scholarly journals Functional diversity of microboring Ostreobium algae isolated from corals

2020 ◽  
Author(s):  
A. Massé ◽  
A. Tribollet ◽  
T. Meziane ◽  
M.L. Bourguet-Kondracki ◽  
C. Yéprémian ◽  
...  
Keyword(s):  
Trophic Ecology ◽  
Carbon Fixation ◽  
Sequence Divergence ◽  
Coral Host ◽  
Free Living ◽  
Isotope Tracer ◽  
Bleached Coral ◽  
Marine Carbonate ◽  
Coral Holobiont ◽  
The Family

AbstractThe filamentous chlorophyte Ostreobium sp. dominates shallow marine carbonate microboring communities, and is one of the major agents of reef bioerosion. While its large genetic diversity has emerged, its physiology remains little known, with unexplored relationship between genotypes and phenotypes (endolithic versus free-living growth forms). Here, we isolated 9 strains affiliated to 2 lineages of Ostreobium (>8% sequence divergence of the plastid gene rbcL), one of which was assigned to the family Odoaceae, from the fast-growing coral host Pocillopora acuta Lamarck 1816. Free-living isolates maintained their bioerosive potential, colonizing pre-bleached coral carbonate skeletons. We compared phenotypes, highlighting shifts in pigment and fatty acid compositions, carbon to nitrogen ratios and stable isotope compositions (δ13C and δ15N). Our data show a pattern of higher chlorophyll b and lower arachidonic acid (20:4ω6) content in endolithic versus free-living Ostreobium. Photosynthetic carbon fixation and nitrate uptake, quantified via 8h pulse-labeling with 13C-bicarbonate and 15N-nitrate, showed lower isotopic enrichment in endolithic compared to free-living filaments. Our results highlight the functional plasticity of Ostreobium phenotypes. The isotope tracer approach opens the way to further study the biogeochemical cycling and trophic ecology of these cryptic algae at coral holobiont and reef scales.

scholarly journals Transcriptome landscape of a thermal-tolerant coral endosymbiont reveals molecular signatures of symbiosis and dysbiosis

2018 ◽  
Author(s):  
Anthony J. Bellantuono ◽  
Katherine E. Dougan ◽  
Camila Granados-Cifuentes ◽  
Mauricio Rodriguez-Lanetty
Keyword(s):  
Heat Tolerance ◽  
Transcriptional Activity ◽  
Transcriptional Response ◽  
Coral Host ◽  
Molecular Signatures ◽  
Free Living ◽  
Stable Temperature ◽  
Stable Conditions ◽  
The Family ◽  
Stress Environment

AbstractWarming oceans disrupt the critical endosymbiosis between corals and their photosynthetic dinoflagellate endosymbionts of the family Symbiodiniaceae. Durusdinium trenchii is a heat-tolerant species of Symbiodiniaceae and enhances survival of its coral host, but the basis for tolerance is largely unknown. To identify the underpinnings of heat tolerance and symbiosis, we compared the in hospite and free-living transcriptomes of D. trenchii under stable temperature conditions and acute hyperthermal stress. We discovered that under stable conditions, in hospite cells exhibit lower transcriptional activity than free-living counterparts, suggesting the shutdown of genes uniquely required for a free-living lifestyle. However, under hyperthermal stress the transcriptional response was larger in hospite, indicating an exacerbated stress environment within the host cell. Significantly, we unraveled the molecular signatures of symbiont heat tolerance within the host, which is a critical step to enable the development of engineered endosymbionts as a tool for restoration of coral reefs.

Two new freshwater planarian species (Platyhelminthes: Tricladida: Dugesiidae) partially sympatric in Argentinean Patagonia

2021 ◽  
pp. 269-278
Author(s):  
M. Lenguas Francavilla ◽  
L. Negrete ◽  
A. Martínez-Aquino ◽  
C. Damborenea ◽  
F. Brusa
Keyword(s):  
Phylogenetic Analysis ◽  
Molecular Data ◽  
Neotropical Region ◽  
Free Living ◽  
Mitochondrial Coi ◽  
Argentinean Patagonia ◽  
The Family ◽  
Taxonomic Approach ◽  
Morphological And Molecular Data ◽  
Endemic Flora

Girardia Ball, 1974 is the most diverse and widely distributed genus of the family Dugesiidae (Platyhelminthes: Continenticola) in the Neotropical region. Seven out of the 52 species of the genus are known for Argentina. The Somuncurá Plateau is a region in northern Patagonia with several endemic flora and fauna, but little is known about the free-living Platyhelminthes. We describe two new species of Girardia partially inhabiting in sympatry in the Somuncurá Plateau: Girardia somuncura sp. nov. and Girardia tomasi sp. nov. The identification criteria that we followed was an integrative taxonomic approach based on morphological and molecular data. Thus, we used anatomical features focused on the reproductive system, together with a phylogenetic analysis, using a mitochondrial (COI barcode region) genetic marker. This study is the first phylogenetic analysis of the genus Girardia in which we include the southernmost representatives of America here described, thus making it possible to incorporate them in global phylogenies.

scholarly journals Savitreea pentosicarens gen. nov., sp. nov., a yeast species in the family Saccharomycetaceae isolated from a grease trap

2020 ◽  
Vol 70 (11) ◽  
pp. 5665-5670
Author(s):  
Varunya Sakpuntoon ◽  
Jirameth Angchuan ◽  
Chanita Boonmak ◽  
Pannida Khunnamwong ◽  
Noémie Jacques ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Yeast Species ◽  
Sequence Divergence ◽  
Its Region ◽  
Rrna Gene ◽  
Nucleotide Substitutions ◽  
D2 Domain ◽  
The Family ◽  
Lsu Rrna Gene ◽  
Lsu Rrna

Two strains (DMKU-GTCP10-8 and CLIB 1740) representing a novel anamorphic yeast species were isolated from a grease sample collected from a grease trap in Thailand and from an unidentified fungus collected in French Guiana, respectively. On the basis of phylogenetic analysis based on the combined D1/D2 domain of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, Lachancea fermentati CBS 707T was the closely related species with 12.8 % sequence divergence (70 nucleotide substitutions and three gaps in 571 nucleotides) and 28.1 % sequence divergence (93 nucleotide substitutions and 90 gaps in 651 nucleotides) in the D1/D2 domain of the LSU rRNA gene and the ITS region, respectively. Phylogenetic analysis based on the concatenated sequences of the five genes including the small subunit rRNA gene, the D1/D2 domain of the LSU rRNA gene, the ITS region, translation elongation factor-1 alpha (TEF1) and RNA polymerase II subunit 2 (RPB2) genes confirmed that the two strains (DMKU-GTCP10-8 and CLIB 1740) were well-separated from other described yeast genera in Saccharomycetaceae. Hence, Savitreea pentosicarens gen. nov., sp. nov. is proposed to accommodate these two strains as members of the family Saccharomycetaceae. The holotype is S. pentosicarens DMKU-GTCP10-8T (ex-type strain TBRC 12159=PYCC 8490; MycoBank number 835044).

How long do Tydeidae live?

Zoosymposia ◽  
2021 ◽  
Vol 20 ◽  
Author(s):  
LIANA JOHANN ◽  
GUILHERME LIBERATO DA SILVA
Keyword(s):  
Life History ◽  
Feeding Habits ◽  
Free Living ◽  
The Family ◽  
The World

The family Tydeidae consists of small, free-living, soft-bodied mites with a diversity of feeding habits, including phytophages, pollen feeders and even predators, but the majority are scavengers or fungivores. Approximately 330 species in 30 genera have been described from throughout the world, but only a few species (<1% of all species) have been studied for their life history. This review provides a survey of their life history with a focus on their lifespan.

Biogeography and Host Usage of Coral-Associated Crustaceans: Barnacles, Copepods, and Gall Crabs as Model Organisms

2020 ◽  
pp. 183-215
Author(s):  
Benny K. K. Chan ◽  
Kingsley J. H. Wong ◽  
Yu-Rong Cheng
Keyword(s):  
Deep Sea ◽  
Model Organisms ◽  
Coral Host ◽  
West Pacific ◽  
Pacific Waters ◽  
Extant Species ◽  
The Family ◽  
The Caribbean ◽  
Diverse Groups ◽  
Gall Crabs

Most of the diverse groups of crustaceans associated with scleractinian and fire corals form symbiotic relationship with their coral hosts. Coral-associated barnacles include species from the orders Acrothoracica and Thoracica. Most of the coral-associated barnacles belong to the family Pyrgomatidae in Thoracica. Within Pyrgomatidae, the subfamily Ceratoconchinae contains mostly extant species and is present from Florida through the Caribbean to Brazilian waters. The subfamily Megatrematinae has lower species diversity and has a cosmopolitan distribution (except the Eastern Pacific). The Pyrgomatinae are the most species-rich subfamily and distributed only in Indo-West Pacific waters. Host usage of pyrgomatinid barnacles varies spatially, probably related to coral host diversity. Copepods are the most common and most abundant coral-associated crustaceans, often associated with scleractinian, gorgonian, and alcyonacean corals. More than 90% of coral-associated copepods are endemic to the Indo-West Pacific. In contrast, only a few species (<10%) have been discovered from the Atlantic due to several historical perturbations reducing the diversity of their coral hosts. The communities of coral-associated copepods thus show dramatic differences between geographic regions, notably between the Indian, Pacific, and Atlantic Oceans. Brachyurans of the family Cryptochiridae (gall crabs) are obligate associates or parasites, of scleractinian coral hosts in tropical and subtropical seas, being a monophyletic group of only 52 species, from the intertidal to the deep sea (to 512 m) habitats with most (46) recorded in the seas of the tropical Indo-West Pacific and none being cosmopolitan. Atlantic species of Cryptochiridae, apparently not phylogenetically related, display less strict host specificity than their Indo-West Pacific counterparts. Current phylogenetic understandings of the group remain preliminary, while one consistent Indo-West Pacific clade reflects rapid species diversification during the last ~15 million years.

scholarly journals Distinct nitrogen cycling and steep chemical gradients in Trichodesmium colonies

2019 ◽  
Vol 14 (2) ◽  
pp. 399-412 ◽  
Author(s):  
Isabell Klawonn ◽  
Meri J. Eichner ◽  
Samuel T. Wilson ◽  
Nasrollah Moradi ◽  
Bo Thamdrup ◽  
...  
Keyword(s):  
Carbon Fixation ◽  
Nitrate Concentration ◽  
Concentration Gradients ◽  
Ambient Seawater ◽  
N Transformations ◽  
Isotope Tracer ◽  
Chemical Gradients ◽  
Nitrate Consumption ◽  
N Compounds ◽  
Numeric Modelling

Abstract Trichodesmium is an important dinitrogen (N2)-fixing cyanobacterium in marine ecosystems. Recent nucleic acid analyses indicate that Trichodesmium colonies with their diverse epibionts support various nitrogen (N) transformations beyond N2 fixation. However, rates of these transformations and concentration gradients of N compounds in Trichodesmium colonies remain largely unresolved. We combined isotope-tracer incubations, micro-profiling and numeric modelling to explore carbon fixation, N cycling processes as well as oxygen, ammonium and nitrate concentration gradients in individual field-sampled Trichodesmium colonies. Colonies were net-autotrophic, with carbon and N2 fixation occurring mostly during the day. Ten percent of the fixed N was released as ammonium after 12-h incubations. Nitrification was not detectable but nitrate consumption was high when nitrate was added. The consumed nitrate was partly reduced to ammonium, while denitrification was insignificant. Thus, the potential N transformation network was characterised by fixed N gain and recycling processes rather than denitrification. Oxygen concentrations within colonies were ~60–200% air-saturation. Moreover, our modelling predicted steep concentration gradients, with up to 6-fold higher ammonium concentrations, and nitrate depletion in the colony centre compared to the ambient seawater. These gradients created a chemically heterogeneous microenvironment, presumably facilitating diverse microbial metabolisms in millimetre-sized Trichodesmium colonies.

scholarly journals Phylogenetic position and taxonomy of Cycloseris explanulata and C. wellsi (Scleractinia: Fungiidae): lost mushroom corals find their way home

2012 ◽  
Vol 81 (3) ◽  
pp. 125-146 ◽  
Author(s):  
Francesca Benzoni ◽  
Roberto Arrigoni ◽  
Fabrizio Stefani ◽  
Bastian T. Reijnen ◽  
Simone Montano ◽  
...  
Keyword(s):  
Molecular Study ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Distribution Data ◽  
Data Sets ◽  
Free Living ◽  
New Findings ◽  
The Family ◽  
Ecological Implications ◽  
History Of

The scleractinian species Psammocora explanulata and Coscinaraea wellsi were originally classified in the family Siderastreidae, but in a recent morpho-molecular study it appeared that they are more closely related to each other and to the Fungiidae than to any siderastreid taxon. A subsequent morpho-molecular study of the Fungiidae provided new insights regarding the phylogenetic relationships within that family. In the present study existing molecular data sets of both families were analyzed jointly with those of new specimens and sequences of P. explanulata and C. wellsi. The results indicate that both species actually belong to the Cycloseris clade within the family Fungiidae. A reappraisal of their morphologic characters based on museum specimens and recently collected material substantiate the molecular results. Consequently, they are renamed Cycloseris explanulata and C. wellsi. They are polystomatous and encrusting like C. mokai, another species recently added to the genus, whereas all Cycloseris species were initially thought to be monostomatous and free-living. In the light of the new findings, the taxonomy and distribution data of C. explanulata and C. wellsi have been updated and revised. Finally, the ecological implications of the evolutionary history of the three encrusting polystomatous Cycloseris species and their free-living monostomatous congeners are discussed.

High cryptic diversity in the kleptoparasitic genus Hyalorisia Dall, 1889 (Littorinimorpha: Capulidae) with the description of nine new species from the Indo-West Pacific

2020 ◽  
Vol 86 (4) ◽  
pp. 401-421 ◽  
Author(s):  
Giulia Fassio ◽  
Valeria Russini ◽  
Barbara Buge ◽  
Stefano Schiaparelli ◽  
Maria Vittoria Modica ◽  
...  
Keyword(s):  
Trophic Ecology ◽  
Molecular Data ◽  
Sympatric Species ◽  
Water Current ◽  
Phylogenetic Position ◽  
Nominal Species ◽  
West Pacific ◽  
Allopatric Species ◽  
Wide Range ◽  
The Family

ABSTRACT Species in the family Capulidae (Littorinimorpha: Capuloidea) display a wide range of shell morphologies. Several species are known to live in association with other benthic invertebrates—mostly bivalves and sabellid worms, but also other gastropods—and are believed to be kleptoparasitic filter feeders that take advantage of the water current produced by the host. This peculiar trophic ecology, implying a sedentary lifestyle, has resulted in highly convergent shell forms. This is particularly true for the genus Hyalorisia Dall, 1889, which occurs in deep water in the Caribbean and Indo-West Pacific provinces, with two nominal species recognized so far. Combining morphological, ecological and molecular data, we assessed the diversity of the genus, its phylogenetic position inside the family and its association with its bivalve host, the genus Propeamussium de Gregorio, 1884 (Pectinoidea), resulting in the description of nine new cryptic species. When sympatric, species of Hyalorisia are associated with different host species, but the same species of Propeamussium may be the host of several allopatric species of Hyalorisia.

Taxonomic revision of the genus Gephyrellula Strand, 1932 (Arachnida, Araneae, Philodromidae)

Zootaxa ◽  
2018 ◽  
Vol 4527 (3) ◽  
pp. 381 ◽  
Author(s):  
FABRICIO H. SANTOS ◽  
CRISTINA A. RHEIMS
Keyword(s):  
Geographical Distribution ◽  
Type Species ◽  
Taxonomic Revision ◽  
Junior Synonym ◽  
Distribution Map ◽  
Free Living ◽  
The Family ◽  
Family Level

Spiders of the family Philodromidae are free-living active predators, with laterigrade legs, eyes without tubercles, two tarsal claws and claw tufts. Although very common in zoological collections, their systematics is poorly known, especially in the Neotropics, and their specimens are usually identified only at family level. In this paper, the genus Gephyrellula Strand, 1932 is revised and the type species, G. violacea (Mello-Leitão, 1918) is redescribed and illustrated. Gephyrellula paulistana (Soares, 1943) is considered a junior synonym of G. violacea and thus, the genus becomes monotypic. In addition, the geographical distribution is extended and an updated distribution map is provided. 

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