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1.
Ipomoea microdactyla Griseb. (Convolvulaceae) is restricted to the Bahamian archipelago, Cuba, and southeastern Florida. The species is listed as a state endangered species in Florida, where it is mostly restricted to the hyperfragmented pine rockland of Miami‐Dade County. Using seven DNA microsatellite loci, we assessed levels of genetic diversity for 12 populations of this species from Andros Island in the Bahamas (six sites), Cuba (one site), and Florida (five sites). We found significantly greater mean numbers of alleles, and higher mean values for both observed and expected heterozygosity in populations from the continuous forest on Andros than those from the habitat fragments in Florida. It is unknown if these patterns of genetic diversity in the Florida populations are the result of habitat fragmentation or founder effects. The population from Cuba exhibited relatively high levels of genetic variation, suggesting that this island is a major center of diversity and dispersal for this species. It appears that hybrid introgression for I. carolina alleles within I. microdactyla individuals occurred at a single site on Andros Island. Overall, the mean inbreeding coefficient value was 0.089, suggesting low levels of inbreeding. The highest inbreeding coefficient values were mostly recorded in Florida. Two groups were revealed, one containing the populations from Florida, and the second one encompassing those from the Bahamas and Cuba. Our results highlight the negative genetic consequences of habitat fragmentation and support initiatives recently established to establish corridors to connect the remnants of the pine forest of the Miami‐Dade County.  相似文献   

2.
Guidelines designed to aid in the restoration of rare species have been previously proposed using two primary strategies to select individuals for augmentation and reintroduction: mixing progeny from different populations or separating individuals from different populations. Understanding the genetic structure and diversity of an endangered species can offer insights into conservation management strategies. We used random amplified polymorphic DNA markers to assess the genetic structure and diversity of Jacquemontia reclinata , a federally endangered species endemic to Southeastern Florida. We sampled 20 percent of total number of individuals from eight of the ten known wild populations. Across individuals high levels of polymorphic loci (94.7%) were found and larger populations had greater genetic diversity. Cluster and ordination analyses found that one population was genetically differentiated from all the others; this population grows in a unique habitat. Most genetic variation (77.5%) was found within populations, and genetic distances between populations were not explained by their geographic distances. We recommend the use of two management units in restoration programs for J. reclinata , one consisting of the genetically differentiated population and the second consisting of the other seven populations sampled.  相似文献   

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New genetic information on the taxonomic status of an endangered species may have strong implications for its continued protection and that of other listed taxa with questionable species status. While analyzing a more comprehensive project on the molecular phylogeny of North American Spiranthes (Orchidaceae), lack of genetic differentiation between endangered S. parksii, endemic only to Texas, and a common local congener, S. cernua, was discovered. To confirm these results in a comparative context, we focused parsimony analyses on a subset of data from local Spiranthes and the same congeners found elsewhere, expanded by additional local samples of the two focal species. Four DNA sequence segments (two chloroplast, one mitochondrial, one nuclear ribosomal) totaling 3191 base pairs were used separately and together to verify that S. parksii is nested within the same clade as S. cernua, and thus likely to be the same species. Our results concur with another recent investigation using AFLP and microsatellite data that also suggests S. parksii is not unique genetically. Therefore, based on empirical data and the phylogenetic species concept, endangered S. parksii is merely an aberrant local phenotype of and a synonym for S. cernua sensu lato. Our results should be considered during the current review of this orchid’s listing status, despite some recent policy changes on consideration of genetic data after listing.  相似文献   

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Trigonostigma somphongsi, a critically endangered species, is a rare and endemic fish in Thailand. This species had disappeared from its natural habitat for 20 years until 2006. The DNA barcodes or the fragments of cytochrome c oxidase I (COI) of T. somphongsi were investigated for species identification. The remaining two native species in the genus Trigonostigma, T. heteromorpha and T. espei were also identified using Boraras urophthalmoides as an outgroup species. The 707-bp fragments were successfully amplified and sequenced in all fifteen fish samples. In the genus Trigonostigma, the genetic distance within and between species ranged from 0.000 to 0.005 and 0.016 to 0.039, respectively. The lowest genetic distance (0.016) was between T. heteromorpha and T. espei, while the highest genetic distance (0.039) was between T. somphongsi and T. espei, followed by T. somphongsi and T. heteromorpha (0.035). The phylogenetic analysis showed that the relationship between the three Trigonostigma species (T. somphongsi was clearly separated from T. heteromorpha and T. espei) agreed with the morphological characteristics. These results suggest that DNA barcoding is an effective approach to identify Trigonostigma species for use in the conservation and management of fisheries.  相似文献   

7.
Moenkhausia is one of the most speciose genera in Characidae, currently composed of 75 nominal species of small fishes distributed across South American hydrographic basins, primarily the Amazon and Guyanas. Despite the large number of described species, studies involving a substantial number of its species designed to better understand their relationships and putative monophyly are still lacking. In this study, we analysed a large number of species of Moenkhausia to test the monophyly of the genus based on the phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes. The in‐group included 29 species of Moenkhausia, and the out‐group was composed of representatives of Characidae and other members of Characiformes. All species of Moenkhausia belong to the same clade (Clade C); however, they appear distributed in five monophyletic groups along with other different genera, which means that Moenkhausia is polyphyletic and indicates the necessity of an extensive revision of the group.  相似文献   

8.
A synopsis of the P. amatista species-group in Colombia is provided. Five taxa are considered valid at species level, male and female phenotypes are associated, diagnosed and data on their distribution are given. The geographic variability of the species is discussed, and Penaincisalia celosia new species is described from specimens collected in an isolated branch of the central range in Colombian Andes. We present evidence to consider P. galeraensis (Salazar, Schmidt-Mumm, & Johnson) as a junior synonym of P. albalineata (Johnson). DNA barcodes provided additional information, which was in perfect agreement with the external characters in two of the five species. Interspecific distances were found to range from 0.6% to 6.6% (average 4.3), whilst their mean intraspecific variation ranges from 0.0% to 3.3% (average 0.7%).  相似文献   

9.
Abstract

We present a morphological feature-based key for the genus Otostephanos and describe two new species, O. jolantae sp. nov. and O. ukrainicus sp. nov. For O. jolantae sp. nov. we analysed the intraspecific morphological variability and provided the barcodes of mtCOX1 mitochondrial gene. Further, we developed a method to standardize measurements for the Philodina type of corona and trophi measurements of bdelloids. Otostephanos jolantae sp. nov. is a large rotifer with a smooth cuticle and bright red-orange gut; it can be distinguished from the known species by a high triangular upper lip with a tongue-like tip not divided into lobes, spade-shaped swollen rump, and 6/6 dental formula. It is found in Sphagnum collected in Poland, Ukraine and the Czech Republic. Otostephanos ukrainicus sp. nov. has a long body covered with coarse-grained cuticle on the last two neck segments, trunk and rump; it is distinguished by long narrow head and neck, saccular-like swollen trunk, spade-like rump, and a tiny foot. Unlike the other species of this genus, it has band-like upper lip with two narrow, sharp protrusions separated by an interspace, unusually small spurs and trophi with 5/5 major teeth. Thus far, it is only found in Ukraine, in pine and oak forest litter. http://zoobank.org/urn:lsid:zoobank.org:pub:9FC484E3-67F5-43A9-8478-A7BE14FBE5E33  相似文献   

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An extended molecular phylogenetic analysis of Uvaria (Annonaceae) is presented, using maximum parsimony, maximum likelihood and Bayesian methods, based on sequences of four plastid DNA regions (matK, psbA‐trnH spacer, rbcL and trnL‐F). The additional taxa include the monotypic West African genus Balonga, the monotypic South‐East Asian genus Dasoclema and seven Australian representatives of the genus Melodorum. The results indicate that all of these taxa are nested within a well‐supported clade otherwise consisting of Uvaria species, indicating that their taxonomic treatment needs to be reassessed. The distinguishing morphological characteristics of the taxa are re‐evaluated and interpreted as specialized adaptations of the basic Uvaria structure. The genus Uvaria is accordingly extended following the transfer of these species, necessitating six new nomenclatural combinations and two replacement names. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 33–43.  相似文献   

12.
The phylogenetic relationships of Hunter's antelope or hirola Beatragus hunteri (Artiodactyla: Alcelaphini), one of the most seriously threatened antelopes in Africa, have been the subject of controversial discussion. A total of 801 base pairs of the mitochondrial cytochrome b gene were determined from five alcelaphine species and from two nonalcelaphine bovids. Phylogenetic analysis using parsimony, maximum likelihood, and distance methods identified a single best-supported hypothesis of evolutionary relationships within the Alcelaphini: (i) monophyly of the tribe, (ii) most basal position of the blue wildebeest, (iii) sister-grouping of the Lichtenstein's and Coke's hartebeests, (iv) phylogenetic distinctiveness of the hirola from the topi and the hartebeests. We deduce that the alcelaphine cytochrome b sequences began to diverge from a common mitochondrial ancestor about 5.5 million years ago. In addition, we provide molecular evidence that the impala Aepyceros melampus is not closely related to Alcelaphini.  相似文献   

13.
A new species of Helichrysum Gaertn., H. orbicularifolium Sümbül, R. S. Göktürk & O. D. Düşen sp. nov. , is described and illustrated. The species is restricted to the south Anatolia Province, Antalya, Turkey, growing in humid calcareous rock crevices and on limestone cliffs. The species is compared with the closely related H. chasmolycicum . © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 251–254.  相似文献   

14.
Stenotaenia is one of the largest and most widespread genera of geophilid centipedes in the Western Palearctic, with a very uniform morphology and about fifteen species provisionally recognized. For a better understanding of Stenotaenia species-level taxonomy, we have explored the possibility of using molecular data. As a preliminary assay, we sampled twelve populations, mainly from the Italian region, and analyzed partial sequences of the two genes COI and 28S. We employed a DNA-barcoding approach, complemented by a phylogenetic analysis coupled with divergence time estimation. Assuming a barcoding gap of 10–16% K2P pairwise distances, we found evidence for the presence of at least six Stenotaenia species in the Italian region, which started diverging about 50 million years ago, only partially matching with previously recognized species. We found that small-sized oligopodous species belong to a single clade that originated about 33 million years ago, and obtained some preliminary evidence of the related genus Tuoba being nested within Stenotaenia.  相似文献   

15.
The Microgastrinae are a hugely diverse subfamily of endoparasitoid wasps of lepidopteran caterpillars. They are important in agriculture as biological control agents and play a significant ecological role in the regulation of caterpillar populations. Whilst the group has been the focus of intensive rearing and DNA barcoding studies in the Northern Hemisphere, the Australian fauna has received little attention. In total, 99 species have been described from or have been introduced into Australia, but the real species diversity for the region is clearly much larger than this. In this study, museum ethanol samples and recent field collections were mined for hundreds of specimens of microgastrine wasps, which were then barcoded for the COI region, ITS2 ribosomal spacer and the wingless nuclear genes, using a pooled sequencing approach on an Illumina Miseq system. Full COI sequences were obtained for 525 individuals which, when combined with 162 publicly available sequences, represented 417 haplotypes, and a total of 236 species were delimited using a consensus approach. By more than doubling the number of known microgastrine wasp species in Australia, our study highlights the value of DNA barcoding in the context of employing high‐throughput sequencing methods of bulk ethanol museum collections for biodiversity assessment.  相似文献   

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The genus Stephanus Jurine (in Panzer) is newly recorded from Japan and is represented by a new species. S. anijimensis sp. nov. from Anijima Island of the Ogasawara Islands. This species resembles S. tridentatus van Achterberg & Yang from the Oriental part of China, but can be distinguished by the combination of following characters: pronotum with a cavity under pronotal fold (cavity absent in S. tridentatus); hind femur comparatively slender, 4.8–5.1 times as long as maximum width (about 4.1 times in S. tridentatus); apical 0.5 of hind femur black or blackish‐brown (more or less yellowish in S. tridentatus). This new species was not found from other islands of the Ogasawara Islands, in which fauna is being severely endangered mainly due to predation by the introduced green anoles. Recently, it was introduced into Anijima Island in March 2013 and thus the extinction risk of this species is very high on this island.  相似文献   

18.
Melanthiaceae (Liliales) comprise 17 genera of rhizomatous or bulbous perennials and are distributed across the Northern Hemisphere. The relationships among the five tribes in this family have been evaluated in many molecular and morphological studies. In this study, we performed a phylogenetic analysis of the 17 genera, including 106 species of Melanthiaceae sensu APG III and nine related species as outgroups, based on sequences of five plastid regions (atpB, rbcL, matK, ndhF and trnL‐F). Support values for the monophyly of the family (BSMP = 96%, BSML = 100%, PPBI = 1.00) and each tribe were improved in comparison with previous studies. Among the tribes, Melanthieae were sister to the remainder of the family and sister relationships between Xerophylleae and Parideae (BSMP = 96%, BSML = 100%, PPBI = 1.00) and Chionographideae and Heloniadeae (BSMP = 96%, BSML = 100%, PPBI = 1.00) were confirmed. Notably, the generic concept of Veratrum s.l. including Melanthium was not supported in the present study and these genera should be treated as distinct. In the case of Parideae, the relationship of Trillium govanianum to the other species remains uncertain and requires further studies. Finally, we mapped seven representative morphological characters onto the molecular phylogenetic tree for Melanthiaceae.  相似文献   

19.
A new species of Megaleporinus is described from the Rio de Contas, a coastal drainage of eastern Brazil, and its phylogenetic relationships are studied using molecular data. The new species is unique among Anostomidae by possessing two exclusive features: an irregular dark longitudinal stripe from supracleithrum to second midlateral blotch and anterior cranial fontanel partially closed. In addition, the new species is diagnosed by having three premaxillary teeth, three dentary teeth, 37 or 38 scales in lateral line, 16 scale rows around caudal peduncle, three dark midlateral blotches on body, and red fins in life. The new species is closely related to M. obtusidens from the São Francisco basin, corroborating previous studies that indicated that the latter represents a species complex as currently defined. The new species exhibits the first rib enlarged in mature males, a feature described for some congeners. The new species is herein considered to be Endangered under the IUCN criteria.  相似文献   

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