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Clara Lord Fabien Morat Raymonde Lecomte-Finiger Philippe Keith 《Environmental Biology of Fishes》2012,93(2):209-222
Otolith shape analysis has been used in a number of studies as an inexpensive and powerful method for categorising fish in
individual stocks. Elliptical Fourier analysis was used on three different amphidromous Sicyopterus species. Sicyopterus lagocephalus is a widespread species while the other two have a limited distribution area, Sicyopterus aiensis being endemic to Vanuatu, and Sicyopterus sarasini to New Caledonia. Both endemics live in sympatry with the widespread species. The otolith shape of all fish sampled was a
clear species differentiator, thereby demonstrating that otolith shape is species-specific. At an intraspecific level there
are different river populations within samples from Vanuatu, indicating a western group and an eastern “central” group.These
results are congruent both for the endemic species, S. aiensis and for the cosmopolitan species. Finally, we found that, for
S. lagocephalus, the cosmopolitan species, New Caledonian samples are close to western Vanuatu samples, the latter two being well differentiated
from the eastern “central” Vanuatu samples. The explanation for these results may lay either in the influence of environmental
factors on the otolith shape, or in the influence of common early life history thus reflecting genetic factors, or a combination
of both. 相似文献
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Leyla J. Seyfullah Christina Beimforde Vincent Perrichot Jouko Rikkinen Alexander R. Schmidt 《Arthropod-Plant Interactions》2017,11(4):507-514
The world’s sole ‘parasitic’ gymnosperm Parasitaxus usta (Podocarpaceae) is endemic to the island of Grande Terre, New Caledonia. It is a threatened species because of its limited geographic range and progressing habitat fragmentation. Here, we report a novel scale insect outbreak on a Parasitaxus sub-population from Monts Dzumac in the southern part of Grande Terre. The identity of the scale insect was determined through combining morphological and molecular methods. The field collection of scale insects and their secretions from infested Parasitaxus specimens allowed morphological identification of the superfamily Coccoidea. Subsequent genetic sequencing using CO1 markers allowed phylogenetic placement of the wax scale insects to the genus Ceroplastes (Coccoidea, Coccidae), a widespread pest genus. The identified species, C. pseudoceriferus, has not been previously recorded from New Caledonia. As Parasitaxus is already vulnerable to extinction, this new threat to its long-term survival needs to be monitored. Other New Caledonian endemic plant species are potentially at risk of this new species, although it was not observed on Falcatifolium taxoides, the host of Parasitaxus. 相似文献
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Summary Described and illustrated is Warneckea austro-occidentalis R. D. Stone, an endemic of tropical forests in Cameroon’s South West Province and adjacent Nigeria. The name W. mangrovensis (Jacq.-Fél.) R. D. Stone is also proposed at species level for the taxon originally described as W. fascicularis var. mangrovensis Jacq.-Fél. An IUCN (2001) status of endangered is assigned for both W. austro-occidentalis and W. mangrovensis. 相似文献
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Commiphora wightii is a medicinally important endangered species endemic to the Thar Desert of Rajasthan, India and adjoining areas of Pakistan.
The populations of this species are declining sharply because of its extensive use as a natural herb. Random amplified polymorphic
DNA analysis was conducted to find the genetic variation among 7 populations of C. wightii. Of the 100 random primers screened, 44 primers yielded 220 loci. Statistical analysis indicated low genetic diversity (H
pop = 0.0958; I = 0.1498; mean polymorphic loci = 14.28%), and high genetic differentiation among the populations (G
ST = 0.3990; AMOVA Φ
ST of 0.3390; Bayesian θ
(II) = 0.3002). The low genetic diversity may be due to geographic isolation and restricted gene flow (N
m = 0.7533) between the fragmented populations. Unsustainable utilization of the plant has fragmented the population continuum
which served the purpose of genetic exchange between populations. Mantel’s test was performed which revealed a highly significant
positive correlation between genetic and geographic distance (r
2 = 0.614, P = 0.023) among the populations studied. Low variation can also be attributed to poor seed setting and the slow growth pattern
of the species, which is also an apomict. In UPGMA dendrogram the Commiphora wightii samples were divided into two major and one minor cluster. These findings can serve as a guide to preserving the genetic
resources of this medicinal plant species. 相似文献
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Caulerpa spp. are clonal green marine algae which often act as invasive species when growing outside their native biogeographical
borders. Over the two past decades, Caulerpa taxifolia has spread along the Mediterranean coast, presently occurring at 70 sites and covering nearly 3,000 ha of subtidal area.
New genetic markers (microsatellites) have been developed to assess clonal structure and genetic diversity of recently established
populations of the invasive species C. taxifolia and Caulerpa racemosa in comparison with populations of the native Caulerpa prolifera in the Mediterranean. Our results show that nine polymorphic markers have been developed for C. prolifera, seven for C. taxifolia, and three for C. racemosa. Genetic diversity in Caulerpa was assessed in two geographical scales: one at a population scale where 40 thalli units were collected from C. prolifera in Cala d’Or, Mallorca, Spain, and another at a species scale, where 30 sample units were analyzed for C. prolifera, 24 for C. taxifolia, and 24 for C. racemosa from different sites in the Mediterranean, Atlantic, and Pacific Ocean. Number of alleles, expected heterozygosity, and marker
amplification success are provided in each case. 相似文献
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Background
Myotragus balearicus was an endemic bovid from the Balearic Islands (Western Mediterranean) that became extinct around 6,000-4,000 years ago. The Myotragus evolutionary lineage became isolated in the islands most probably at the end of the Messinian crisis, when the desiccation of the Mediterranean ended, in a geological date established at 5.35 Mya. Thus, the sequences of Myotragus could be very valuable for calibrating the mammalian mitochondrial DNA clock and, in particular, the tree of the Caprinae subfamily, to which Myotragus belongs. 相似文献11.
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A genetic transformation system has been developed for callus cells of Crataegus
aronia using Agrobacterium
tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with
5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different
types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red
colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli
were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this
is the first time to report an Agrobacterium-mediated transformation system in Crataegus
aronia. 相似文献
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Gill diplectanid monogeneans from the camouflage grouper Epinephelus polyphekadion (Bleeker) collected in the coral reef lagoon of New Caledonia, South Pacific, comprise four species. Very few monogeneans
were found in most fish examined. Pseudorhabdosynochus dionysos n. sp. has a sclerotised vagina with a robust trumpet, a robust primary canal and two chambers of similar size; it is close
to P. bacchus Sigura, Chauvet & Justine, 2007. P. viscosus n. sp. has a sclerotised vagina with a robust trumpet, long primary canal with an extremely thin wall and two small chambers,
and a male quadriloculate organ with a characteristic thickening at the extremity of its cone. P. crassus n. sp., the most abundant species, has a sclerotised vagina with a thin-walled trumpet, thin-walled primary canal which is
always coiled anteriorly and two small chambers. P. huitoe Justine, 2007, P. manifestus Justine & Sigura, 2007 and P. crassus have very similar sclerotised vaginae; however, species of this ‘huitoe complex’ can be distinguished by measurements of
the haptoral hard parts. A few diplectanid specimens found in a single specimen of E. polyphekadion were attributed to P. huitoe, a species originally described from E. maculatus (Bloch) and also rarely found in E. cyanopodus Richardson in New Caledonia; specimens from these three fish species are morphologically indistinguishable. 相似文献
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Four species of monocotylid monogeneans were found on a spotted eagle ray Aetobatus cf. narinari caught off Noumea, New Caledonia, South Pacific. The host is illustrated for future possible identification, because it belongs to a currently unresolved species complex. Decacotyle octona (Young, 1967) Chisholm & Whittington, 1998, from the secondary gill lamellae, is figured and previously unreported details of the reproductive system are described. D. elpora n. sp. is described from numerous specimens found between the secondary gill lamellae. The new species, 780-1650 microm in body length, is smaller than D. octona, but has a longer sclerotised male copulatory organ. It is characterised by two dorsal haptoral accessory structures, each with three bumps, and a 9-shaped sclerotised male copulatory organ 240-290 microm in length. D. octona and Clemacotyle australis Young, 1967, both from the branchial cavity, and Thaumatocotyle pseudodasybatis Hargis, 1955, from the nasal tissue, are new geographical records for New Caledonia. It is suggested that differences in the monocotylid fauna between the Atlantic and Indo-Pacific forms of Aetobatus cf. narinari could be of interest for the systematic status of the ray, but the sporadic nature of the sampling probably casts doubt on the usefulness of the currently available data. 相似文献
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Background
Pachycladon (Brassicaceae, tribe Camelineae) is a monophyletic genus of ten morphologically and ecogeographically differentiated, and presumably allopolyploid species occurring in the South Island of New Zealand and in Tasmania. All Pachycladon species possess ten chromosome pairs (2n = 20). The feasibility of comparative chromosome painting (CCP) in crucifer species allows the origin and genome evolution in this genus to be elucidated. We focus on the origin and genome evolution of Pachycladon as well as on its genomic relationship to other crucifer species, particularly to the allopolyploid Australian Camelineae taxa. As species radiation on islands is usually characterized by chromosomal stasis, i.e. uniformity of chromosome numbers/ploidy levels, the role of major karyotypic reshuffling during the island adaptive and species radiation in Pachycladon is investigated through whole-genome CCP analysis. 相似文献16.
Summary A new and probably endemic species of Cambessedesia DC. is described from campo rupestre vegetation, as part of a floristic survey of Melastomataceae from the S?o José mountain range, Tiradentes District, Minas Gerais State, Brazil.
Miscellaneous Accepted for publication April 2008. 相似文献
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Tyler S Zemlak Evelyn M Habit Sandra J Walde Cecilia Carrea Daniel E Ruzzante 《BMC evolutionary biology》2010,10(1):67
Background
The dynamic geological and climatic histories of temperate South America have played important roles in shaping the contemporary distributions and genetic diversity of endemic freshwater species. We use mitochondria and nuclear sequence variation to investigate the consequences of mountain barriers and Quaternary glacial cycles for patterns of genetic diversity in the diadromous fish Galaxias maculatus in Patagonia (~300 individuals from 36 locations). 相似文献18.
Helen C. F. Hopkins 《Kew Bulletin》2008,63(4):625-638
Summary
Geissois sensu stricto (i.e. excluding the Australian species of this genus) has 19 species restricted to islands in the south-west Pacific and
is the sole group in Cunoniaceae in which the stipules are intrapetiolar (axillary) in the adult foliage. In apical buds, paired opposite stipules are coherent
round their margins and are either clearly intrapetiolar in relation to the most distal pair of developed leaves (Type I,
most species), or they appear interpetiolar due to the abortion of the pair of leaves associated with them and the failure
of the internode proximal to them to elongate (Type II, a few species). Stipules are often accrescent and the largest in the
family occur in this group, reaching 10 cm long in some species. The ornithophilous racemose inflorescences of members of
this group normally consist of either axillary triads (G. hirsuta only) or apparently simple, unbranched racemes which are ramiflorous or occasionally axillary. However, bract scars on the
axes proximal to the flowers show that both types of inflorescence module usually consist of two metamers. The structure of
the inflorescences and stipules in Geissois sensu stricto supports the distinction between this group and the Australian species traditionally included in Geissois sensu lato. 相似文献
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Stefanie Kimbacher Ingrid Gerstl Branko Velimirov Sylvia Hagemann 《Molecular genetics and genomics : MGG》2009,282(2):165-172
P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding
region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Arianna Tavanti Lambert AM Hensgens Selene Mogavero László Majoros Sonia Senesi Mario Campa 《BMC microbiology》2010,10(1):203