scholarly journals Global controversy in oyster systematics and a newly described species from SE Asia (Bivalvia: Ostreidae: Crassostreinae)

2021 ◽  
Vol 51 (5) ◽  
Author(s):  
Julia D. Sigwart ◽  
Nur Leena W. S. Wong ◽  
Yuzine Esa
Keyword(s):  
New Species ◽  
Sustainable Use ◽  
Three Dimensional ◽  
Distinct Group ◽  
Distinct Species ◽  
Potential Threat ◽  
Important Species ◽  
Coi Barcoding ◽  
Morphological Diagnosis ◽  
British Colonial

AbstractThe diversity of native oysters in many regions is overshadowed by the global dominance of a few economically important species. Here we describe the Muar Oyster, Crassostrea (Magallana) saidii sp. nov., first reported as an established local fishery renowned for exceptional and distinctive flavour over 160 years ago by British colonial officials in Malaysia, but as yet never formally named or described as a species. This new species has a subtle but clear morphological diagnosis dependent on three-dimensional characters, which has long been recognised by local fishers to differentiate the new species from co-occurring C. (M.) belcheri (G. B. Sowerby II, 1871). The Indo-Pacific clade Magallana Salvi & Mariottini, 2016 in Salvi and Mariottini 2017 is a phylogenetically distinct group that nonetheless cannot be morphologically separated from the broader genus Crassostrea Sacco, 1897. Fossils or species known only from shell specimens, though morphologically distinct species, cannot be classified as Magallana, Talonostrea Li & Qi, 1994, or Crassostrea s.s.; therefore, we revise these groups as sub-genera within Crassostrea. Our analysis of the COI barcoding fragment from previously published sequences of all available Magallana species found that gene is not sufficient to separate several economically important species, and revealed more than 5% of sequences in GenBank represent identification errors. The new species Crassostrea (Magallana) saidii sp. nov., which is genetically, morphologically, and gastronomically distinct, is known from only one population under potential threat from urbanisation. Many more global species of Magallana remain undescribed. The systematics of this group is critical to understand the diversity of global oysters, and to understand the sustainable use of species grown worldwide for centuries as our food.

The Galium acutum and G. asperifolium species complexes in the eastern Himalaya

1996 ◽  
Vol 53 (2) ◽  
pp. 193-213 ◽  
Author(s):  
R. R. Mill
Keyword(s):  
New Species ◽  
South India ◽  
Distinct Species ◽  
Sensu Stricto ◽  
New Combination ◽  
Eastern Himalaya ◽  
Potential Threat ◽  
Species Complexes ◽  
Two New Species ◽  
Wall Groups

Critical discussions are presented concerning two species complexes within Galium L. (Rubiaceae). the G. acutum Edgew. and G. asperifolium Wall, groups, with special reference to the E Himalayas. In the G. acutum group, two new species, G. megacyttarion R.R. Mill sp. nov. and G. rebae R.R. Mill sp. nov., are described and G. himalavense Klotzsch & Garcke is reduced to a variety of G. acutum, necessitating a new combination. Within the G. asperifolium group, G. craticulatum R.R. Mill sp. nov. is described, and G. asperifolium and G. sikkimense Gand. regarded as distinct species. The typification of several epithets (G. blinii Lev., G. bodinieri Lév., G. cavaleriei Lév., G. comari Lév. & Vaniot, and G. esquirolii Lév.), which all antedate G. sikkimense, is discussed. Only G. cavaleriei poses a potential threat but it is here maintained separate from G. sikkimense. Brief notes on G. asperifolium sensu stricto and supposedly allied plants of south India (G. asperifolium var. pilosissimum Cufod.) are given.

A scanning electron microscopic study of the eggs of Culicoides variipennis (Diptera: Ceratopogonidae)

1987 ◽  
Vol 45 ◽  
pp. 884-885 ◽  
Author(s):  
R. A. Nunamaker ◽  
C. E. Nunamaker ◽  
B. C. Wick
Keyword(s):  
Distinct Species ◽  
Hemorrhagic Disease ◽  
Insect Vector ◽  
Electron Microscopic ◽  
Important Species ◽  
Scanning Electron Microscopic Study ◽  
Laboratory Colony ◽  
Culicoides Variipennis ◽  
Morphological Differences ◽  
Scanning Electron

Culicoides variipennis (Coquillett) is probably the most economically important species of biting midge in the U.S. due to its involvement in the transmission of bluetongue (BT) disease of sheep, cattle and ruminant wildlife, and epizootic hemorrhagic disease (EHD) of deer. Proposals have been made to recognize the eastern and western populations of this insect vector as distinct species. Others recommend use of the term “variipennis complex” until such time that the necessary biosystematic studies have been made to determine the genetic nature and/or minute morphological differences within the population structure over the entire geographic range of the species. Increasingly, students of ootaxonomy are relying on scanning electron microscopy (SEM) to assess chorionic features. This study was undertaken to provide comparative chorionic data for the C. variipennis complex.Culicoides variipennis eggs were collected from a laboratory colony maintained in Laramie, Wyoming.

scholarly journals Haemoglobin polymorphisms affect the oxygen-binding properties in Atlantic cod populations

2008 ◽  
Vol 276 (1658) ◽  
pp. 833-841 ◽  
Author(s):  
Øivind Andersen ◽  
Ola Frang Wetten ◽  
Maria Cristina De Rosa ◽  
Carl Andre ◽  
Cristiana Carelli Alinovi ◽  
...  
Keyword(s):  
Evolutionary Biology ◽  
Quaternary Structure ◽  
Atlantic Cod ◽  
Three Dimensional ◽  
Oxygen Affinity ◽  
Oxygen Binding ◽  
Low Oxygen ◽  
Binding Properties ◽  
Important Species ◽  
The North

A major challenge in evolutionary biology is to identify the genes underlying adaptation. The oxygen-transporting haemoglobins directly link external conditions with metabolic needs and therefore represent a unique system for studying environmental effects on molecular evolution. We have discovered two haemoglobin polymorphisms in Atlantic cod populations inhabiting varying temperature and oxygen regimes in the North Atlantic. Three-dimensional modelling of the tetrameric haemoglobin structure demonstrated that the two amino acid replacements Met55β 1 Val and Lys62β 1 Ala are located at crucial positions of the α 1 β 1 subunit interface and haem pocket, respectively. The replacements are proposed to affect the oxygen-binding properties by modifying the haemoglobin quaternary structure and electrostatic feature. Intriguingly, the same molecular mechanism for facilitating oxygen binding is found in avian species adapted to high altitudes, illustrating convergent evolution in water- and air-breathing vertebrates to reduction in environmental oxygen availability. Cod populations inhabiting the cold Arctic waters and the low-oxygen Baltic Sea seem well adapted to these conditions by possessing the high oxygen affinity Val55–Ala62 haplotype, while the temperature-insensitive Met55–Lys62 haplotype predominates in the southern populations. The distinct distributions of the functionally different haemoglobin variants indicate that the present biogeography of this ecologically and economically important species might be seriously affected by global warming.

Two new species in the Ficinia indica complex (Cyperaceae, tribe Cypereae) from South Africa

Phytotaxa ◽  
2017 ◽  
Vol 295 (1) ◽  
pp. 49
Author(s):  
ALUWANI A. TSHIILA ◽  
SAMSON B.M. CHIMPHANGO ◽  
JAN-ADRIAAN VILJOEN ◽  
A. MUTHAMA MUASYA
Keyword(s):  
New Species ◽  
Region Growing ◽  
Distinct Species ◽  
Cape Floristic Region ◽  
Morphological Data ◽  
Similar Species ◽  
Ecological Features ◽  
Dichotomous Key ◽  
As Species ◽  
Two New Species

Unclear boundaries between species hinder identification in the field and in herbaria, especially in species groups that can only be distinguished on the basis of subtle morphological and ecological features. One such taxon is Ficinia indica, widespread in the Greater Cape Floristic Region, growing on deep sandy soils between sea level and 1000 m elevation. Within its range, several phylogenetically related and morphologically similar species co-occur or occupy distinct habitats. Studies in herbaria show species in the Ficinia indica complex to be largely misidentified based on the use of qualitative information. Here, we investigate whether the six taxa recognized, based on one or a few characters, are supported as distinct species based on multivariate analysis of macro-morphological data. Two of the taxa were mostly separated whereas the other four taxa overlapped in multivariate space, but all the taxa could be distinguished using a single or a combination of morphological and ecological characters. We uphold the four previously recognized taxa (Ficinia argyropus, F. elatior, F. indica, F. laevis) as species, describe two new species (F. arnoldii and F. montana), and provide a dichotomous key for their identification.

scholarly journals Multigene phylogeny and morphology reveal Phaeobotryon rhois sp. nov. (Botryosphaeriales, Ascomycota)

Phytotaxa ◽  
2015 ◽  
Vol 205 (2) ◽  
pp. 90 ◽  
Author(s):  
XIN-LEI FAN ◽  
KEVIN D. HYDE ◽  
JIAN-KUI LIU ◽  
YING-MEI LIANG ◽  
CHENG-MING TIAN
Keyword(s):  
New Species ◽  
Distinct Species ◽  
Similar Species ◽  
Multigene Phylogeny ◽  
Fruiting Bodies ◽  
Canker Disease ◽  
Multigene Analysis ◽  
The Family ◽  
Rhus Typhina ◽  
A New Species

The family Botryosphaeriaceae encompasses important plant-associated pathogens, endophytes and saprobes with a wide geographical and host distribution. Two dark-spored botryosphaeriaceous taxa associated with Rhus typhina dieback and canker disease were collected from Ningxia Province, in northwestern China. Morphology and multigene analysis (ITS, LSU and EF-1α) clearly distinguished this clade as a distinct species in the genus. Phaeobotryon rhois is introduced and illustrated as a new species in this paper. The species is characterized by its globose, unilocular fruiting bodies and small, brown, 1-septate conidia. It can be distinguished from the similar species P. cercidis, P. cupressi, P. mamane and P. quercicola based on host association and conidial size and colour.

Study of the floristic diversity of Acacia tortilis population- in Bechar region (Southwestern Algeria)

2019 ◽  
Vol 9 (4) ◽  
pp. 133-141
Author(s):  
Guenaia Abdelkader ◽  
Hasnaoui Okkacha ◽  
Bekkouche Assia
Keyword(s):  
Sustainable Use ◽  
Diversity Indices ◽  
Floristic Diversity ◽  
Acacia Tortilis ◽  
Important Species ◽  
Disturbance Index ◽  
Moricandia Arvensis ◽  
Biological Spectrum ◽  
Flora Diversity ◽  
Risk Loss

For the management and sustainable use of natural bio-resources it is necessary to quantify and valorize this heritage. In the case of the floristic diversity of Acacia tortilis, the only natural woody stand in Bechar-Algeria, scanty studies have been undertaken. Hence in this study, the general overview of the flora diversity state in the 58 plots of 9 stations was made by the analysis of various indexes: Shannon, Simpson, species evenness, floristic richness, disturbance index, biological and biogeographically spectra. We listed 103 species belonging to 37 families and 85 genus, the important plants belonged to the Asteraceae and Brassicaceae. The most important species are: Pulicaria crispa, Asteriscus graveolens, Launea arborescens, Matricaria pubescens, Moricandia arvensis, Farsetia aegyptiaca, Zilla macroptera. The biological spectrum indicated a dominance of the Chamaephytes and the predominance of the Therophytes; the phytogeographic spectrum showed an important endemism (44%) in which 36% species belong to the SaharoArabian element; The Shannon, Simpson, and Evenness diversity indices, were relatively high, thereby indicating a diversity variation between the stations, witch increased South towards North. It was prominent in Zouzfana, Taghit, and Abadla stations, and the higher values of disturbance Index reflected the greater level of anthropization in these courses. The future accumulation of this regression, many risk loss of the last naturally wall of desertification, biodiversity, national economy and sand advancement. Therefore, it is recommended to apply pastures protection, pastoral charge control, and elaborate an environmental value of this species. 

The genus Arctomelon Dall, 1915 in Alaskan waters, with the description of a new species

The Festivus ◽  
2018 ◽  
Vol 50 (4) ◽  
pp. 246-263
Author(s):  
Roger Clark
Keyword(s):  
New Species ◽  
Distinct Species ◽  
Aleutian Islands ◽  
A New Species

The Volutid genus Arctomelon Dall, 1915 in Alaskan waters is examined, four species are recognized. A new species, Arctomelon borealis sp. nov. is described from bathyal depths of the central Aleutian Islands. A. stearnsii ryosukei (Habe & Ito, 1965) is recognized as a distinct species.

A reassessment of Dioon merolae (Zamiaceae) leads to the description of Dioon salas-moralesae, a new cycad species from Southeastern Oaxaca, Mexico

Phytotaxa ◽  
2021 ◽  
Vol 528 (2) ◽  
pp. 93-110
Author(s):  
JOSÉ SAID GUTIÉRREZ-ORTEGA ◽  
MIGUEL ANGEL PÉREZ-FARRERA ◽  
JEFFREY CHEMNICK ◽  
TIMOTHY J. GREGORY
Keyword(s):  
New Species ◽  
Morphological Variation ◽  
Related Species ◽  
Statistical Tests ◽  
Distinct Species ◽  
Closely Related Species ◽  
Morphometric Variation ◽  
Isthmus Of Tehuantepec ◽  
Morphological Differences ◽  
Recent Evaluation

The cycad genus Dioon comprises 17 species from Mexico and Honduras, all of them delimited based on their morphological variation and geographic distribution. A recent evaluation of the biological variation among Dioon populations from Oaxaca and Chiapas, Mexico, demonstrated that the concept of the species Dioon merolae actually consists of three lineages that should be recognized as different taxa. One lineage was already described as Dioon oaxacensis, leaving the concept of Dioon merolae comprising two lineages distributed on both sides of the Isthmus of Tehuantepec. However, there are conspicuous morphological differences between these two lineages. Here, we tested whether such a differentiation within the concept of Dioon merolae merits the differentiation of two different taxa. We evaluated the qualitative and morphometric variation among populations belonging to the Dioon merolae lineages, and compared it with the closely related species Dioon oaxacensis. Morphological observations and statistical tests demonstrated that the populations of southeastern Oaxaca, traditionally considered as part of Dioon merolae, represent a distinct species that we described as Dioon salas-moralesae. Identifying the diagnostic characters of this new species helps enable an understanding of the criteria that should be considered to delineate the boundaries between other cycad species.

Taxonomic description and 3D modelling of a new species of myzostomid (Annelida, Myzostomida) associated with black corals from Madagascar

Zootaxa ◽  
2017 ◽  
Vol 4244 (2) ◽  
pp. 277 ◽  
Author(s):  
LUCAS TERRANA ◽  
IGOR EECKHAUT
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Three Dimensional ◽  
Close Relation ◽  
Ventral Side ◽  
Middle Part ◽  
The Body ◽  
Taxonomic Description ◽  
Black Corals ◽  
Organ Systems

Eenymeenymyzostoma nigrocorallium n. sp. is the first species of myzostomid worm associated with black corals to be described. Endoparasitic specimens of E. nigrocorallium were found associated with three species of antipatharians on the Great Reef of Toliara. Individuals inhabit the gastrovascular ducts of their hosts and evidence of infestation is, most of the time, not visible externally. Phylogenetic analyses based on 18S rDNA, 16S rDNA and COI data indicate a close relation to Eenymeenymyzostoma cirripedium, the only other species of the genus. The morphology of E. nigrocorallium is very unusual compared to that of the more conventional E. cirripedium. The new species has five pairs of extremely reduced parapodia located on the body margin and no introvert, cirri or lateral organs. Individuals are hermaphroditic, with the male and female gonads both being located dorsally in the trunk. It also has a highly developed parenchymo-muscular layer on the ventral side, and the digestive system lies in the middle part of the trunk. A three-dimensional digital model of this worm’s body plan has been constructed whereby the external morphology and in toto views of the observed organ systems (nervous, digestive and reproductive) can be viewed on-screen: http://doi.org/10.13140/RG.2.2.17911.21923. 

A new Species of Cicadulina, China (Homoptera, Jassidae) injurious to Maize in Tanganyika Territory

1936 ◽  
Vol 27 (2) ◽  
pp. 251-252 ◽  
Author(s):  
W. E. China
Keyword(s):  
New Species ◽  
Distinct Species ◽  
The Gambia ◽  
The Other ◽  
Colour Pattern ◽  
Streak Virus ◽  
Research Station ◽  
Two New Species ◽  
A New Species

The genus Cicadulina was established in 1926 (Bull. Ent. Res. 17, p. 43) to hold a new species, C. zeae, China, injurious to maize in Kenya Colony. Later (Bull. Ent. Res., 19, 1928, p. 66) it was shown that Balclutha mbila, Naude, recorded as transmitting the virus of streak disease of maize in Natal, also belonged to this genus, and two new species C. arachidis and C. similis were described from the Gambia, where they were reported as injurious to ground-nut and suspected of transmitting the virus of the rosette disease of that plant. Since that time Dr. H. H. Storey of the Amani Research Station has been investigating the possibility of transmission of the streak virus of maize by C. zeae. In attempting to breed strains capable of transmission of the disease certain crosses were made which showed conclusively that he was dealing with two distinct species. These species he was able to separate on the colour pattern of the abdomen. Dr. Storey has now sent to me material of both these species and a study of the genitalia corroborates his finding. One, of course, proved to be C. zeae, the other is new and I therefore propose to dedicate it to the discoverer.

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