首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The genus Eumicrotremus comprises 16 lumpsucker species distributed in the Arctic and northern Atlantic and Pacific Oceans. The most common species in the North Atlantic is Eumicrotremus spinosus , described in 1776, and characterized partly by numerous bony tubercles on the head and body. Another Atlantic species, Eumicrotremus eggvinii , described in 1956, remained known only from a single specimen until additional specimens were recently recovered. To reassess the status of E. eggvinii , 21 meristic and 32 morphometric characters were analysed for a total of 83 specimens of E. spinosus and E. eggvinii . Mitochondrial (COI, COII and cyt- b ) and nuclear ( Tmo-4C4 ) genes were also sequenced for both species, along with Eumicrotremus derjugini . The results indicate that although E. spinosus and E. eggvinii are clearly separated by a considerable number of morphological characters, they in fact constitute a single, sexually dimorphic species. Thirteen specimens of E. eggvinii (including the holotype) and 59 E. spinosus could be sexed; all individuals of E. eggvinii turned out to be males and all E. spinosus were females. Identical DNA sequences were found in all E. eggvinii and E. spinosus for COI, COII and Tmo-4C4 , and a single shared synonymous substitution found in cyt- b . In contrast, E. spinosus , E. eggvinii and E. derjugini differed by 5·9% for COI and COII, 1·2% for Tmo-4C4 and 8·3% for cyt- b .  相似文献   

2.
New data have been acquired on the biology, morphological features and distribution of Norwegian (Atlantic) pollock Theragra finnmarchica in the Barents Sea. Two individuals of this rare species gadoid (Gadidae) were caught in June and July 2012 in the south-eastern part of the Barents Sea, indicating a wider distribution area of this species than previously thought. It has been confirmed that a number of morphological features of Norwegian pollock is different from T. chalcogramma, and that it feeds on macroplankton (Euphausiidae, Hyperiidae).  相似文献   

3.
A new species of Odontostilbe is described from the rio Jaciparaná, rio Madeira basin, Rondônia, Brazil. Odontostilbe pacaasnovos differs from all its congeners, except O. pequira, by the colour pattern. Additionally, it differs from its congeners by the terminal mouth, number of cusps in the teeth of the premaxilla (5–7), number of branched rays in the anal fin (19–22), by the shape of dentary teeth (5–7 cusps with central cusp larger and longer than laterals cusps) and by the number of lamellae of the olfactory rosette (17–18 in male and 14 in female). Morphological and molecular comparisons corroborate the distinctiveness between O. pacaasnovos and its congeners, justifying its recognition as a new species.  相似文献   

4.
Four new species of the subgenus Stegana (sensu stricto) were found and described from China: S. (S.) antha sp. nov., S. (S.) latiorificia sp. nov., S. (S.) huangjiai sp. nov. and S. (S.) nigrifoliacea sp. nov. Three known Stegana (s. str.) species from China: S. (S.) antlia Okada, 1991, S. (S.) cheni Sidorenko, 1997 Sidorenko, V. S. (1997). New Asian species and new records of the genus Stegana Meigen (Diptera, Drosophilidae). I. Subgenera Oxyphortica Duda and Stegana s. str. Annales d la Société Entomologique de France (N. S.), 33, 6579.[Web of Science ®] [Google Scholar] and S. (S.) emeiensis Sidorenko, 1997 Sidorenko, V. S. (1997). New Asian species and new records of the genus Stegana Meigen (Diptera, Drosophilidae). I. Subgenera Oxyphortica Duda and Stegana s. str. Annales d la Société Entomologique de France (N. S.), 33, 6579.[Web of Science ®] [Google Scholar] are redescribed as supplementary information. A key to the species, based on morphological characters, is provided. The phylogenetic relationships among 14 species of the subgenus Stegana are reconstructed with the combined sequences of the mitochondrial genes, ND2 (NADH dehydrogenase subunit 2) and COI (cytochrome c oxidase, subunit I). Moreover, the intra- and interspecific pairwise K-2P (Kimura's two-parameter) distances among these species are summarized, and the availability of mitochondrial markers in the species identification of the subgenus Stegana are further discussed.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:368C55C3-B101-457C-BD61-BDD8F1B780E5  相似文献   

5.
Small and silvery cyprinid species from eastern Iran which are usually known as Crossocheilus latius are reviewed based on morphological and molecular characters of the mtDNA COI barcode region. We demonstrate that fishes which had been identified as Crossocheilus Kuhl & van Hasselt, 1823 in Iran actually belong to the genus Gonorhynchus McClelland, 1838 with two species: G. adiscus (Annandale, 1919) and G. diplochilus (Heckel, 1838), which are rediagnosed here. Both species are well distinguished by gill raker counts, number of scales between anus and anal fin, barbel size and minimum body depth. G. adiscus and G. diplochilus are also distinguished by molecular characters of the mtDNA COI barcode region. Both species are phylogenetically close to Gonorhynchus latius (Hamilton, 1822) which is restricted to India, Nepal and Bangladesh and to G. burmanicus (Hora, 1936), restricted to India and Myanmar. All of these four related taxa are phylogenetically closer to the genus Garra than the genus Crossocheilus (restricted to south-east Asia).  相似文献   

6.
The Mediterranean morid codling Lepidion lepidion is thought to be endemic, yet its taxonomic distinctiveness from the morphologically similar and more wide-ranging Atlantic Lepidion eques is unresolved, and has been controversial since the beginning of the twentieth century. Despite the abundant taxonomic literature questioning the interspecific relationship between these taxa, their current status remains unchanged. To elucidate the differentiation of the specimens identified as L. lepidion and L. eques collected across much of their geographic ranges, the sequence divergence of the cytochrome oxidase I “DNA barcode” gene of the mitochondrial genome was evaluated. A network analysis indicates that the most observed haplotypes are common to both species throughout their Mediterranean and North Atlantic distribution areas. This molecular evidence suggests the absence of biogeographical barriers and is insufficient to support the different species designations, giving L. eques the taxonomic status of junior synonym of L. lepidion.  相似文献   

7.
Gobies are difficult to identify, as they are very similar in appearance. Here, we identified (sub)adult specimens of 12 goby species from the North Sea and the Baltic Sea by carefully analysing meristic characters, coloration patterns, papillae row patterns and morphometric measurements. The results of the morphological identifications were congruent with those obtained with the analysis of COI DNA barcodes; sequences from morphological conspecific specimens were clustered together in clades with bootstrap values ≥ 99%. Mean intra‐ and interspecific distance (uncorrected p) was 0.37 and 18.97%, respectively. A gap between the maximum intraspecific distance and the distance to the nearest neighbour was apparent in every species and ranged from 2.35 to 16.11%. The Barcode Index Number (BIN) analysis performed on the Barcode of Life Data Systems (BOLD) web platform, assigned the DNA barcodes to 12 separate clusters corresponding to sequence‐ and morphology‐based identification. In 25% of the investigated species, the BIN clusters showed taxonomic discordances, as they contained sequences assigned to more than one species. This result demonstrates the importance of accurate morphological species identification at the beginning of the barcoding pipeline. © 2014 The Linnean Society of London  相似文献   

8.
9.
Echinocereus is a morphologically diverse genus that includes 64 species grouped into eight taxonomic sections based on morphological traits. In previous molecular phylogenetic analyses, the relationships amongst Echinocereus species were not entirely revealed and useful characters to recognize clades were not provided. The inclusion of several sources of evidence in a phylogenetic analysis is likely to produce more supported hypotheses. Therefore, we performed a combined phylogenetic analysis with a set of 44 morphological characters and six chloroplast DNA sequences. Topologies from parsimony and Bayesian analyses were mostly congruent. However, the relationships of E. poselgeri were not consistent between analyses. A second Bayesian analysis using a long-branch extraction test resulted in a topology with the morphological position of E. poselgeri congruent with that in parsimony analysis. Parsimony and Bayesian analyses corroborated the monophyly of Echinocereus, which included eight monophyletic groups. The combined phylogeny integrated into different clades those taxa that were not determined in previous analyses and changed the relationships of some recognized clades. The clades did not recover the recent infrageneric classification. In the present study, a new sectional classification for Echinocereus is proposed based on the eight recovered clades, which is supported by a combination of morphological and molecular characters. An identification key for sections in the genus is included.  相似文献   

10.
Previous studies have indicated the occurrence of nine species of Palaemon in Brazil. However, the extensive variability in their diagnostic characters and the geographic distribution of some species raises doubts about the validity of some taxa, potentially indicating the occurrence of species not yet reported from Brazil or even not described. To solve taxonomic issues with Palaemon species in Brazil, we carried out a multigene analysis by using partial fragments of 16S and COI mitochondrial genes and the nuclear H3. Phylogenetic relationships were inferred by maximum likelihood and Bayesian inference. The external morphology corresponding to the terminal clades obtained in the molecular phylogram was analysed to identify diagnostic characters that allow the recognition of the groups and the correct taxa assignment. The combined analysis of molecular and morphological data confirms the existence of nine species of Palaemon in Brazil, five from the “Palaemon” lineage (P. mercedae and four Palaemon stensu strictoP. argentinus, P. octaviae—first record in Brazil, P. northropi and P. paivai) and four of the “Alaocaris” lineage (P. carteri, P. ivonicus, P. pandaliformis and P. yuna). The possibility of further cryptic speciation is also pointed out. In addition to confirming the validity of the nine species, the results indicate the need for taxonomic adjustments and corresponding changes in the geographic distribution of Palaemon species occurring in Brazil.  相似文献   

11.
Parthenocissus (the Virginia creeper genus, Vitaceae) consists of 13 species and shows a disjunct distribution between Asia and North America. We investigated the inflorescence structure, calyx morphology, appendages on the inner side of petals, leaf epidermis, pollen and seed characters throughout the genus. A combined phylogenetic analysis with 27 morphological and 4137 molecular characters was conducted and the result was largely congruent with that of the previous molecular work, but with higher resolution. The combined analysis identified two clades corresponding to the Asian and North American taxa. Parthenocissus feddei was resolved as closely related to the clade containing P. cuspidifera, P. heterophylla and P. semicordata. The four species share synapomorphies of having conspicuously raised veinlets, an obscurely five‐ (to eight‐) lobed calyx, appendages on the inner side of petals covering the entire length of anthers and foveolate pollen exine ornamentation. Within the Old World clade, the pentafoliolate species were weakly supported as more closely related to species with both simple and trifoliolate leaves. Furthermore, the ancestral states of tendril apices, inflorescence structure, appendages on the inner side of petals and exine ornamentation of pollen grains were reconstructed on the molecular strict consensus tree. The appendages on the inner side of petals and exine ornamentation of pollen grains were suggested to be important characters in the taxonomy of Parthenocissus, especially for species with trifoliolate leaves. Finally, the previous classifications of Parthenocissus were evaluated within the phylogenetic framework. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, ?? , ??–??.  相似文献   

12.
ABSTRACT

To elucidate the taxonomy and phylogeny of Phymatolithon purpureum (P. Crouan & H. Crouan) Woelkerling & L.M. Irvine, we observed the type specimens and fresh samples using SEM (ultra-morphology) and analysed DNA sequences. Phymatolithon purpureum was originally described as Lithothamnion purpureum P. Crouan & H. Crouan from Mingant, Brittany, France. Our molecular phylogenetic analyses using psbA and COI–5P regions placed our collections from Ireland, UK and France in a clade with ‘P. borealis W.H. Adey, J.J. Hernandez-Kantun & P.W. Gabrielson (MH252286)’ from Iceland and ‘uncultured Corallinales (GQ917711 and GQ917512)’ from Roscoff, Brittany, France, near the type locality of P. purpureum. We show that P. purpureum is conspecific with P. borealis and P. polymorphum f. papillatum (Foslie) Foslie based on morphology and molecular data. Also, although P. purpureum has been often confused with P. laevigatum (Foslie) Foslie because of their similar morphology (e.g. smooth surface and sunken tetra/bisporangial conceptacles), our molecular phylogenetic analyses indicate that P. purpureum and P. laevigatum are sister taxa. Our sequences from lectotype material of P. laevigatum and syntype material of Lithothamnion emboloides Heydrich are identical.  相似文献   

13.
The willistoni species subgroup has been the subject of several studies since the latter half of the past century and is considered a Neotropical model for evolutionary studies, given the many levels of reproductive isolation and different evolutionary stages occurring within them. Here we present for the first time a phylogenetic reconstruction combining morphological characters and molecular data obtained from 8 gene fragments (COI, COII, Cytb, Adh, Ddc, Hb, kl-3 and per). Some relationships were incongruent when comparing morphological and molecular data. Also, morphological data presented some unresolved polytomies, which could reflect the very recent divergence of the subgroup. The total evidence phylogenetic reconstruction presented well-supported relationships and summarized the results of all analyses. The diversification of the willistoni subgroup began about 7.3 Ma with the split of D. insularis while D.paulistorum complex has a much more recent diversification history, which began about 2.1 Ma and apparently has not completed the speciation process, since the average time to sister species separation is one million years, and some entities of the D. paulistorum complex diverge between 0.3 and 1 Ma. Based on the obtained data, we propose the categorization of the former “semispecies” of D. paulistorum as a subspecies and describe the subspecies D. paulistorum amazonian, D. paulistorum andeanbrazilian, D. paulistorum centroamerican, D. paulistorum interior, D. paulistorum orinocan and D. paulistorum transitional.  相似文献   

14.
15.
16.
Abstract The growth of young plants of the epigeal species Phaseolus vulgaris and Glycine max is compared with that of the hypogeal species Pisum sativum and Vicia faba, with particular reference to synchronization between the exhuastion of seed reserves of N and the availability of fixed N. It is argued that the N stress symptoms which occur when these two processes are not synchronized are more common and obvious in Phaseolus or Glycine than in Pisum or Vicia. This is primarily because in these species (a) the first fixed N is used for nodule growth rather than being exported to the shoot system and (b) the first foliage leaves have a much greater area and contain a larger proportion of N reserves from the seed. It is further suggested that Phaseolus and Glycine may show the greater response to nitrogen fertilizer applied at sowing since (a) most of the applied nitrate is passed directly to the shoots (rather than being reduced in the roots as in Pisum or Vicia) and (b) in addition to being used for growth (following reduction), it may also be used prior to reduction as part of the osmotic force driving cell expansion.  相似文献   

17.
The Oriental neotenic net-winged beetles attracted attention of biologists due to conspicuous large-bodied females; nevertheless phylogenetic relationships remain contentious and only a few species are known in both the fully metamorphosed males and neotenic females. The phylogenetic analyses and morphology of larvae and adults provide data for investigation of relationships and species delineation. Platrilus Kazantsev, 2009, Platerodriloplesius Wittmer, 1944, and Falsocalochromus Pic, 1942 are synonymized to Platerodrilus Pic, 1921. Platrilus hirtus (Wittmer, 1938) and Pl. crassicornis (Pic, 1923) are transferred to Platerodrilus Pic, 1921. Platerodrilus hoiseni Wong, 1996 is proposed as a junior subjective synonym of Falsocalochromus ruficollis Pic, 1942. Platerodrilus is divided in three species-groups: P. paradoxus, P. major, and P. sinuatus groups defined based on the shape of genitalia and molecular phylogeny. The following species are described: Platerodrilus foliaceussp. n., P. wongisp. n. (P. paradoxus group); P. ngisp. n., P. wittmeri (P. major group), P. ijenensissp. n., P. luteussp. n., P. maninjauensissp. n., P. montanussp. n., P. palawanensissp. n., P. ranauensissp. n., P. sibayakensissp. n., P. sinabungensissp. n., P. talamauensissp. n., and P. tujuhensissp. n. (P. sinuatus group). P. korinchiana robinsoni Blair, 1928 is elevated to the species rank as P. robinsoni Blair, 1928, stat. n. The conspecific semaphoronts are identified using molecular phylogeny for P. foliaceussp. n., P. tujuhensissp. n., P. montanussp. n., P. maninjauensissp. n.; additional female larvae are assigned to the species-groups. Diagnostic characters are illustrated and keys are provided for P. paradoxus and P. major groups.  相似文献   

18.
This paper proposes to split the Australian Polyommatini genus Erysichton Fruhstorfer, 1916 into two genera on the basis of molecular, morphological and early stage behavioral attributes. The utility of reflective eye pattern as a taxonomic character is discussed and a neotype of Lycaena lineata Murray, 1874 is designated.  相似文献   

19.
The acetolysed pollen of 33 species of the genus Justicia in Thailand is investigated using both light and scanning electron microscopy. The pollen of the genus is characterised as being isopolar, bilaterally or radially symmetrical, with mostly prolate or prolate spheroidal shape. Based on characters with high factor loading in the cluster analysis and principal components analysis, the studied species are divided into two major groups; one with 3-colporate with six pseudocolpi and the other with 2-porate or 2–3-colporate with aperture areas. The pollen morphology of each group is described and illustrated. Pollen characters are useful for taxonomic delimitation and relationships among Thai species.  相似文献   

20.
The vegetative and reproductive morphology of the crustose red alga Peyssonnelia japonica (Segawa) Yoneshigue was re‐examined based on the holotype specimen and recent collections from various localities in Japan, including the type locality, and Hawaii. This species is characterized by the following features: thallus with appressed margins, perithallial filaments arising from the entire upper surface of each hypothallial cell (the Peyssonnelia rubra‐type), easily separable perithallial filaments in a gelatinous matrix, hypothallial filaments arranged in parallel rows, unicellular rhizoids, hypobasal calcification, gonimoblasts derived mainly from connecting filaments, and spermatangia produced in a series of whorls comprised of one to four paired spermatangia surrounding each central cell (the Peyssonnelia dubyi‐type). In addition to these features, the dimensions of the vegetative and reproductive structures of Peyssonnelia boudouresquei Yoneshigue described from Brazil were consistent with those of P. japonica. Molecular phylogenetic analyses using partial 26S rDNA, rbcL, and cox2‐3 spacer DNA sequences also supported the monophyly of P. japonica (from 16 localities in Japan and one locality in Hawaii) and P. boudouresquei (from two localities in Brazil). Therefore, P. boudouresquei may be a taxonomic synonym of P. japonica. However, considering the relatively high sequence divergences between the two taxa (2.1–2.5% in partial 26S rDNA, 5.9–6.7% in rbcL, and 5.8–6.7% in cox2‐3 spacer), and the relatively limited geographic sampling ranges, we reserve the taxonomic conclusion until further morphological and genetic data of the specimens from other geographic areas connecting Japan and Brazil become available.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号