of the tropical and subtropical western North Atlantic. The traditional practice of considering Cape Canaveral as a biogeographical boundary may only be appropriate for shallow water. This study demonstrates the need for additional floristic work on macroalgal communities, especially from deep water, before more detailed biogeographical analyses can be performed and suggests that deep-water species could be important in experimental approaches to macroalgal biogeography.     

An annotated checklist of dinoflagellates in the Black Sea

An annotated checklist of free-living dinoflagellates (Dinophyceae) of the Black Sea, based on literature records, is reported and compared to the Mediterranean Sea and world oceans. Toxic species and/or responsible of harmful algal blooms (HAB) are marked in the checklist. From the 267 species (54 genera) listed nearly all taxa can be considered as cosmopolitan and no species as endemic. Several typically Arctic-boreal species (non recorded from the Mediterranean Sea) are reported from the Black Sea. The taxonomy and the biogeography of the taxa are discussed.     

Historical climate modelling predicts patterns of current biodiversity in the Brazilian Atlantic forest

Aim We aim to propose validated, spatially explicit hypotheses for the late Quaternary distribution of the Brazilian Atlantic forest, and thereby provide a framework for integrating analyses of species and genetic diversity in the region. Location The Atlantic forest, stretching along the Brazilian coast. Methods We model the spatial range of the forest under three climatic scenarios (current climate, 6000 and 21,000 years ago) with BIOCLIM and MAXENT. Historically stable areas or refugia are identified as the set of grid cells for which forest presence is inferred in all models and time projections. To validate inferred refugia, we test whether our models are matched by the current distribution of the forest and by fossil pollen data. We then investigate whether the location of inferred forest refugia is consistent with current patterns of species endemism and existing phylogeographical data. Results Forest models agree with pollen records and predict a large area of historical forest stability in the central corridor (Bahia), as well as a smaller refuge (Pernambuco) along the Brazilian coast, matching current centres of endemism in multiple taxa and mtDNA diversity patterns in a subset of the species examined. Less historical stability is predicted in coastal areas south of the Doce river, which agrees with most phylogeographical studies in that region. Yet some widely distributed taxa show high endemism in the southern Atlantic forest. This may be due to limitations of the modelling approach, differences in ecology and dispersal capability, historical processes not contemplated by the current study or inadequacy of the available test data sets. Main conclusions Palaeoclimatic models predict the presence of historical forest refugia in the Atlantic rain forest and suggest spatial variation in persistence of forests through the Pleistocene, predicting patterns of biodiversity in several local taxa. The results point to the need for further studies to document genetic and species endemism in the relatively poorly known and highly impacted areas of Atlantic rain forests of north‐eastern Brazil.     

New records of Malaysian marine algae

Checklists of the marine algae of Malaysia have been published. The last checklist included the marine algae of Singapore. The checklist recorded 212 taxa for the region. This paper lists an additional 7 taxa of Chlorophyta, 18 taxa of Rhodophyta and 5 taxa of Phaeophyta, which had been left out of the last checklist. These include marine algae from Pulau Pinang, Pulau Redang and Pulau Sibu. In addition, new records of Cyanophyta (2 species), Chlorophyta (4 species), Rhodophyta (10 species) and Phaeophyta (3 species) are reported.