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1.

The aim of the present study is to clarify the taxonomic position of Teucrium euganeum Vis. vis à vis T.siculum (Rafin.) Guss. and T.scorodonia L. The study is based on an analysis of macro- and micro-morphological characters, type, and distribution of trichomes in different parts of the plant, chromosome counts, and a statistical analysis of such morphometric data. The results of the study allow one to consider the populations of the Euganean Hills (Padua, north-eastern Italy) as a sub-species of T.siculum, and, therefore, a new combination is proposed: Teucrium siculum (Rafin.) Guss. subsp. euganeum (Vis.) Tornadore, comb. et stat.nov.  相似文献   

2.
Abstract

This article presents results of a field survey of pollinators of two Apocynaceae, Periploca laevigata subsp. angustifolia (Labill.) Markgraf (Periplocoideae) and Caralluma europaea (Guss.) N.E.Br. (Asclepiadoideae) co-occurring on Lampedusa Island, Mediterranean sea. Fifteen species within nine families of Diptera have been identified as pollinators of the two plants. The families involved are Tephritidae, Milichiidae, Trixoscelididae, Scathophagidae, Anthomyiidae, Muscidae, Calliphoridae, Sarcophagidae, Rhinophoridae. Families of Muscidae and Sarcophagidae are the more represented, respectively with four and three species. P. laevigata subsp. angustifolia seems to have a broader spectrum of pollinators, with 12 species of Diptera involved, while C. europaea has 8 species of Diptera as pollinators. Five species of Diptera are shared between the two plant species. The presented data are the first records of pollinators for P. laevigata subsp. angustifolia and C. europaea and confirm that both taxa are fly pollinated, though they do not conform exactly to the sapromyiophilous syndrome. The number of pollinators identified indicated that the morphological and functional floral specialization of the two taxa cover a wide number of pollinators with a similar biology.  相似文献   

3.
A New, Commercially Valuable Chanterelle Species, Cantharellus californicus sp. nov., Associated with Live Oak in California, USA. The prominent golden chanterelle of California’s oak woodlands is characterized as a new species, Cantharellus californicus sp. nov., using molecular and morphological data. Our observations indicate that it is the largest Cantharellus species in the world, with individual sporocraps commonly weighing 1/2 kilogram (kg) (or 1 pound) or more when mature. Other Cantharellus species in California are compared and evaluated, including their known ectomycorrhizal hosts. The California oak chanterelle is an economically valuable species, and some observations on its commercial harvest are presented.  相似文献   

4.
Abstract

A preliminary account on some mountain lakes of the Southern Apennines. Phytoplankton investigation on three ponds of the Monte Sirino (Basilicata).—Phytoplankton standing crop and species composition have been studied in three ponds of the Southern Apennines. The observations carried out throughout ten months in 1975, showed a great number of species present in the Remmo pond, mainly diatoms, desmids, green algae, and blue-green algae. In the Sirino pond only diatoms and Chrysophyceae were present.

In comparison, in the Zapano pond, the phytoplankton was scarcely represented but the occurrence of some species of green algae may suggest a eutrophic water condition. On the basis of the peculiarities both of species composition and biomass, the major water bodies may be considered oligotrophic.  相似文献   

5.
Abstract

Embryological, systematic and ecological observations on Allium parciflorum Viv. The morphological observations and the comparison with some allied species have shown a good taxonomic isolation of Allium parciflorum: this has suggested to ascribe it to a new section.

It has been observed that the female gametophyte develops according to the disporic-type, as in other species of Allium previously studied.

The distributional area in Sardinia has been considerably extended and many ecological data are also given.  相似文献   

6.
Abstract

New species for Flora of Sardinia. — The Author remarks the presence of new species for Sardinia with some observations on the distribution and habitat.  相似文献   

7.
Abstract

L'identià dei corredi cromosomici di Centaurea Calcitrapa L. e Centaurea mncroacantha Guss. (2n = 20) ? in accordo con le vedute del Lanza, nel ritenere C. macroacantha una varietà di C. Calcitrapa.  相似文献   

8.
Abstract

Juniperus turbinata Guss. (Cupressaceae) is a threatened tree species occurring in the Mediterranean area. It is listed as a vulnerable species in the Red Book of Italian plants and its various communities are included in Annex I of the Habitats Directive 92/43/EEC as a priority habitat for conservation. During field investigations carried out to analyse the plant biodiversity of coastal habitats in southern Sicily, a new interesting population was found. This study aims to characterize this relevant new finding with a marked focus on demography and synecology of the plant community in question in order to define its habitat, assess its conservation status and propose conservation measures. Our data highlight that the juniper is characterized by low turnover population dynamics. In order to understand the role of J. turbinata in sandy soil communities of south-eastern Sicily, comparisons of 21 plots (relevés) with 25 established plots in south-eastern Sicily were carried out using cluster analysis and canonical component analysis. This has allowed three different plant communities with different ecological features to be identified.  相似文献   

9.
ABSTRACT

Cytisus aeolicus Guss, is an endemic plant restricted to the isles of Vulcano, Stromboli and Alicudi in the Aeolian archipelago. All known populations were assayed for genetic variability using enzyme polymorphism. Allozyme variation at 16 loci coding for 10 enzyme systems was examined. The great majority of loci turned out to be monomorphic or fixed heterozygous. The observed genetic depauperation is indicative of historical factors, such as the bottleneck effect associated with migration, and the founder effect in population re-establishment. The low genetic diversity is largely partitioned within rather than among populations, indicating that extant populations have not been established long enough for divergence to have occurred. The genetic uniformity, combined with the scattered distribution of small populations, and the negative shift of population size point to a critically endangered species. Strategies for conservation are considered.  相似文献   

10.
Zusammenfassung Für die Arten der GattungAira L. werden die folgenden Chromosomenzahlen mitgeteilt:A. capillaris Host, 2n=14;A. caryophyllea L., 2n=14 und 28;A. multiculmis Dum., 2n=28;A. praecox L., 2n=14;A. tenorii Guss., 2n=14;A. provincialis Jord., 2n=28 undA. cupaniana Guss., 2n=14. Die Zahlen der letzten drei Arten werden zum erstenmal veröffentlicht.Bei den diploiden Arten kommen zwei unterschiedliche Karyotypen vor: A ist verbreitet, B aufA. praecox beschränkt. Der Karyotyp der tetraploidenA. caryophyllea setzt sich aus A+B zusammen, während es sich beiA. multiculmis um eine Verdoppelung von A handelt. — Über die Verbreitung der Arten und Cytotypen werden einige Hinweise gegeben.
Two basic karyotypes in the grass genusAira L.
Summary Chromosome numbers of all known species of the genusAira L. are counted:A. capillaris Host, 2n=14;A. caryophyllea L., 2n=14 and 28;A. multiculmis Dum., 2n=28;A. praecox L., 2n=14;A. tenorii Guss., 2n=14;A. provincialis Jord., 2n=28 andA. cupaniana Guss., 2n=14. The numbers of the last three species are published for the first time. Two different karyotypes are found amongst the diploids: A is widespread, B limited toA. praecox. The karyotype of the tetraploidA. caryophyllea can be described as AB, that ofA. multiculmis as AA. — Remarks on the distribution of the species and cytotypes are added.
  相似文献   

11.
The genus Macropis Panzer 1809 includes 16 species, with the new taxon described here: M. (Sinomacropis) orientalis n. sp. The present paper is the first global revision of the genus. The authors propose a comprehensive catalogue, a key to the species and maps of some species. On the basis of an extensive morphological revision, the subgenera earlier proposed by Michenerare further discussed and assessed. Moreover, several notable range expansions are reported and discussed. The species floral choices are discussed: all the species are oligolectic on various Lysimachia species.  相似文献   

12.
13.
Abstract

In this study, using light and scanning microscopes, the morphobiometric characters of pollen grains of Bupleurum fruticosum L., B. fontanesii Guss. ex Caruel, B. gerardi All., B. lancifolium Hornem., B. semicompositum L., B. tenuissimum L. have been analysed. The elaboration of qualitative and quantitative palynological data has allowed us to formulate a key of identification which characterizes six morphotypes. Pollen grains of B. fruticosum (a perennial species) have been distinguished from the grains of the other annual species examined by us on the basis of several morphobiometric characters, a condition which has confirmed the systematic arrangements suggested by several authors. The close palynological affinity between B. tenuissimum and B. semicompositum compared with B. gerardi has supported the placement of these three species in a distinct subsect. of the sect. Eubupleura Briq. or in a distinct subsect. of the sect. Isophyllum (Hoffm.) Dumort. Similarly, our palynological data on B. fontanesii have confirmed the systematic arrangement. However, these data differ from those reported by different authors who placed the three species in the sect. Aristata Godron subsect. Juncea Briq.  相似文献   

14.
Summary

The Author points out as the Centaurea horrida Bad., an endemic thorny plant of Sardinia, presents a manifested eterophillia and tries to explain why, among the different Authors, only Moris has evidenced the characteristic; he refers some personal morphological observations on the species and concludes with a new summarized diagnosis of it.  相似文献   

15.

The cubozoan Carybdea rastonii occurs throughout the Pacific and is very abundant in areas of South Australia. C. rastonii has been observed feeding in the field on mysids and larval fish and on Anemia and fish in the laboratory. The medusae occur in swarms and are closely associated with sand patches during the day (but are not capable of attachment like C. sivickisi) and move up to the surface at dawn and dusk. The species is dioecious and the males secrete a sperm strand that may be picked up by the female. This study provides some preliminary observations on the behaviour and ecology of the cubomedusan Carybdea rastonii to stimulate further research on the mechanisms of sensory perception within the order Cubozoa. Observations on the nematocysts and the optic system are presented along with field and laboratory observations on anatomy and behaviour. The evidence for the role of vision in cubozoan behaviour is discussed.  相似文献   

16.
Summary Successful crossing is reported between L. atlanticus Gladst. (2n = 38) and L. cosentinii Guss. (2n = 32), using lines of both species selected for crossability followed by selection of relatively fertile progenies. In one cross, 82E75, from a single F2 segregating plant, 22 F3 seeds were obtained. Some other less crossable combinations were completely sterile in the f1 or F2. Backcrossing to both parent species was successful, but some crosses gave relatively more seed by using F2 plants for backcrossing rather than F2's. It is concluded that potential exists for introgression of useful genes in both directions.  相似文献   

17.
Abstract

Morphological and ecological observations on four fleshy crustose algae collected in the eulittoral and upper sublittoral zone of the Island of Gorgona: Myrionema liechtenstenii Hauck, Hildenbrandia canariensis B?rgesen, Peyssonnelia armorica (P. et H. Crouan) Weber-van Bosse in B?rgesen and Cruoria cruoriaeformis (P. et H. Crouan) Denizot are reported. For each species, information on some aspects of their ecology, geographical distribution and notes on their vegetative and reproductive morphology are given.  相似文献   

18.
Angelo Troìa 《Plant biosystems》2013,147(6):1091-1100
Abstract

Biometrical observations on Cistus salvifolius L. (Cistaceae), a species with a very variable morphology, are presented: data, collected in Sicily, are relative to three environments in which populations of Cistus salvifolius live: garigue, maquis, pinewood. Measurements are compared with other ones, found in the literature, and in some cases they disagree or supply useful indications. On the basis of the different light regimes in the three environments, and of the parameters in which the difference among the three populations is most evident, some observations about the reaction to shade in Cistus salvifolius were made. On the basis of the few data collected, the intraspecific differences were given a possible explanation with the light factor: these differences are relative to morphological parameters such as leaf area, petiole length, stem length, and also to “derived” parameters such as specific leaf area and petiole length/leaf length ratio.  相似文献   

19.
20.
SUMMARY

The plasma proteins of Cyprinus carpio (carp), Barbus holubi (yellowfish), Labeo umbratus (mudfish) and Labeo capensis (mudfish) were electrophoretically separated on polyacrylamide gels from blood samples obtained from specimens sampled during summer and winter in three different localities. Within a species, differences existed in the summer and winter plasma protein electrophoretograms from the different localities. During winter protein fraction concentration differences were found with a displacement of prominence. The results are compared between different experimental conditions and to previous observations. A genetic trait is present, but there were also alterations as a result of environmental factors.  相似文献   

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