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1.
Dehaasia pugerensis Koord. & Valeton is a threatened Indonesian Lauraceae species. It is an endemic tree known only from Jember Regency in East Java. To enhance the conservation of D. pugerensis, we conducted a population survey in several locations in Jember where the species were previously collected. The objectives were to: i) assess the current population status of D. pugerensis, ii) collect plant materials (seed, seedling, or cutting) to serve as ex situ collections, and iii) update the conservation status of the species according to IUCN Red List Category and Criteria. We only found D. pugerensis in 6 out of 16 locations in Wuluhan and Ambulu District during the survey. We successfully located 560 individuals of the species, of which 194 individuals (34.6%) were in the mature stage. Based on the diameter and height classes, the population of D. pugerensis formed a reverse J-shaped size distribution. We successfully collected 23 seeds and 15 seedlings of the species for ex situ collections. Our findings showed that the current status of D. pugerensis is Critically Endangered (CR) based on criteria B1ab(i,ii,iii,iv,v)and C2a(ii). Under these categories, the species faces an extremely high risk of extinction in the wild. Therefore, prompt comprehensive conservation actions are needed to ensure the survival of the species.  相似文献   

2.
The red alga Neorhodomela enomotoi Masuda et Kogame (Rhodomelaceae, Ceramiales) is described as a new species from Japan. It is characterized by the following combination of features: (i) thalli reddish-brown and slightly rigid; (ii) first-order branches mostly indeterminately branched; (iii) adventitious branches infrequent, determinately branched and formed chiefly in the axils of lateral branches; (iv) vegetative trichoblasts abundant; (v) tetrasporangia produced on paniculate ultimate and penultimate branches; and (vi) cystocarps flask-shaped (urceolate). This species has been found growing only in the upper subtidal zone in the warm temperate waters of Japan.  相似文献   

3.
We studied the systematics of 14 species of monogenean (Ancyrocephalidae) gill parasites from West African tilapiine hosts (Cichlidae) using both morphological and genetic data. With these tools, we were able to: (i) confirm the validity of the previously described morphological parasite species and of the genus Scutogyrus; (ii) propose that some stenoxenous species (i.e., parasite species with more than one host) may be composed of sister species (e.g., Cichlidogyrus tilapiae); (iii) state that the use of the morphology of the haptoral sclerites is more suitable to infer phylogenetic relationships than the morphology of the genitalia (which seems to be more useful to resolve species-level identifications, presumably because of its faster rate of change). These results imply that: (i) the specificity of these monogenean parasites is greater than initially supposed (what were thought to be stenoxenous species may be assemblages of oïoxenous sister species); (ii) related species groups (i.e., “tilapiae,” “halli,” and “tiberianus”) have to be, as genus Scutogyrus, validated within the 54 ancyrocephalid species described from 18 species of tilapiine hosts in West Africa, (iii) the group “tilapiae,” due to its morphology and host range, have to be considered as being the most primitive; (iv) the occurrence of lateral transfers and parallel speciation processes are necessary to describe the repartition of the newly described parasite groups on the three host genera studied (Tilapia, Oreochromis, and Sarotherodon).  相似文献   

4.
We used three different approaches, a phylogenetic analysis, the principal component analysis, and Gabriel Graphs, to study the dispersion of the medfly from its geographic centre of origin. Our analysis was based on 13 enzyme polymorphisms detected electrophoretically in 15 natural populations coming from distinct geographic areas. The results indicate that (i) there is a clear-cut separation of the native African from the introduced populations, (ii) the population from Spain seems to connect the African and the Mediterranean or American populations, and (iii) the Mediterranean populations as well as the American ones comprise two distinct groups of closely related populations.We have also estimated a phylogenetic tree for 3 species of the genus Ceratitis: C. capitata, C. rosa and C. nigra, based on electrophoretic data under the assumption of a molecular clock. The results suggest that C. capitata and C. rosa are more closely related to each other than either is to C. nigra.  相似文献   

5.
Chelimazocraes liaoi n. g., n. sp. and Chelimazocraes ascidiformis n. sp. (Monogenea: Mazocraeidae) are described from the gills of Clupanodon punctatus (Temminck & Schlegel) in Daya Bay (South China Sea). The new genus is characterised by the following features: (i) the haptor is distinctly separated from the body proper, and the arrangement of the clamps is bilaterally symmetrical but longitudinally heteromorphic; (ii) the anterior three pairs of clamps are of the mazocraeid-type, whereas the fourth pair is of a non-mazocraeid type with three sclerites; (iii) all three pairs of clamps are similar in shape but their size gradually becomes smaller from the anterior to the posterior; (iv) the inner spines of the copulatory organ have a similar shape; and (v) the testes are numerous and arranged longitudinally posterior to the ovary. The two new species are easily distinguished from other members of the Mazocraeidae by the unique structure of the fourth pair of clamps; however, there are some noticeable differences between the two species. The major differences are as follows: (i) the body of C. liaoi n. sp. is significantly larger than that of C. ascidiformis n. sp.; (ii) the anterior three pairs of clamps consist of different sclerites in the two species; and (iii) the copulatory organ has one pair of outer spines and 15–16 pieces of inner spines in C. liaoi n. sp. (vs two pairs of outer spines and 22–26 pieces of inner spines in C. ascidiformis n. sp.).  相似文献   

6.
Abstract

The Maritime Alps are one of the ‘hot spots’ in the Mediterranean basin. This study investigated two endemic plants, Moehringia lebrunii and Moehringia sedoides (Caryophyllaceae) in order to increase knowledge of the vegetation of this region, and to investigate possible conservation strategies. Ecogeographic surveys and molecular analyses were undertaken. Gene diversity, the Shannon index and GST were calculated within and among populations of the two species based on ISSR data. The populations of M. lebrunii had a density ranging between 0.04 and 0.86 individual/m2 and a rather low inner genetic variability value. According to IUCN Red List Criteria, the current status of M. lebrunii is Endangered [EN B2ab(ii, iv)]. M. sedoides is an endemic of the SW Alps (not exclusive of the Maritime Alps), and is very abundant within the core of the range. Its range of occurrence is smaller than previously reported; nevertheless, the species is not under threat. This taxon showed a population density ranging between 0.03 and 0.58 individual/m2. Genetic variability values revealed a high variation among the species. Only peripheral populations seemed to suffer from their segregated position. Thus, M. sedoides is to be considered Critically Endangered [CR B1ab(i, ii, iii, iv) + 2ab(i, ii, iii, iv)] for Italy according to Regional Guidelines.  相似文献   

7.

Background

Bacterial taxonomy and phylogeny based on rrs (16S rDNA) sequencing is being vigorously pursued. In fact, it has been stated that novel biological findings are driven by comparison and integration of massive data sets. In spite of a large reservoir of rrs sequencing data of 1,237,963 entries, this analysis invariably needs supplementation with other genes. The need is to divide the genetic variability within a taxa or genus at their rrs phylogenetic boundaries and to discover those fundamental features, which will enable the bacteria to naturally fall within them. Within the large bacterial community, Clostridium represents a large genus of around 110 species of significant biotechnological and medical importance. Certain Clostridium strains produce some of the deadliest toxins, which cause heavy economic losses. We have targeted this genus because of its high genetic diversity, which does not allow accurate typing with the available molecular methods.

Results

Seven hundred sixty five rrs sequences (> 1200 nucleotides, nts) belonging to 110 Clostridium species were analyzed. On the basis of 404 rrs sequences belonging to 15 Clostridium species, we have developed species specific: (i) phylogenetic framework, (ii) signatures (30 nts) and (iii) in silico restriction enzyme (14 Type II REs) digestion patterns. These tools allowed: (i) species level identification of 95 Clostridium sp. which are presently classified up to genus level, (ii) identification of 84 novel Clostridium spp. and (iii) potential reduction in the number of Clostridium species represented by small populations.

Conclusions

This integrated approach is quite sensitive and can be easily extended as a molecular tool for diagnostic and taxonomic identification of any microbe of importance to food industries and health services. Since rapid and correct identification allows quicker diagnosis and consequently treatment as well, it is likely to lead to reduction in economic losses and mortality rates.  相似文献   

8.
9.
A new, marine, sand‐dwelling raphidophyte from Sylt, Germany, Haramonas viridis Horiguchi et Hoppenrath sp. nov. is described. This represents a second species in the previously monotypic genus Haramonas, which was originally described from a sand sample from a mangrove river mouth in tropical Australia, based on the type species, H. dimorpha. This new species from a cold temperate region: (i) possesses a tubular invagi‐nation in the posterior part of the cell; (ii) produces copious amounts of mucilage in culture; (iii) possesses both motile and non‐motile stages in its life cycle; and (iv) has overlapping discoidal chloroplasts, all of which are diagnostic features of the genus Haramonas. Therefore, it is indisputable that this species belongs to this genus. However, the species from Sylt differs from the type species of the genus in: (i) having a larger cell size; (ii) possessing a larger number of chloroplasts; and (iii) being greenish in color. The ultrastructural study revealed that the structure of the tubular invagi‐nation was the same as that of the type species.  相似文献   

10.
《Flora》2005,200(3):245-255
This paper complements the diagnosis of the recently described genus Diamantina and its only species Diamantina lombardii Novelo, Philbrick and Irgang from Minas Gerais (Brazil). Four new features not known from other Podostemaceae–Podostemoideae are documented by microtome sections and SEM graphs: (i) The digitate foliage leaves lack vascular tissue completely. (ii) Leafy shoots produce one or two flowers in terminal and subterminal position. The spathella subtending the subterminal flower is scale-like and positionally homologous to a digitate bract (leaf), whereas the spathella covering the terminal flower bud is tubular (as usual for Podostemoideae). (iii) The usually rudimentary androecium consists of two stamens which form a complete whorl together with three inconspicuous tepals around the gynophore. (iv) The bilocular ovary has an apical cleft. Each carpel tip (hollow inside) is topped by a prominent horn-like stigma. Additional peculiar features of D. lombardii (already mentioned in Philbrick et al., 2004. Syst. Bot. 29, 109–117) are shown: presence of a prominent gynophore (mainly known from African Podostemoideae), and digitate leaves (as found in Cladopus from Eastern Asia to NE Australia).  相似文献   

11.
Cardicola Short, 1953 is a genus of the Aporocotylidae Odhner, 1912 (Digenea), with 25 currently recognised species described from 32 species of Perciformes and Mugiliformes fishes around the world, including eight species from the Great Barrier Reef. Here, we describe two new species from this region, namely Cardicola beveridgei n. sp. from the ventricle and atrium of the mangrove jack, Lutjanus argentimaculatus (Forsskål) (Perciformes: Lutjanidae), and Cardicola bullardi n. sp. from the ventricle of the Australian spotted mackerel, Scomberomorus munroi Collette & Russo (Perciformes: Scombridae), from off Lizard Island, Queensland, Australia. These two new species are most easily distinguished from the 25 current members of Cardicola in having the combination of i) a spinous oral sucker, ii) an anteriorly intercaecal ovary, iii) a uterus that extends anteriorly from the oötype, iv) the number of spines per ventrolateral transverse row, and in v) body size and the length/width ratio, vi) the oesophagus and caecal length(s) relative to body total length, vii) the length of the posterior caeca relative to the anterior pair, viii) the testis length/width ratio and its total size relative to that of the body, ix) the postovarian field as a percentage of body length, and x) egg size. In addition, C. beveridgei n. sp. is further differentiated by possessing a female genital pore that opens anterodextral to the male pore while C. bullardi n. sp. differs further in possessing a testis that is almost entirely intercaecal and does not extend anteriorly to the level of the intestinal bifurcation. Employing genetic analysis of ITS2 rDNA sequence data, representing these species and a further 13 recognised and three putative species of Cardicola, we were able to unequivocally confirm these specimens as distinct (9–22% different over 420 nucleotide positions). Distance analysis of ITS2 showed that i) species of Cardicola from the Siganidae formed a monophyletic clade, to the exclusion of other Cardicola species reported from the Scombridae, Sparidae, Lutjanidae and Chaetodontidae, ii) a general phylogenetic isolation exists between the species of Cardicola reported from scombrid fishes, and iii) C. beveridgei n. sp. and Cardicola milleri Nolan & Cribb, 2006 from lutjanids and Cardicola chaetodontis Yamaguti, 1970 from chaetodontids are phylogenetically close, despite the evolutionary remoteness between the host groups and their highly disparate biology. Given the likelihood of many additional species being attributed to Cardicola, we predict that continued molecular analyses will indicate that this genus will prove to incorporate a series of radiations in association with particular fish taxa as well as evidence of host-switching. (Nucleotide sequences reported in this paper are available in the GenBank database under accession no. KF752497).  相似文献   

12.
Tricholeiperia trinidadensis n. sp. from the small intestine of Natalus tumidirostris haymani and Natalus sp. in the Tamana caves, Trinidad, West Indies is described and illustrated. The species is separated from the other five species in the genus, namely, T. leiperi Travassos, 1935, T. proencai Travassos, 1937, T. carnegiensis Chitwood, 1938, T. pearsei Chitwood, 1938 and T. poeyi Barus & Valle, 1967. It is characterised by (i) the morphology of the cephalic vesicle which is umbrella shaped, asymmetrical and almost undivided, (ii) the shape and size of the alate, filiform spicules which have a short external alate branch near the pointed distal tip, (iii) the presence of a vulvar flap, (iv) the presence of a median notch on the posterior bursal margin, (v) the dorsal ray which divides distally each branch dividing again into three branches, and (vi) the lateral rays which have a common stem, the antero-lateral and medio-lateral, fused for most of their length, diverging distally and the shorter postero-lateral arising near the base of the other lateral rays.  相似文献   

13.
周杰  陈俊愉 《植物研究》2010,30(6):649-650
报道了中国菊属(Chrysanthemum)一新变种——阔叶毛华菊(Chrysanthemum vestitum(Hem sl.)Stapf.var.latifolium J.Zhou et J.Y.Chen)。本变种与模式变种的区别在于直立生长,并且较多分枝,叶较狭,卵状披针形或匙形,长4~6 cm,宽2~3 cm。花序直径较原种为小,约3.5~4.5 cm。主要分布于湖北宜昌、河南伏牛山山脉。抗旱性较原变种强。而主要原产于安徽西部大别山麓之模式变种则铺散生长,较少分枝,叶圆形、卵圆形,长4~7cm,宽3~5 cm。花序直径较大,约4.5~5.0 cm。  相似文献   

14.
A new red alga, Dasya enomotoi, is described from Japan. This species is characterized by having a large thallus consisting of an elongated axis and many, radially arranged, polysiphonous branches both of which are heavily corticated and densely covered with numerous, soft monosiphonous filaments. It is distinguished from several similar species by the combination of the following: (i) indistinct pericentral cells in transverse sections except near the apices, (ii) the presence of enlarged, inner cortical cells, (iii) radially arranged adventitious monosiphonous filaments, (iv) three‐celled carpogonial branches, (v) six (sometimes five) tetrasporangia in each fertile segment of the stichidia, and (vi) three tetrasporangial cover cells that are not elongated longitudinally and usually not divided transversely. This species may have been identified as D. villosa Harvey by previous investigators in Japan.  相似文献   

15.
1. Fig trees require host‐specific agaonid fig wasps for pollination, but their figs also support numerous non‐pollinating fig wasps (NPFW) that gall fig tissues or develop as parasitoids. 2. Ficus microcarpa L. is widely naturalised outside its native range and the most invasive fig tree species. Seed predators are widely used for the biological control of invasive plants, but no obligate seed predatory (as opposed to ovule or fig wall galling) NPFW have been recorded previously from any fig trees. 3. Philotrypesis NPFW are usually regarded as parasitoids or ‘inquilines’ (parasitoids that also eat plant material) of pollinator fig wasps, but the present study provides evidence that Philotrypesis taiwanensis, a NPFW associated with F. microcarpa, is an obligate seed predator: (i) adults emerge from seeds of typical appearance, with a surrounding elaiosome; (ii) it shows no preference for figs occupied by fig wasp species, other than the pollinator; (iii) it only develops in figs that contain pollinated ovules, avoiding figs occupied by an agaonid that fails to pollinate; (iv) larvae are distributed in layers where seeds are concentrated and (v) it has a negative impact on seed but not pollinator offspring numbers. 4. Philotrypesis is a large genus, and further species are likely to be seed predators.  相似文献   

16.
Platycladus Spach is native to Central China, but its natural occurrences are very difficult to establish. According to molecular phylogenetic data, this genus might have originated since the Oligocene, but no fossil record has been reported. Here, we describe eight foliage branches from the upper Miocene in western Yunnan, Southwest China as a new species, P. yunnanensis sp. nov., which is characterized by foliage branches spread in flattened sprays, and leaves decussate, imbricate, scale-like and dimorphic. The leaves are amphistomatic, and the stomata are elliptical or oblong, haplocheilic, and monocyclic type. Based on a detailed comparison with the extant genera of Cupressaceae sensu lato, our fossils are classified into the genus Platycladus. The occurrence of P. yunnanensis sp. nov. indicates that this genus had a more southernly natural distribution in the late Miocene than at present. Molecular phylogeny and fossil records support a pre-Oligocene common ancestor for the genera Platycladus, Microbiota and Calocedrus. The separation of the three taxa was most likely caused by the arid belt across Central China during the Oligocene. In addition, the cooling down of the global temperature and the strengthening of Asian monsoon since the Miocene will further promote the migration of these genera.  相似文献   

17.
Upper Paleozoic sphenopsids from western Gondwana are little known. New finds were made from the Upper Carboniferous of the San Juan province (Argentina). The specimens include vegetative and fertile characters that allow the definition of a new genus and species: Gondwanites subtilis. They are characterized by slender branches bearing whorls of very thin, simple or divided leaves. Simple fertile organs are borne in whorls just below the verticel of leaves. The presence of dichotomized leaves and bractless fertile organs in the new taxon suggests its probable primitive condition.  相似文献   

18.
19.
Two species of the crustose red algal genus Peyssonnelia (Gigartinales, Peyssonneliaceae) are reported from Japanese waters for the first time. These species share the following combination of vegetative and reproductive features: thalli with appressed margins, perithallial filaments arising from the whole upper surface of each hypothallial cell (the Peyssonnelia rubra‐type anatomy), unicellular rhizoids, hypobasal calcification and spermatangia that are produced in double chains (the Peyssonnelia harveyana‐type spermatangial filament). However, they differ obviously from each other in the hypothallus orientation as seen from below, the perithallus structure in relation to the consistency of the crust, the origin of gonimoblasts and the elevation of the nemathecia. Peyssonnelia armorica is characterized by: (i) hypothallial filaments comprising a polyflabellate layer; (ii) easily separable perithallial filaments in a gelatinous matrix; (iii) gonimoblasts originating exclusively from the auxiliary cell; and (iv) semi‐immersed (slightly elevated) nemathecia. Peyssonnelia harveyana is characterized by: (i) hypothallial filaments arranged in parallel rows; (ii) closely packed perithallial filaments in a firm matrix; (iii) gonimoblsts originating from both the auxiliary cell and the connecting filament; and (iv) conspicuously elevated nemathecia.  相似文献   

20.
Investigating crop origins is a priority to understand the evolution of plants under domestication, develop strategies for conservation and valorization of agrobiodiversity and acquire fundamental knowledge for cultivar improvement. The date palm (Phoenix dactylifera L.) belongs to the genus Phoenix, which comprises 14 species morphologically very close, sometimes hardly distinguishable. It has been cultivated for millennia in the Middle East and in North Africa and constitutes the keystone of oasis agriculture. Yet, its origins remain poorly understood as no wild populations are identified. Uncultivated populations have been described but they might represent feral, i.e. formerly cultivated, abandoned forms rather than truly wild populations. In this context, this study based on morphometrics applied to 1625 Phoenix seeds aims to (1) differentiate Phoenix species and (2) depict the domestication syndrome observed in cultivated date palm seeds using other Phoenix species as a “wild” reference. This will help discriminate truly wild from feral forms, thus providing new insights into the evolutionary history of this species. Seed size was evaluated using four parameters: length, width, thickness and dorsal view surface. Seed shape was quantified using outline analyses based on the Elliptic Fourier Transform method. The size and shape of seeds allowed an accurate differentiation of Phoenix species. The cultivated date palm shows distinctive size and shape features, compared to other Phoenix species: seeds are longer and elongated. This morphological shift may be interpreted as a domestication syndrome, resulting from the long-term history of cultivation, selection and human-mediated dispersion. Based on seed attributes, some uncultivated date palms from Oman may be identified as wild. This opens new prospects regarding the possible existence and characterization of relict wild populations and consequently for the understanding of the date palm origins. Finally, we here describe a pipeline for the identification of the domestication syndrome in seeds that could be used in other crops.  相似文献   

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