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51.
Pinus mugo (Pinaceae) in the Abruzzi Mountains: high morphological variation in isolated populations
KRYSTYNA BORATYSKA KATARZYNA MARCYSIAK ADAM BORATYSKI 《Botanical journal of the Linnean Society. Linnean Society of London》2005,147(3):309-316
Thirty-three individuals of Pinus mugo from the Abruzzian Apennines (Italy), the most isolated population of the species, were examined biometrically to verify the range of trait variation and compared with six other populations sampled in the north-eastern part of the species range. Ten needles and ten cones from each individual were measured and quantified on the basis of 31 traits. The interpopulation comparison revealed a close affinity of the Abruzzian population of P. mugo to three of the six other populations. The other three north-eastern populations, one from the Tatra Mountains and two from the Chornokhora Mountains, appeared to be different. This suggests that these populations originated from other Pleistocene centres of occurrence. The intrapopulation variation of the population from the Abruzzian Apennines is comparable with those of all six populations of P. mugo from the Sudety and Carpathian Mountains. These findings support the hypothesis that isolated but locally abundant plant populations do not necessarily show a reduction in variability resulting from isolation. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 309–316. 相似文献
52.
Drought adversely affects health and reproduction in red kangaroos (Megaleia rufa) (Desmarest). There is a significant drop in body weight in adult kangaroos, and growth rates of pouch young are depressed. In adult males both lobes of the pituitary gland decrease in size. All zones in the adrenal glands become smaller and lipid stores increase. In adult females the posterior lobe of the pituitary increases in size and, although all zones in the adrenal glands shrink the evidence suggests continued stimulation of the Zonae fasciculata and glomerulosa. The decrease in size of the adrenal glands is accompanied by cortical folding and nodulation and other structural changes. Growth curves of pouch young are shown to fit the Johnson-Schumacher curve Y = A * exp [-b/(x + k)]. The data substantiate the findings of earlier workers but suggest that anoestrous female red kangaroos suckling small young may be better adapted to withstand drought than males. 相似文献
53.
The taxonomic value of male Coccoidea (Homoptera) with an evaluation of some numerical techniques 总被引:1,自引:0,他引:1
K. BORATYSKI R. G. DAVIES 《Biological journal of the Linnean Society. Linnean Society of London》1971,3(1):57-102
The taxonomic value of characters provided by male Coccoidea is reviewed in relation to traditional classifications based on the female. Numerical methods based largely on principal component analysis are applied to the classification of some Diaspididae and the various techniques are compared and evaluated. 相似文献
54.
Byl sledován vliv stoupajících koncentrací NaHCO3 na srá?ení ?eleza v zivném roztoku jako? i na inhibici r?stu rostlin, doprovázenou chlorósou a opa?ný ú?inek Na-humátu na tyto jevy. NaHC03 zp?sobil snízení obsahu ?eleza a vzestup poměru P/Fev rostlinách; za p?itomnosti humátu v ?ivném roztoku se tento efekt nedostavil. 相似文献
55.
KATARZYNA MARCYSIAK MAGORZATA MAZUR ANGEL ROMO JOSE M. MONTSERRAT YAKOV DIDUKH KRYSTYNA BORATYSKA ANNA JASISKA PIOTR KOSISKI ADAM BORATYSKI 《Botanical journal of the Linnean Society. Linnean Society of London》2007,155(4):483-495
Juniperus excelsa and J. thurifera are considered to originate from the same ancestor. As a result of occurring in geographically isolated refuges – J. excelsa in SE Europe and SW Asia and J. thurifera in SW Europe and NW Africa – their divergence could have taken place at the end of the Tertiary, with the climate cooling. Juniperus foetidissima occurs in SE Europe and SW Asia in territories shared with J. excelsa and is similar to and sometimes misidentified with it. The occurrence of the latter two species over the same area suggests they should be more similar to each other than to the geographically distant J. thurifera . Four populations of J. excelsa ssp. excelsa , four of J. thurifera and two of Juniperus foetidissima were examined on the basis of features of 10 cones and 10 shoots of 18–36 specimens each. Results of discrimination analysis, Mahalanobis distances and cluster analysis showed great similarity to J. excelsa and J. thurifera , while J. foetidissima was more distant. The results support the hypothesis of a common ancestor of J. excelsa and J. thurifera , but suggest another origin of J. foetidissima . © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 483–495. 相似文献
56.
Phylogeny and placement of Boganiidae (Coleoptera,Cucujoidea) with a review of Australian and New Caledonian taxa 总被引:1,自引:0,他引:1
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HERMES E. ESCALONA JOHN F. LAWRENCE MAREK WANAT ADAM ŚLIPIŃSKI 《Systematic Entomology》2015,40(3):628-651
A phylogeny of the cucujoid family Boganiidae (Coleoptera) is inferred for the first time based on a parsimony analysis of 102 morphological characters (70 adult and 32 larval). The analysis resulted in a monophyletic Boganiidae divided into two main clades, Boganiinae and Paracucujinae, each supported by a series of synapomorphies. The Boganiinae genera recovered were Afroboganium Endrödy‐Younga & Crowson and Boganium Sen Gupta & Crowson, whereas Paracucujinae includes Paracucujus Sen Gupta & Crowson, Metacucujus Endrödy‐Younga & Crowson, Athertonium Crowson and the New Caledonian Dzumacium caledonicum gen.n. , sp.n. New specimen data and biological information for the Australian taxa are summarized with overviews on biogeography and comments on the fossil Jurassic Parandrexis Martynov (Parandrexidae). Two new species of Boganium, primarily from the Australian mallee are described: B. malleense sp.n. and B. medioflavum sp.n . Boganium malleense is recorded from flowers of Eucalyptus gracilis F. (Myrtaceae). Adults and larvae of Paracucujus rostratus Sen Gupta & Crowson are redescribed. Athertonium parvum Crowson is redescribed and Athertonium williamsi sp.n. is described from coastal New South Wales. Several host records for Athertonium are also presented. 相似文献
57.
Abstract: We describe Muhuarina haeretica gen. et sp. nov. from a recently discovered silicified brachiopod fauna from the Lower Carboniferous of South China. This new microproductid appears to be the oldest representative of the highly differentiated, mainly Permian, aulostegoid family Cooperinidae. The internal structure of the dorsal valve of M. haeretica is dominated by strongly developed, pronounced subperipheral ridges, which suggest support for a simple schizolophe type of lophophore. Brachial ridges, as in other productides, most probably represent an attachment area of the lophophore to the dorsal epithelium. An attempt to homologize subperipheral and brachial ridges among Cooperinidae is presented. 相似文献
58.
Alina Kacperska-Palacz Maria Jasińska El⩅bieta Anna Sobczyk Barbara WciśliŃska 《Biologia Plantarum》1977,19(1):18-26
Two soluble protein fractions were found to increase under cold treatment in winter rape plants. They were the proteins of low molecular weight, impoverished in proline and methionine residues and localized in the citosol subcellular fractions. They seem to be linked in “situ” with the hydrophobic compounds of cytoplasm. Owing to those properties, they seem to be more resistant against salt-induced aggregation which may occur at freezing or at A01GP096. 相似文献
59.
PAWEŁ JAŁOSZYŃSKI 《Systematic Entomology》2012,37(2):346-359
A new extinct species of the ant‐like stone beetle supertribe Mastigitae, Euroleptochromus sabathi gen. & sp.n. is described from Eocene Baltic amber. A phylogenetic analysis of Clidicini, with representatives of Leptomastacini and Mastigini as out‐group taxa, provided strong support for a sister‐group relationship between the Neotropical Leptochromus and the new genus. The monophyly of Clidicini is questioned because of an alternative placement of Nearctic Papusus as a sister taxon to Leptomastacini + [Clidicus + (Palaeoleptochromus + (Euroleptochromus + Leptochromus))]. A dispersal‐vicariance analysis provided three alternative scenarios for the evolution of Mastigitae; with Laurasia as the ancestral area of the supertribe, major branching events occurring within either Eurasia or Laurentia and two trans‐Beringia dispersals in Late Cretaceous and Eocene. Euroleptochromus, Palaeoleptochromus and Leptochromus share highly derived structures on postgenae and maxillary palps, probably as part of a specialised feeding or prey capture mechanism. The formation of these modifications in Clidicini is demonstrated to involve a process (traced back to the Campanian, 79 Ma) of elongation and narrowing of maxillary palps and forming a cuticular setal projection from a broadened insertion site of sensory setae. 相似文献
60.
A new genus and species of fossil scorpionflies (Mecoptera) Baltipanorpa damzeni gen. et sp.n. is described from two well‐preserved male specimens in Baltic amber (middle Eocene: Lutetian). The most characteristic feature of the new taxon is an unusually developed postnotal organ on abdominal tergum IV. This is the most extremely developed example of this organ among Mecoptera and the only observation of notal and postnotal organs among fossil scorpionflies. The following combination of characters are provided to distinguish the new genus from other Panorpidae: Sc, short; R1 and R2 two‐branched; A1 joins posterior margin of wing only at same level as fork of vein Rs; unusual shape of abdomen, abdominal segments I–IV strongly reduced, abdominal segment V elongate and widened, segments VII and VIII strongly elongate; notal and postnotal organs present, strongly developed process (postnotal organ) on tergum IV, unknown in all described extant and fossil scorpionflies. Different types of notal organs of Mecoptera are compared and their function and morphology are discussed. Morphological analysis of notal and postnotal organs in extant species permits us to conclude that B. damzeni sp.n. is characterized by the most developed and complex notal organs in all Mecoptera. 相似文献