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1.
Proc Natl Acad Sci U S A ; 121(14): e2311597121, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38527199

RESUMEN

Warmer temperatures and higher sea level than today characterized the Last Interglacial interval [Pleistocene, 128 to 116 thousand years ago (ka)]. This period is a remarkable deep-time analog for temperature and sea-level conditions as projected for 2100 AD, yet there has been no evidence of fossil assemblages in the equatorial Atlantic. Here, we report foraminifer, metazoan (mollusks, bony fish, bryozoans, decapods, and sharks among others), and plant communities of coastal tropical marine and mangrove affinities, dating precisely from a ca. 130 to 115 ka time interval near the Equator, at Kourou, in French Guiana. These communities include ca. 230 recent species, some being endangered today and/or first recorded as fossils. The hyperdiverse Kourou mollusk assemblage suggests stronger affinities between Guianese and Caribbean coastal waters by the Last Interglacial than today, questioning the structuring role of the Amazon Plume on tropical Western Atlantic communities at the time. Grassland-dominated pollen, phytoliths, and charcoals from younger deposits in the same sections attest to a marine retreat and dryer conditions during the onset of the last glacial (ca. 110 to 50 ka), with a savanna-dominated landscape and episodes of fire. Charcoals from the last millennia suggest human presence in a mosaic of modern-like continental habitats. Our results provide key information about the ecology and biogeography of pristine Pleistocene tropical coastal ecosystems, especially relevant regarding the-widely anthropogenic-ongoing global warming.


Asunto(s)
Ecosistema , Moluscos , Humanos , Animales , Guyana Francesa , Plantas , Polen , Fósiles
2.
Mol Phylogenet Evol ; 191: 107994, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38113961

RESUMEN

Deep-water coral reefs are found worldwide and harbor biodiversity levels that are comparable to their shallow-water counterparts. However, the genetic diversity and population structure of deep-water species remain poorly explored, and historical taxonomical issues still need to be resolved. Here we used microsatellite markers as well as ultraconserved elements (UCE) and exons to shed light on the population structure, genetic diversity, and phylogenetic position of the genus Madrepora, which contains M. oculata, one of the most widespread scleractinian species. Population structure of 107 samples from three Southwestern Atlantic sedimentary basins revealed the occurrence of a cryptic species, herein named M. piresae sp. nov. (authored by Kitahara, Capel and Zilberberg), which can be found in sympatry with M. oculata. Phylogeny reconstructions based on 134 UCEs and exon regions corroborated the population genetic data, with the recovery of two well-supported groups, and reinforced the polyphyly of the family Oculinidae. In order to better accommodate the genus Madrepora, while reducing taxonomical confusion associated with the name Madreporidae, we propose the monogeneric family Bathyporidae fam. nov. (authored by Kitahara, Capel, Zilberberg and Cairns). Our findings advance the knowledge on the widespread deep-water genus Madrepora, resolve a long-standing question regarding the phylogenetic position of the genus, and highlight the need of a worldwide review of the genus.


Asunto(s)
Antozoos , Agua , Animales , Filogenia , Arrecifes de Coral , Biodiversidad
3.
BMC Evol Biol ; 18(1): 66, 2018 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-29716521

RESUMEN

BACKGROUND: Previous phylogenetic analyses of primnoid octocorals utilizing morphological or molecular data have each recovered evolutionary relationships among genera that are largely incongruent with each other, with some exceptions. In an effort to reconcile molecular-based phylogenies with morphological characters, phylogenetic reconstructions were performed with 33 of 43 primnoid genera using four loci (mtMutS, COI, 28S and 18S), and ancestral state reconstructions were performed using 9 taxonomically relevant characters. In addition, an updated illustrated key to the current 48 genus-level (43 genera, 5 subgenera) primnoids is presented. RESULTS: Ancestral state reconstruction recovered the ancestral colony shape of primnoids as dichotomous planar. Convergence was detected among all 9 characters, and reversals to the character state of the common ancestor occurred in 4 characters. However, some characters were found to be informative. For example, the weak ascus scale of Metafannyella is not likely homologous to the ascus scales of Onogorgia and Fannyella, and the monophyly of two subgenera within Thouarella, which contain polyps in either whorls or an isolated arrangement, was supported. Phylogenetic analyses were generally consistent with previous studies, and resulted in the synonymy of one genus and a subgenus, the elevation of two subgenera, and the transfer of two species back to an original genus. For example, body wall ornamentation of Fanellia was re-evaluated, indicating a synonymy with Callogorgia; the utility of polyp arrangement for the subgenus Plumarella (Dicholaphis) was not supported, and is synonymized with the nominate subgenus Plumarella (Plumarella); the subgenera Plumarella (Faxiella) and Plumarella (Verticillata) are raised to generic status; and the two Plumarella species (P. diadema and P. undulata) are transferred back to Thouarella based on the homology of their marginal scales. CONCLUSIONS: Altogether, and similar to other octocorallian groups, these results indicate that many of the morphological characters examined among primnoids, particularly colony morphology, are labile and exhibit complex evolutionary histories. However, some morphological characters such as coordination of polyps, presence of the ascus body wall scale, number of rows of body wall scales, and number of marginal scales help identify many clades, and are suitable for robust systematic assessments among primnoids.


Asunto(s)
Antozoos/clasificación , Filogenia , Animales , Antozoos/anatomía & histología , Antozoos/genética , Teorema de Bayes , Análisis de Secuencia de ADN , Especificidad de la Especie
4.
Zootaxa ; 3691: 1-57, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26167568

RESUMEN

We describe and figure the 20 species of stylasterid hydrozoans known from South Africa. These consist of seven new species, six range extensions, and seven species previously known from South African. Most of the specimens reported resulted from expeditions of the Pieter Faure (1898-1903) and Meiring Naude (1975-1987), and are deposited primarily in the South African Museum (Cape Town). A replacement name (Errina australis) is proposed for the junior homonym Errina hicksoni Cairns, 1991. A brief history of species discovery of the South African stylasterids is presented. The new morphological term dactyloglossa is introrduced to define a baffle-like structure found in dactylopores of some species. Of the 20 South African species, 12 (60%) are not yet known outside that area. Three patterns of distribution were noted: species confined to the tropical region of South Africa, those found in both the tropical and warm temperate regions of S. Africa, and those found only in the warm temperate regions, three in the latter group sharing their distribution with cold temperate southern South America and two with warm temperate New Zealand, representing a circum-southern temperate distribution.


Asunto(s)
Hidrozoos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Femenino , Hidrozoos/anatomía & histología , Hidrozoos/crecimiento & desarrollo , Masculino , Tamaño de los Órganos , Filogenia , Sudáfrica
5.
Zootaxa ; 3691: 58-86, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26167569

RESUMEN

The twenty species of Scleractinia (all azooxanthellate) known to occur off Argentina and the Falkland Islands (the At lantic component of the cold temperate Magellan Province) are discussed, 15 of which are documented by new records Five new species are described: Caryophyllia kellerae, C. coronula, Solenosmilia australis, Flabellum cinctutum, and Ja vania cristata. Five geographic and nine bathymetric range extensions are also documented. A brief history of species dis covery in this region is given, and a key to the species is provided.


Asunto(s)
Antozoos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Antozoos/anatomía & histología , Antozoos/crecimiento & desarrollo , Argentina , Tamaño Corporal , Océanos y Mares , Tamaño de los Órganos
7.
Zookeys ; 1113: 1-110, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36762231

RESUMEN

There is a growing interest in the exploitation of deep-sea mineral deposits, particularly on the abyssal seafloor of the central Pacific Clarion-Clipperton Zone (CCZ), which is rich in polymetallic nodules. In order to effectively manage potential exploitation activities, a thorough understanding of the biodiversity, community structure, species ranges, connectivity, and ecosystem functions across a range of scales is needed. The benthic megafauna plays an important role in the functioning of deep-sea ecosystems and represents an important component of the biodiversity. While megafaunal surveys using video and still images have provided insight into CCZ biodiversity, the collection of faunal samples is needed to confirm species identifications to accurately estimate species richness and species ranges, but faunal collections are very rarely carried out. Using a Remotely Operated Vehicle, 55 specimens of benthic megafauna were collected from seamounts and abyssal plains in three Areas of Particular Environmental Interest (APEI 1, APEI 4, and APEI 7) at 3100-5100 m depth in the western CCZ. Using both morphological and molecular evidence, 48 different morphotypes belonging to five phyla were found, only nine referrable to known species, and 39 species potentially new to science. This work highlights the need for detailed taxonomic studies incorporating genetic data, not only within the CCZ, but in other bathyal, abyssal, and hadal regions, as representative genetic reference libraries that could facilitate the generation of species inventories.

8.
BMC Evol Biol ; 11: 316, 2011 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-22034946

RESUMEN

BACKGROUND: Scleractinian corals are currently a focus of major interest because of their ecological importance and the uncertain fate of coral reefs in the face of increasing anthropogenic pressure. Despite this, remarkably little is known about the evolutionary origins of corals. The Scleractinia suddenly appear in the fossil record about 240 Ma, but the range of morphological variation seen in these Middle Triassic fossils is comparable to that of modern scleractinians, implying much earlier origins that have so far remained elusive. A significant weakness in reconstruction(s) of early coral evolution is that deep-sea corals have been poorly represented in molecular phylogenetic analyses. RESULTS: By adding new data from a large and representative range of deep-water species to existing molecular datasets and applying a relaxed molecular clock, we show that two exclusively deep-sea families, the Gardineriidae and Micrabaciidae, diverged prior to the Complexa/Robusta coral split around 425 Ma, thereby pushing the evolutionary origin of scleractinian corals deep into the Paleozoic. CONCLUSIONS: The early divergence and distinctive morphologies of the extant gardineriid and micrabaciid corals suggest a link with Ordovician "scleractiniamorph" fossils that were previously assumed to represent extinct anthozoan skeletonized lineages. Therefore, scleractinian corals most likely evolved from Paleozoic soft-bodied ancestors. Modern shallow-water Scleractinia, which are dependent on symbionts, appear to have had several independent origins from solitary, non-symbiotic precursors. The Scleractinia have survived periods of massive climate change in the past, suggesting that as a lineage they may be less vulnerable to future changes than often assumed.


Asunto(s)
Antozoos/anatomía & histología , Antozoos/genética , Evolución Biológica , Fósiles , Animales , Arrecifes de Coral , Filogenia
9.
Zootaxa ; 4979(1): 212214, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34187004

RESUMEN

In the 20 year history of Zootaxa, thirty-two papers have been published having Scleractinia as its primary focus. Twenty-four of the 32 scleractinian papers deal with Recent taxa, most of which belonging to shallow-water, reef corals. The 8 publications dealing with fossil Scleractinia include 3 monographic works, three papers discussing nomenclatural issues of individual taxa, and 2 papers deal with various aspects of select genera.


Asunto(s)
Antozoos/clasificación , Animales , Arrecifes de Coral , Fósiles , Publicaciones Periódicas como Asunto , Filogenia
10.
Zookeys ; 1066: 1-198, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36479134

RESUMEN

Globally, South Africa ranks in the top five countries regarding marine species richness per unit area. Given the high diversity, it is not surprising that many invertebrate taxa in the region are poorly characterised. The South African azooxanthellate Scleractinia (Anthozoa) is one such taxonomic group, and was last reviewed by Boshoff in 1980. Although more recent regional publications have reported on some species, there has not been a faunistic review that accounts for the country's species diversity since then. Moreover, numerous unidentified specimens representing more than three decades of sampling effort have accumulated. In this study the authors update the state of knowledge of South African azooxanthellate coral species. Specimens, particularly those within the extensive collections of the Iziko South African and Smithsonian museums, were morphologically examined and identified. Other data considered included historic data represented as imagery data, associated species data from recent research surveys, and the scientific literature. To date, the study has increased the total number of known species from 77 to 108 across eleven families, 28 new South African records, and three are new species with one new genus.

11.
Sci Rep ; 10(1): 15356, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32948822

RESUMEN

This paper reports a deep-water coral framework (a single colonial bush or a larger bioconstruction of coral covering the sea bottom), formed entirely by the scleractinian coral Eguchipsammia fistula (Alcock, 1902) (Dendrophylliidae), in the northern Red Sea waters of Saudi Arabia at a depth of about 640 m. The framework consists of mostly live corals with a total area of about 10 m2 and the length of the individual coral branches range from 12 to 30 cm. Although E. fistula is ubiquitous, this discovery is the second record of a framework formed by this species and the first discovery of a large living reef in the Red Sea. The results of the genetic study indicate the potential existence of a genetic variation of E. fistula in the Red Sea. This discovery implies that the Red Sea has favorable habitats for framework-forming DWC species and highlights the need for conducting more systematic surveys for understanding their distribution, abundance, and ecology.


Asunto(s)
Antozoos/clasificación , Antozoos/fisiología , Ecosistema , Agua de Mar/análisis , Animales , Océano Índico , Oceanografía , Arabia Saudita
12.
Sci Rep ; 10(1): 13894, 2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32807819

RESUMEN

The deep sea represents the largest and least explored biome on the planet. Despite the iconic status of the Galapagos Islands and being considered one of the most pristine locations on earth, the deep-sea benthic ecosystems of the archipelago are virtually unexplored in comparison to their shallow-water counterparts. In 2015, we embarked on a multi-disciplinary scientific expedition to conduct the first systematic characterization of deep-sea benthic invertebrate communities of the Galapagos, across a range of habitats. We explored seven sites to depths of over 3,300 m using a two-part Remotely Operated Vehicle (ROV) system aboard the E/V Nautilus, and collected 90 biological specimens that were preserved and sent to experts around the world for analysis. Of those, 30 taxa were determined to be undescribed and new to science, including members of five new genera (2 sponges and 3 cnidarians). We also systematically analysed image frame grabs from over 85 h of ROV footage to investigate patterns of species diversity and document the presence of a range of underwater communities between depths of 290 and 3,373 m, including cold-water coral communities, extensive glass sponge and octocoral gardens, and soft-sediment faunal communities. This characterization of Galapagos deep-sea benthic invertebrate megafauna across a range of ecosystems represents a first step to study future changes that may result from anthropogenic impacts to the planet's climate and oceans, and informed the creation of fully protected deep-water areas in the Galapagos Marine Reserve that may help preserve these unique communities in our changing planet.


Asunto(s)
Ecosistema , Invertebrados/fisiología , Islas , Océanos y Mares , Animales , Biodiversidad , Ecuador , Geografía , Especificidad de la Especie
13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 2): o380, 2009 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-21581976

RESUMEN

In the title compound, C(7)H(5)FO(2)·C(7)H(7)NO, a moderate-strength hydrogen bond is formed between the carboxyl group of one mol-ecule and the pyridine N atom of the other. The benzoic acid mol-ecule is observed to be disordered over two positions with the second orientation only 4% occupied. This disorder is also reflected in the presence of diffuse scattering in the diffraction pattern.

14.
Zookeys ; (822): 1-15, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30766419

RESUMEN

A history of the description of the 50 valid species of Narella is given, beginning with the first species described in 1860. To help differentiate the various species, a tabular and a polychotomous key are provided. The species in the keys are arranged using nine characters or character sets that are believed to be of value at the species level. New characters or new significance given to previously described characters used in our keys include: 1) the nature of the dorsolateral edge of the basal scale, being ridged or not, 2) the thickness of the body wall scales, and 3) the arrangement of the coenenchymal scales (imbricate or mosaic), their thickness (thin or massive), and their outer surface ornamentation (ridged or not). All characters used in the keys are illustrated.

15.
Zookeys ; (729): 1-46, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29416390

RESUMEN

Thirteen species of deep-water calcaxonian octocorals belonging to the families Primnoidae, Chrysogorgiidae, and Isididae collected from off the Galápagos and Cocos Islands are described and figured. Seven of these species are described as new; nine of the 13 are not known outside the Galápagos region. Of the four species occurring elsewhere, two also occur in the eastern Pacific, one off Hawaii, and one from off Antarctica. A key to the 22 Indo-Pacific species of Callogorgia is provided to help distinguish those species.

17.
Zootaxa ; 4532(1): 1-43, 2018 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-30647372

RESUMEN

This paper discusses and illustrates the 23 primnoid species collected by the R/V Okeanos Explorer in the US marine protected areas in the central and western Pacific, ranging from the Musician Seamounts in the north to American Samoa to the south, and the northern Mariana Islands to the west (CAPSTONE expeditions, 2015-2017). In situ photographs are provided for most species. Thirteen of the 23 species are described as new, as well as two new genera. One new genus, Macroprimnoa, possesses some of the largest polyps in the family. A dichotomous key is provided to facilitate comparisons among the 27 species of Calyptrophora. An update of the abyssal octocorallian species occurring deeper than 3000 m is provided, increasing that number from 39 to 49 species. The character of the articulating ridge, found on the distal edge of the basal body wall scales, is re-evaluated, resulting in four genera having this character state, and requiring the description of the new genus Pseudonarella.


Asunto(s)
Antozoos , Expediciones , Samoa Americana , Animales , Micronesia
18.
Zootaxa ; 4441(3): 529-536, 2018 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-30313999

RESUMEN

As part of an ongoing reassessment of the genus Callogorgia, we describe C. lucaya sp. nov. from the western Atlantic, with a distribution so far restricted to the Straits of Florida and northern Caribbean. The species was partially described in an unfinished manuscript of Dr. Frederick Bayer and differs from all other western Atlantic species by commonly lacking outer-lateral body wall scales, having a small number of abaxials, and having body wall sclerites that are externally almost smooth. (Species Zoobank LSID: urn:lsid:zoobank.org:act:CF8F92FC-8F8A-4A8C-AF4A-52E12B58F7B1).


Asunto(s)
Antozoos , Decápodos , Animales , Región del Caribe , Florida
19.
Eur J Med Genet ; 50(3): 216-23, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17369115

RESUMEN

X-linked mental retardation (XLMR) is a heterogeneous disorder with both syndromic and non-syndromic forms. Here we describe the clinical and molecular characterisation of a family with a syndromic form of XLMR with hypogonadism and short stature. We investigated a family in which four male members in two generations presented with hypergonadotrophic hypogonadism associated with development of small and abnormal testes. In two of the males, late-onset testicular ascent was noted. In addition, all affected males had short stature (<0.4th centile) and mild learning difficulties and three out of the four had microcephaly. Karyotypes were normal and endocrine investigations confirmed primary testicular failure. The phenotype segregated as an X-linked trait. Haplotype and genetic two-point linkage analysis with 22 microsatellites excluded the whole X chromosome except for a region on Xq25-Xq27 encompassing 13.7Mb with a maximum LOD score of 1.1 for marker DXS8038 at theta=0.05. One family previously described as having XLMR with hypogonadism and short stature maps to the same X chromosome region implicated in our family. However, the more severe mental retardation, muscle wasting and tremor described in this other family would suggest that our family is affected by a novel XLMR syndrome.


Asunto(s)
Cromosomas Humanos X/genética , Trastornos del Crecimiento/genética , Discapacidad Intelectual Ligada al Cromosoma X/genética , Microcefalia/genética , Enfermedades Testiculares/genética , Adolescente , Adulto , Niño , Mapeo Cromosómico , Facies , Femenino , Trastornos del Crecimiento/complicaciones , Haplotipos , Humanos , Hipogonadismo/complicaciones , Hipogonadismo/genética , Masculino , Discapacidad Intelectual Ligada al Cromosoma X/complicaciones , Discapacidad Intelectual Ligada al Cromosoma X/patología , Microcefalia/complicaciones , Repeticiones de Microsatélite , Linaje , Síndrome , Enfermedades Testiculares/complicaciones
20.
Zookeys ; (668): 1-10, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28824278

RESUMEN

A new genus and species of unbranched golden coral, Flagelligorgia gracilis, is described based on several specimens collected off the southeastern coast of the United States. The genus is provisionally included in the family Chrysogorgiidae, pending molecular confirmation. Flagelligorgia morphologically resembles other unbranched chrysogorgiids, such as Distichogorgia, Chalcogorgia, Helicogorgia and Radicipes, to which it is compared. The type species is illustrated and its distribution mapped.

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