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1.
Kevin L. Keegan James Donald Lafontaine Niklas Wahlberg David L. Wagner 《Systematic Entomology》2019,44(2):451-464
Amphipyrinae have long been a catchall taxon for Noctuidae, with most members lacking discernible morphological synapomorphies that would allow their assignment to one of the many readily diagnosable noctuid subfamilies. Here data from seven gene regions (> 5500 bp) for more than 120 noctuid genera are used to infer a phylogeny for Amphipyrinae and related subfamilies. Sequence data for 57 amphipyrine genera – most represented by the type species of the genus – are examined. We present here the first large‐scale molecular phylogenetic study of Amphipyrinae and the largest molecular phylogeny of Noctuidae to date; several proposed nomenclatural changes for well‐supported results; and the identification of areas of noctuid phylogeny where greater taxon sampling and/or genomic‐scale data are needed. Adult and larval morphology, along with life‐history traits, for taxonomic groupings most relevant to the results are discussed. Amphipyrinae are significantly redefined; many former amphipyrines, excluded as a result of these analyses, are reassigned to other noctuid subfamily‐level taxa. Four genera, Chamaeclea Grote, Heminocloa Barnes & Benjamin, Hemioslaria Barnes & Benjamin and Thurberiphaga Dyar, are transferred to the tribe Chamaecleini Keegan & Wagner tribe n. in Acontiinae. Stiriina is elevated to Stiriinae rev. stat. , Grotellina is elevated to Grotellinae rev. stat. and Annaphilina is elevated to Annaphilini rev. stat. Acopa Harvey is transferred to Bryophilinae, Aleptina Dyar is transferred to Condicinae, Leucocnemis Hampson and Oxycnemis gracillinea (Grote) are transferred to Oncocnemidinae, Nacopa Barnes & Benjamin is transferred to Noctuinae and Narthecophora Smith is transferred to Stiriinae. Azenia Grote (and its subtribe Azeniina), Cropia Walker, Metaponpneumata Möschler, Sexserrata Barnes & Benjamin and Tristyla Smith are transferred to Noctuidae incertae sedis. Hemigrotella Barnes & McDunnough (formerly in subtribe Grotellina) is retained in Amphipyrinae. Argentostiria Poole and Bistica Dyar are retained in Stiriini but removed from incertae sedis position. This published work has been registered on ZooBank: http://zoobank.org/urn:lsid:zoobank.org:pub:4A140782‐31BA‐445A‐B7BA‐6EAB98ED43FA . 相似文献
2.
Computer simulations are used to predict the behavior of pollen grains with different physical properties within the acceleration field created around the ovules of the gymnosperm Ephedra trifurca. A modelling procedure is given that (1) calculates the number of pollen grains captured by an ovule's pollination-droplet and (2) gives a correlation between pollination efficiency and the physical properties (= mass, size) of different types of pollen. Based on this procedure, the number of Ephedra pollen grains captured by micropyles can be less than the number captured from other species. However, the mass and size of Ephedra pollen grains appear to coincide with those predicted to yield a local maximum of pollination efficiency, i.e. slightly larger or smaller values of either mass or size would decrease the probability of capture. In addition, the properties of Ephedra pollen grains operate synergistically in the aerodynamic environment around ovules and are focused to collide with pollination-droplets. By analogy, the properties of Ephedra pollen coincide with those predicted for a localized adaptive peak. The physical properties of pollen grain types other than E. trifurca that can maximize pollen capture are not generally represented in the aerobiology of Ephedra during the pollination season. Therefore, the phenology of pollen release, community taxonomic-composition, and the physics of particle capture play collectively important roles in the reproductive success of Ephedra trifurca. 相似文献
3.
Perianth MP, gynoecium MG, and androecium MA dry-weight biomass(in g) of 39 species of perfect flowers was measured. Thesedata were pooled with published data from an additional 51 speciesand used to determine size-dependent variations in (MG and MA)in terms of the hypothesis that the quotient of MG and MA exceeds1·0 for out-breeding (xenogamous) species and less than1·0 for in-breeding (autogamous) species. Ordinary leastsquare regression of the pooled data (n = 90) showed MG = 0·118M0·916P (r2 = 0·884) and MA = 0·186 M0·975P(r2 = 0·865), indicating that the biomass of the gynoeciumproportionally decrease as floral size increases. The exponentsof these regressions indicate that the ratio of gynoecial toandroecial biomass decreased with increasing floral size suchthat comparatively small flowers (MP < 0·0021 g) hadMG/MA > 1·0 (predicted for 'out-breeders') while comparativelylarger flowers (MP > 0·0021 g) had MG /MA < 1·0(predicted for 'in-breeders'). Thus, on average, the type ofbreeding system was a size-dependent phenomenon. To test whether the biomass of a floral organ-type is a legitimateindicator of gender reproductive effort, the biomass (in g)of stamen filaments Mm and anther sacs MAS of 39 species wasdetermined. Least square regression of these data showed MAS= 0·188 M0·854fil (r2 = 0·967), indicatingthat species with larger stamen filaments, on the average, boreproportionally smaller anther sacs and thereby cautioning againstthe uncritical use of the allocation of biomass to floral organ-typeas a strict gauge of gender-function investment. To determine whether the loss of one gender-function resultsin proportional reallocation of biomass to the remaining gender-function,the size-dependency of androecial and gynoecial biomass wasdetermined for a total of 33 perfect and imperfect flowers ofCucumis melo. Regression of the data obtained from perfect flowersyielded MA = 0·402 M1·47P (r2 = 0·898)and MG = 4·63 M1·36P (r2 = 0·842). SinceMG/MA M0·11P , the biomass allocation to the gynoeciumrelative to the androecium decreased with increasing floralsize. This result was consistent with the broad interpecificcomparison based on 90 species with perfect flowers . Regressionof the data for imperfect flowers yielded MA = 0·151M1·02P (r2 = 0·675) and MG = 4·68 M1·47P(r2 = 0·996), indicating a near allometric relation forthe androecium and a strong positive anisometry for the gynoecium.Thus, for flowers of comparable size, a loss of female genderobtains a modest to significant again in androecial biomasswhereas the loss of male gender yields only a slight increasein gynoecial biomass. Collectively, the results of these studies indicate that biomassallocation patterns are size-dependent phenomena whose complexitieshave been largely ignored in the literature.Copyright 1993,1999 Academic Press Allometry, floral biomass, reproduction 相似文献
4.
Testing 'Economy in Design' in Plants: are the Petioles and Rachises of Leaves 'Designed' According to the Principle of Uniform Strength? 总被引:2,自引:0,他引:2
Fifteen petioles and rachises from three dicotyledon species(Acer saccharum, A. negundo, and Aesculus hippocastanum), apalm (Chamaedorea erumpens), and a fern (Cyrtomium falcatum)were used to test the hypothesis of 'economy in design' in termsof the design principle of uniform strength, i.e. a beam inwhich the section modulus (Z) varies along beam-length (L) inthe same proportion as the bending moment (M). Such a beam is'economical' regarding the amount of material used in its 'construction'because each of its cross section has the minimum transversearea required to satisfy the conditions of strength. The extentto which the morphology of a petiole or rachis conformed withthis design principle was initially evaluated by normalizingZ (measured at a distance, x, from the tip of a petiole or rachis)with respect to the magnitude of Z measured at the base of thepetiole. The normalized values were plotted against normalizedpetiole-rachis length (x/L). The design principle was judgedto be demonstrated when such a plot was found to be isometric,i.e. when the plot had a slope of unity. This procedure wastested further by plotting M/Z vs. x/L for representative leavesof C. erumpens and A. saccharum, and judged adequate. The allometriesof all six simple/palmate leaves were found not agree with thedesign principle. The taperings of nine petioles and rachisesfrom pinnate leaves were consistent with the design principle.This was interpreted to provide circumstantial evidence for'economy in design' in the petioles of some pinnate leaves andevidence that the mechanical 'design' of the petioles of somesimple/palmate leaves differs substantially from that of pinnateleaves.Copyright 1993, 1999 Academic Press Leaf biomechanics, plant adaptation, petioles, rachises 相似文献
5.
Karl J. Niklas 《American journal of botany》1992,79(7):820-827
The influence of gravity on the size and mechanical properties of mature leaves on horizontal shoots and etiolated seedlings of Acer saccharum Marsh. (Aceraceae) was examined. Leaves were grouped into three categories regarding their location on shoots (dorsal or “top” T, lateral or “left/right” L/R, and ventral or “bottom” B). Young's modulus E, petiole length L, lamina surface area A and weight P, and the cross-sectional areas of different tissues within petioles were measured for each leaf and were found to be correlated with leaf location (T, L/R, and B): T leaves were smaller and had lower E than their B counterparts; the size and material properties of L/R leaves were intermediate between those of T and B leaves. In general, A, P, and E decreased from the base to the tip of shoots. In addition to anisophylly, the influence of gravity induced petiole bending and torsion and resulted in the horizontal planation of laminae. This was observed for field-grown mature plants and etiolated seedlings. Petiole bending and torsion were interpreted as gravimorphogenetic phenomena. Anatomically, L, E, and petiole deflection angle Fv measured from the vertical were highly correlated with the combined cross-sectional areas of phloem fibers and xylem in petioles of B leaves and when data from all leaves were pooled. It is tentatively advanced that the correlation of E with the transverse areas of phloem fibers and xylem is evidence that either the pattern or the extent of lignification of petiole tissues is influenced by petiole position with respect to gravity. 相似文献
6.
Niklas Bergstr?m Per-Erik Jansson Mogens Kilian Uffe B Skov S?rensen 《European journal of biochemistry》2003,270(10):2157-2162
Streptococcus mitis strain SK598, which represents a subgroup of biovar 1, possesses a unique variant of the C-polysaccharide found in the cell wall of all strains of Streptococcus pneumoniae and in some strains of S. mitis. This new variant lacks the choline methyl groups in contrast to the previously characterized forms of C-polysaccharide, which all contain one or two choline residues per repeat. The following structure of the repeating unit of the SK598 polysaccharide was established: where AAT is 2-acetamido-4-amino-2,4,6-trideoxy-d-galactose. This structure is identical to the double choline-substituted form of C-polysaccharide, except that it is substituted with ethanolamine instead of choline. This extends the number of recognized C-polysaccharide variants to four. 相似文献
7.
Chemical data are given forCooksonia, Rhynia, Zosterophyllum, Pseudosporochnus, Gosslingia,Crenaticaulis, Leclercqia, Tetraxylopteris, Oocampsa, andArchaeopteris, thus extending principal component analysis of multi-state and discrete characters to 27 Paleozoic plant taxa. Ordination patterns of these data suggest that while overlapping of major plant groups occurs, rhyniophytes, zosterophyllophytes, trimerophytes and other supra-generic taxa may be chemically characterized. The effects of heat (thermolysis) on organic constituents is shown to severely alter chemical profiles of plant taxa and is discussed as a thermometric tool. Taxonomic distancemeasures between plant groupings are suggested to be the result of both preand post-fossilization phenomena. 相似文献
8.
Karl J. Niklas 《American journal of botany》1981,68(5):635-650
Aerodynamic analyses showing characteristic airflow patterns and the potential for wind-mediated pollination are presented for models of Paleozoic (Carboniferous) ovules and ovulate cupules (i.e., Genomosperma kidstoni, G. latens, Salpingostoma dasu, Physostoma elegans, Eurystoma angulare, and Stamnostoma huttonense). Lobes on ovules and cupules are shown to produce localized regions of turbulent flow with a concomitant reduction in airflow velocity. Data based upon models that mimic the characteristics of windborne pollen (= pseudopollen) show that these regions of turbulent flow correspond to those in which suspended pseudopollen impact with ovule and/or cupule surfaces. These data have bearing on a sequence of ovule morphologies purported to show the evolution of the integument by the progressive reduction in length of “preintegumentary” lobes and their acropetal fusion. As the preintegumentary lobes of the models studied consolidate around the megasporangium, regions of turbulent flow and high pseudopollen impact become localized around the pollen chamber or salpinx. The general morphologic trend envisioned for the evolution of the ovule is seen to be associated with an aerodynamic streamlining and an increased potential for wind-mediated pollination. Data for hair-bearing ovules and for ovulate cupules are discussed within the context of possible selective pressures favouring streamlining. 相似文献
9.
E. Iwarsson Monalill Lundqvist José Inzunza Lars Ährlund-Richter Peter Sjöblom Örjan Lundkvist Niklas Simberg Magnus Nordenskjöld Elisabeth Blennow 《Human genetics》1999,104(5):376-382
We have studied the chromosomal content in 68 normally fertilised freeze-thawed human embryos of good morphology from 34
patients with an average maternal age of 32,6 years. Forty embryos showed post-thaw cellular division and twenty-eight post-thaw
cleavage arrest. After spreading of the embryos on microscope slides, analysis of chromosomes X, Y, 15, 16, 17 and 18 was
performed using two rounds of fluorescent in situ hybridisation (FISH). According to the results, the embryos were divided into four groups: (I) normal, all nuclei uniformly
diploid, (II) diploid mosaics, normal diploid blastomeres in combination with abnormal blastomeres, (III) abnormal, all nuclei
abnormal, (IV) chaotic, the chromosome constitution varies randomly from cell to cell. Approximately 25% of the embryos had
normal number of the chromosomes tested, while the majority of the embryos were abnormal. Most of the abnormal embryos were
diploid mosaics (57%). This was true for the embryos showing cleavage division as well as the embryos showing cleavage arrest.
Our data show a slightly higher incidence of abnormal embryos compared to those obtained with FISH in non-cryopreserved embryos
and confirm that the majority of preimplantation embryos fertilised in vitro contain abnormal blastomeres. The results, mechanisms, significance and implications are discussed.
Received: 19 November 1998 / Accepted: 4 March 1999 相似文献
10.
Long and short term variations in suspended particulate material: the influence on light available to the phytoplankton community 总被引:6,自引:1,他引:6
The magnitude and frequency of events leading to changes in turbidity have been studied in a large (61 km2), shallow (mean depth 3.4 m) wind-exposed lake basin at the western end of Lake Mälaren, Sweden. In this paper we couple changes in suspended particulate inorganic material (SPIM) resulting from wind driven sediment resuspension, and variations in the discharge and sediment load, to spectral variations in subsurface light and estimates of photosynthetically active radiation (PAR). To accomplish this we use a semi-analytical model which predicts the spectral variations in downwelling irradiance (E
d()) and the attenuation coefficient of downwelling irradiance (K
d()), as a function of the concentrations of chlorophyll, dissolved yellow substances, and suspended inorganic and organic particulate material. Unusually high river discharge, led to large inputs of yellow substances and large in lake yellow substance concentrations (a
ys(420) 20 m–1), causing variations in yellow substance concentration to have the greatest role in influencing temporal trends in the attenuation of PAR and variations in the depth of the euphotic zone (Z
eup). In spite of this, variations in SPIM could account for approximately 60% of the variation in Z
eup attributed to changes in yellow substances alone. Our results show that changes in suspended sediment concentration leads to both long-term and short-term changes in the attenuation of PAR, even in the presence of high concentrations of dissolved yellow substances. 相似文献