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1.
A new species of Carex sect. Rhomboidales, C. jianfengensis, is described and illustrated from Hainan, China. The new species is similar to C. zunyiensis but differs in having involucral bracts sparsely hispid and with ca.1 cm long sheaths; inflorescence with 4 spikes, terminal spike ca. 2.5 cm long, lateral spikes 2–3.5 × 0.7–1 cm; staminate glumes narrowly ovate, ca. 5 mm; pistillate glumes triangular-lanceolate, 5–7 mm; perigynia 6–8 × 3 mm and pubescent on veins; nutlet 4–5 mm long, rhombic-ovoid, trigonous, base with shortly stipitate, apex abruptly contracted into a erect short beak, and not expanding into an annulate orifice.  相似文献   

2.
Three new species of Aporcelaimoides from natural habitats in Vietnam are studied, described and illustrated, including line drawings, LM and/or SEM pictures. Aporcelaimoides brevistylum sp. n. is characterized by its body 1.95–2.90 mm long, lip region offset by deep constriction and 17–18 µm broad, ventral side of mural odontostyle 11–14 µm long with aperture occupying 62–71% of its length, neck 663–767 µm long, pharyngeal expansion occupying 58–66% of total neck length, uterus a simple tube 85–182 µm long, pars refringens vaginae absent, V = 55–63, tail short and rounded (34–46 µm, c = 49–76, c’ = 0.6–0.8), spicules 67–86 µm long, and one ventromedian supplement out the range of spicules. Aporcelaimoides minor sp. n. is distinguished in having body 2.09–2.61 mm long, lip region offset by deep constriction and 19–20 µm broad, mural odontostyle 14–16 µm long at its ventral side with aperture occupying 73–84% of its length, neck 579–649 µm long, pharyngeal expansion occupying 57–66% of total neck length, uterus a simple tube 44–69 µm long, pars refringens vaginae well developed, V = 48–56, female tail very short, rounded conoid or truncate (14–26 µm, c = 90–146, c’ = 0.3–0.6), and male unknown. Aporcelaimoides silvaticum sp. n. is characterized by its body 2.09–2.60 mm long, lip region offset by depression and 17–18 µm broad, mural odontostyle 11–12 µm long at its ventral side with aperture occupying 60–66% of its length, neck 597–720 µm long, pharyngeal expansion occupying 58–64% of total neck length, uterus a simple tube 128–243 µm long, pars refringens vaginae well developed, V = 58–60, tail short and rounded (27–37 µm, c = 67–94, c’ = 0.6–0.7), spicules 64–75 µm long, and two or three widely spaced ventromedian supplements bearing hiatus. The genus Aporcelaimoides is restored, its diagnosis emended, and three species of Sectonema, namely Sectonema amazonicum, Sectonema haguei and Sectonema moderatum, transferred to it. An updated list of its species, a key to their identification and a tabular compendium with the most important morphometric features are also presented.  相似文献   

3.
Wenchengia alternifolia (Lamiaceae), the sole species of the genus Wenchengia is extremely rare and is currently listed as Critically Endangered (CR) on the IUCN Red List. The species had long been considered endemic to Hainan Island, China and was once believed to be extinct until a small remnant population was rediscovered at the type locality in 2010. Four more populations were later found on Hainan and in Vietnam. In order to develop genomic resources for further studies on population genetics and conservation biology of this rare species, we identified infraspecific molecular markers in the present study, using genome skimming data of five individuals collected from two populations on Hainan Island and three populations in Vietnam respectively. The length of plastome of the five individuals varied from 152,961 bp to 150,204 bp, and exhibited a typical angiosperm quadripartite structure. Six plastid hotspot regions with the Pi > 0.01 (trnH-psbA, psbA-trnK, rpl22, ndhE, ndhG-ndhI and rps15-ycf1), 1621 polymorphic gSSRs, as well as 1657 candidate SNPs in 237 variant nuclear genes were identified, thereby providing important information for further genetic studies.  相似文献   

4.
Pennisetum Rich. or following recent taxonomic insights Cenchrus L. is a genus with some 120 species worldwide, especially in warm areas. The genus includes some crops, some ornamentals but mostly species that are considered weedy. The name of one of the weedy species Pennisetum setaceum (Forssk.) Chiov. is also found on labels of ornamental grasses as P. setaceum “Rubrum.” It has been debated to belong to a species on its own Pennisetum advena Wipff & Veldkamp or Cenchrus advena (Wipff & Veldkamp) Morrone, only known from cultivation, whereas others still adhere to a broader species concept of P. setaceum. The recent inclusion of P. setaceum on the EU List of Union concern has revitalized the discussion on this issue for commercial reasons. Based on a morphological and molecular comparison (ITS, rbcL, and the trnh‐psbA intergenic spacer sequences) of the type specimen of P. advena, five of its “cultivars” in trade and collections of P. setaceum from different regions of the world we conclude that plants currently in trade in Western Europe belong to a separate species P. advena. A drooping inflorescence is consistent as is the difference in width of the leaf blade, the leaf blade being flat or involute, the central vein being swollen or not, and the length of the stipe being 0.3–1.1 mm in P. advena and 1.1–3.1 mm in P. setaceum. On the chloroplast markers rbcL and trnH‐psbA, the species consistently differ in 2 and 4 base pairs, respectively. On the nuclear ITS sequence, there is only 90% overlap between the two species. This justifies these ornamentals to be excluded from the List of Union concern of EU regulation 1143/2014.  相似文献   

5.
The wood sorrel family, Oxalidaceae, is mainly composed of annual or perennial herbs, a few shrubs, and trees distributed from temperate to tropical zones. Members of Oxalidaceae are of high medicinal, ornamental, and economic value. Despite the rich diversity and value of Oxalidaceae, few molecular markers or plastomes are available for phylogenetic analysis of the family. Here, we reported four new whole plastomes of Oxalidaceae and compared them with plastomes of three species in the family, as well as the plastome of Rourea microphylla in the closely related family Connaraceae. The eight plastomes ranged in length from 150,673 bp (Biophytum sensitivum) to 156,609 bp (R. microphylla). Genome annotations revealed a total of 129–131 genes, including 83–84 protein-coding genes, eight rRNA genes, 37 tRNA genes, and two to three pseudogenes. Comparative analyses showed that the plastomes of these species have minor variations at the gene level. The smaller plastomes of herbs B. sensitivum and three Oxalis species are associated with variations in IR region sizes, intergenic region variation, and gene or intron loss. We identified sequences with high variation that may serve as molecular markers in taxonomic studies of Oxalidaceae. The phylogenetic trees of selected superrosid representatives based on 76 protein-coding genes corroborated the Oxalidaceae position in Oxalidales and supported it as a sister to Connaraceae. Our research also supported the monophyly of the COM (Celastrales, Oxalidales, and Malpighiales) clade.  相似文献   

6.
Corallorhiza sinensis, a new species of mycoheterotrophic orchid from western Sichuan, China, is described and illustrated based on molecular and morphological evidence. It is morphologically similar to Corallorhiza trifida, but can be distinguished by bigger flowers, both sepals and petals with 3 veins, and longer lateral lobes of lip. To distinguish the new Corallorhiza species and explore its phylogenetic position within subtribe Calypsoinae, this study employed sequences of the nuclear ribosomal DNA (nrDNA) and whole plastome assembled from the genome skimming approach. The plastome is 148,124 bp in length, including a pair of inverted repeats (IRs) of 26,165 bp, a large single-copy region (LSC) of 82,207 bp, and a small single-copy region (SSC) of 13,587 bp. Further, phylogenetic analyses were performed using nrDNA sequence and 79 coding sequences (CDSs) from 26 complete plastomes of subtribe Calypsoinae. The phylogenetic tree based on nrDNA sequence suggested that Corallorhiza is a monophyletic group, and strongly support C. sinensis as sister to the rest species of Corallorhiza. The plastid tree showed that 10 Corallorhiza species grouped into two clades and C. sinensis is most closely related to the North American C. striata and C. bentleyi instead of Oreorchis foliosa and O.angustata in the same clade. The plastid tree and nrDNA tree indicate Oreorchis is a paraphyletic. Although the topological conflicts are displayed between plastome and nrDNA phylogenies of C. sinensis, it is still the most closely related to Corallorhiza. Comparative analysis showed that C. sinensis populations are characteristic of the intermediate morphological traits between Corallorhiza and Oreorchis. The finding of this new species from China shed new light on the phylogeny of Oreorchis and Corallorhiza.  相似文献   

7.
Four new species of Orchidaceae from China, Heminium lijiangense, Peristylus fasciculatus, Platanthera milinensis, and Ponerorchis gongshanensis, together with a new country record, Peristylus tenuicallus, are described and illustrated based on morphological and/or phylogenetic analyses. Heminium lijiangense is closely related to H. elisabethae but differs from it by having the dorsal sepal ovate-orbicular and lip mid-lobe distinctly shorter than lateral lobes. P. fasciculatus is close to Peristylus tradescantifolius but is distinguished from it by having several fascicled and straight, root-like tubers (vs. one or two oblongoid tubers), old stems usually persistent, middle lobe of lip narrowly ligulate-lanceolate and half as long as the lateral lobes (vs. middle lobe deltoid, about a third as long as the lateral lobes or less), a raised callus at the base of each lateral lobe (vs. callus absent), spur gradually attenuate toward the apex (vs. spur clavate). Platanthera milinensis is similar to P. stenochila by sharing small green flowers and lip without a spur, but differs in having a creeping rhizome, a corymbose inflorescence, and a broadly ovate and slightly 3-lobed lip. Ponerochis gongshanensis is similar to P. faberi in its small flowers, but differs in having a linear leaf c. 3 mm wide (vs. leaf 5–13 mm wide), in the lip having collar-like raised margins on the sides of the spur entrance, and a mid-lobe which is notched at the apex but not divided into two divergent lobules that are nearly as large as the lateral lobes, as in P. faberi. All the proposed species obtained high support in phylogenetic analysis as new species. The recently described genus Apetalanthe is reduced to synonymy of Ponerorchis and a new combination is made.  相似文献   

8.
Nitrogen (N) serves as an important mineral element affecting plant productivity and nutritional quality. However, few studies have addressed the interactive effects of elevated CO2 and precipitation change on leaf N of dominant grassland genera such as Stipa L. This has restricted our understanding of the responses of grassland to climate change. We simulated the interactive effects of elevated CO2 concentration and varied precipitation on leaf N concentration (Nmass) of four Stipa species (Stipa baicalensis, Stipa bungeana, Stipa grandis, and Stipa breviflora; the most dominant species in arid and semiarid grassland) using open-top chambers (OTCs). The relationship between the Nmass of these four Stipa species and precipitation well fits a logarithmic function. The sensitivity of these four species to precipitation change was ranked as follows: S. bungeana S. breviflora > S. baicalensis S. grandis. The Nmass of S. bungeana was the most sensitive to precipitation change, while S. grandis was the least sensitive among these Stipa species. Elevated CO2 exacerbated the effect of precipitation on Nmass. Nmass decreased under elevated CO2 due to growth dilution and a direct negative effect on N assimilation. Elevated CO2 reduced Nmass only in a certain precipitation range for S. baicalensis (163–343 mm), S. bungeana (164–355 mm), S. grandis (148–286 mm), and S. breviflora (130–316 mm); severe drought or excessive rainfall would be expected to result in a reduced impact of elevated CO2. Elevated CO2 affected the Nmass of S. grandis only in a narrow precipitation range. The effect of elevated CO2 reached a maximum when the amount of precipitation was 253, 260, 217, and 222 mm for S. baicalensis, S. bungeana, S. grandis, and S. breviflora, respectively. The Nmass of S. grandis was the least sensitive to elevated CO2. The Nmass of S. breviflora was more sensitive to elevated CO2 under a drought condition compared with the other Stipa species.  相似文献   

9.
A Gram negative, yellow pigmented, rod shaped bacterium designated as RLT was isolated from a hot water spring (90–98 °C) located at Manikaran in Northern India. The isolate grows at 60–80 °C (optimum, 70 °C) and at pH 7.0–9.0 (optimum pH 7.2). Phylogenetic analysis of 16S rRNA gene sequences and levels of DNA–DNA relatedness together indicate that the new isolate represents a novel species of the genus Thermus with closest affinity to Thermus thermophilus HB8T (99.5 %) followed by Thermus arciformis (96.4 %). A comparative analysis of partial sequences of housekeeping genes (HKG) further revealed that strain RLT is a novel species belonging to the genus Thermus. The melting G+C content of strain RLT was calculated as 68.7 mol%. The DNA–DNA relatedness value of strain RLT with its nearest neighbours (>97 %) was found to be less than 70 % indicating that strain RLT represents a novel species of the genus Thermus. MK-8 was the predominant respiratory quinone. The presence of characteristic phospholipid and glycolipid further confirmed that strain RLT belongs to the genus Thermus. The predominant fatty acids of strain RLT were iso-C17:0 (23.67 %) and iso-C15:0 (24.50 %). The results obtained after DNA–DNA hybridization, biochemical and physiological tests clearly distinguished strain RLT from its closely related species. Thus, strain RLT represents a novel species of the genus Thermus for which the name Thermus parvatiensis is proposed (=DSM 21745T= MTCC 8932T).

Electronic supplementary material

The online version of this article (doi:10.1007/s12088-015-0538-4) contains supplementary material, which is available to authorized users.  相似文献   

10.
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12.
Hamamelidaceae is an important group that represents the origin and early evolution of angiosperms. Its plants have many uses, such as timber, medical, spice, and ornamental uses. In this study, the complete chloroplast genomes of Loropetalum chinense (R. Br.) Oliver, Corylopsis glandulifera Hemsl., and Corylopsis velutina Hand.‐Mazz. were sequenced using the Illumina NovaSeq 6000 platform. The sizes of the three chloroplast genomes were 159,402 bp (C. glandulifera), 159,414 bp (C. velutina), and 159,444 bp (L. chinense), respectively. These chloroplast genomes contained typical quadripartite structures with a pair of inverted repeat (IR) regions (26,283, 26,283, and 26,257 bp), a large single‐copy (LSC) region (88,134, 88,146, and 88,160 bp), and a small single‐copy (SSC) region (18,702, 18,702, and 18,770 bp). The chloroplast genomes encoded 132–133 genes, including 85–87 protein‐coding genes, 37–38 tRNA genes, and 8 rRNA genes. The coding regions were composed of 26,797, 26,574, and 26,415 codons, respectively, most of which ended in A/U. A total of 37–43 long repeats and 175–178 simple sequence repeats (SSRs) were identified, and the SSRs contained a higher number of A + T than G + C bases. The genome comparison showed that the IR regions were more conserved than the LSC or SSC regions, while the noncoding regions contained higher variability than the gene coding regions. Phylogenetic analyses revealed that species in the same genus tended to cluster together. Chunia Hung T. Chang, Mytilaria Lecomte, and Disanthus Maxim. may have diverged early and Corylopsis Siebold & Zucc. was closely related to Loropetalum R. Br. This study provides valuable information for further species identification, evolution, and phylogenetic studies of Hamamelidaceae plants.  相似文献   

13.
Fallisia arabica n. sp. was described from peripheral blood smears of the Skink lizard, Scincus hemprichii from Jazan Province in the southwest of Saudi Arabia. Schizogony and gametogony take place within neutrophils in the peripheral blood of the host. Mature schizont is rosette shaped 17.5 ± 4.1 × 17.0 ± 3.9 μm, with a L/W ratio of 1.03(1.02–1.05) μm and produces 24(18–26) merozoites. Young gametocytes are ellipsoidal, 5.5 ± 0.8 × 3.6 ± 0.5 μm, with a L/W of 1.53(1.44–1.61) μm. Mature macrogametocytes are ellipsoidal, 9.7 ± 1.2 × 7.8 ± 1.0 μm, with a L/W of 1.24(1.21–1.34) μm and microgametocytes are ellipsoidal, 7.0 ± 1.1 × 6.8 ± 0.9 μm. with a L/W of 1.03(1.01–1.10) μm. In comparison to the described Fallisia species, this new taxon has rosette schizonts and is larger than F. dominicensis, in Hispaniola, F. bipocrati, F. poecilopi, in Panama, F. thecadactyli in Venezuela, and F. effusa, F. simplex, F. modesta, in Brazil. F. arabica has fewer merozoites than F. effusa, F. poecilopi, F. thecadactyli and F. siamense in Thailand. This new species has more merozoites than F. dominicensis and F. modesta. All of these species belong to diverse saurian families (Agamidae, Gekkonidae, Polychrotidae, Scincidae and Teiidae) parasitize only thrombocytes or lymphocytes and some species parasitize immature erythroid cells and leucocytes.  相似文献   

14.
A new species, the third one from Vietnam, of the genus Aporcelinus is described from natural areas. Aporcelinus falcicaudatus sp. n. is characterized by its 1.28 to 1.63 mm long body, lip region offset by weak constriction and 16 to 18 µm broad, odontostyle 18 to 21 µm at its ventral side, neck 354 to 406 µm long, uterus tripartite and 61 to 95 µm long, V = 50 to 55, tail strongly recurved dorsad and conical (23–31 µm, c = 43–58, c′ = 0.7–0.9) with finely rounded tip, and male absent. Scanning electron microscope (SEM) study, the first of a representative of the genus, shows a lip region pattern significantly different from that observed in the typical aporcelaimid taxa.  相似文献   

15.
Prunus pananensis Z. L. Chen, W. J. Chen & X. F. Jin, a new species of Rosaceae from central Zhejiang, China is described and illustrated. Micromorphological characters of the indumentum on young shoots, leaves, petioles and peduncles, including scanning electron microscope [SEM] images, are provided. This new species is morphologically similar to P. schneiderianae Koehne in having its young shoots, petioles and pedicels all densely villose, but differs in having bracts persistent, styles glabrous, stipules 8–9 mm long, stamens 28–30 of per flower, and drupes glabrous. The new species is also similar to P. discoidea (Yü & C. L. Li) Yü & C. L. Li ex Z. Wei & Y. B. Chang in having 2 or 3 flowers in an umbellate inflorescence, and bracts persistent and marginally glandular, but it differs in having young shoots and petioles densely covered with yellowish-brown villose trichomes; leaves rounded or slightly cordate at base, the mid-ribs and lateral veins abaxially densely covered with yellowish-brown villose trichomes; and hypanthium ca. 3 mm long, shorter than sepals. The atpB-rbcL and trnL-F intergenic chloroplast spacers are selected for identification of the new and its similar species.  相似文献   

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17.
We describe a new species of Telmatobius from the Pacific slopes of the Andes in central Peru. Specimens were collected at 3900 m elevation near Huaytará, Huancavelica, in the upper drainage of the Pisco river. The new species has a snout–vent length of 52.5 ± 1.1 mm (49.3–55.7 mm, n = 6) in adult females, and 48.5 mm in the single adult male. The new species has bright yellow and orange coloration ventrally and is readily distinguished from all other central Peruvian Andean species of Telmatobius but Telmatobius intermedius by having vomerine teeth but lacking premaxillary and maxillary teeth, and by its slender body shape and long legs. The new species differs from Telmatobius intermedius by its larger size, flatter head, and the absence of cutaneous keratinized spicules (present even in immature females of Telmatobius intermedius), and in males by the presence of minute, densely packed nuptial spines on dorsal and medial surfaces of thumbs (large, sparsely packed nuptial spines in Telmatobius intermedius). The hyper-arid coastal valleys of Peru generally support low species richness, particularly for groups such as aquatic breeding amphibians. The discovery of a new species in this environment, and along a major highway crossing the Andes, shows that much remains to be done to document amphibian diversity in Peru.  相似文献   

18.
Population connectivity resulting from larval dispersal is essential for the maintenance or recovery of populations in marine ecosystems, including coral reefs. Studies of species diversity and genetic connectivity within species are essential for the conservation of corals and coral reef ecosystems. We analyzed mitochondrial DNA sequence types and microsatellite genotypes of the broadcast‐spawning coral, Galaxea fascicularis, from four regions in the subtropical Nansei Islands in the northwestern Pacific Ocean. Two types (soft and hard types) of nematocyst morphology are known in G. fascicularis and are significantly correlated with the length of a mitochondrial DNA noncoding sequence (soft type: mt‐L; hard type: mt‐S type). Using microsatellites, significant genetic differentiation was detected between the mitochondrial DNA sequence types in all regions. We also found a third genetic cluster (mt‐L+), and this unexpected type may be a cryptic species of Galaxea. High clonal diversity was detected in both mt‐L and mt‐S types. Significant genetic differentiation, which was found among regions within a given type (F ST = 0.009–0.024, all Ps ≤ 0.005 in mt‐L; 0.009–0.032, all Ps ≤ 0.01 in mt‐S), may result from the shorter larval development than in other broadcast‐spawning corals, such as the genus Acropora. Nevertheless, intraspecific genetic diversity and connectivity have been maintained, and with both sexual and asexual reproduction, this species appears to have a potential for the recovery of populations after disturbance.  相似文献   

19.
Two new species of Yushania (Poaceae, Bambusoideae, Arundinarieae) are described and illustrated from Hunan, China. Yushania longshanensis D.Z. Li & X.Y. Ye is distinguished from related species (Y. confusa, Y. angustifolia and Y. pachyclada) by having a thinner culm (0.2–0.3 cm in diameter), glabrous sheath scar, no oral setae, a large glabrous leaf blade (10–20 × 0.9–1.3 cm) and 3–4 pairs of secondary veins. Yushania stoloniforma D.Z. Li & X.Y. Ye has a distinctive scrambling habit, which differs from its putative close allies. Both of these two new species have a solitary branch at the basal nodes and can be assigned to Yushania sect. Yushania based on morphological features. Additionally, we treated Yushania gigantea T.P. Yi & L. Yang as a new synonym of Y. elevata T.P. Yi and renamed Y. microphylla T.P. Yi & L. Yang as Y. weiningensis D.Z. Li & X.Y. Ye.  相似文献   

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