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1.
A new species of Holcus L. (Poaceae), endemic to the Azores archipelago (Portugal), is described. The vegetative and reproductive structures were studied. The diagnostic characters were compared with those of closely related species. New chromosome counts in Holcus azoricus M. Seq. & Castrov. (2 n  = 35) and H. rigidus Hochst. (2 n  = 28) are included. A possible hybrid origin is hypothesized; the potential parents are H. lanatus L. and H. rigidus .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 259–267.  相似文献   

2.
In order to deepen our knowledge of the dietary habits of the prehispanic inhabitants of El Hierro, we have determined bone strontium (Sr), manganese (Mn), magnesium (Mg), copper (Cu), zinc (Zn), and calcium (Ca) in 52 human tibiae (23 belonging to males and 20 to females individuals) buried in a single burial cave; in 21 modern individuals who served as controls; and in 11 bones of herbivores found at archeological sites of the Canary Islands. Results suggest that females consumed a more vegetarian diet, although site-corrected Sr/Ca ratio of both males and females speaks for a mixed-diet consumption.  相似文献   

3.
In order to deepen our knowledge of the dietary habits of the prehispanic inhabitants of El Hierro, we have determined bone strontium (Sr), manganese (Mn), magnesium (Mg), copper (Cu), zinc (Zn), and calcium (Ca) in 52 human tibiae (23 belonging to male and 20 to female individuals) buried in a single burial cave; in 21 modern individuals who served as controls; and in 11 bones of herbivores found at archeological sites of the Canary Islands. Results suggest that females consumed a more vegetarian diet, although site-corrected Sr/Ca ratio of both males and females speaks for a mixed-diet consumption.  相似文献   

4.
The pollen content of 31 honey samples from 19 different apiaries of El Hierro (Canary Islands) were subject to qualitative and quantitative melissopalynological analysis. The quantitative analysis demonstrated that 13% of the honey belonged to Maurizio Class I (<2?000?grains), 68% to Class II (2?000–10?000?grains) and 19% to Class III (10?000–50?000?grains). The pollen density ranges from 1?042?grains/g of honey to 24?478?grains/g with an average of 7?471?grains/g. According to the qualitative analysis, six honeys were typified as unifloral and 25 as multifloral. The unifloral honey samples were broken down as follows: two of heather (Erica arborea L.), two of Chamaecytisus proliferus (L. f.) Link‐type (“tagasaste”), one of Fabaceae (Genisteae sp.) and one of Lamiaceae Origanum vulgare L. ssp. virens (Hoffmanns. &; Link) Ietsw.‐type (thyme: Micromeria hyssopifolia Webb &; Berthel.). Honeydew elements were practically absent. Sixty‐nine pollen types were identified belonging to 42 families. The number of pollen types range between 18 and 39 (mean of 27.42). Foeniculum vulgare Mill.‐type pollen is present in all the samples. Galactites tomentosa Moench‐type, Echium plantagineum L., Echium L. sp., Bituminaria bituminosa (L.) C. H. Stirt., Chamaecytisus proliferus ‐type and Origanum vulgare ssp. virens ‐type pollen were found in 96.8% of the samples. The sensorial analysis indicated that honey types are generally of good quality, because 62% were evaluated as very high (16%), high (23%), and good (23%).  相似文献   

5.
6.
This study was performed to determine the levels of lead (Pb) and cadmium (Cd) in 63 bone samples of the prehispanic population of the island El Hierro, comparing them with the values obtained on 98 prehispanic samples from Tenerife, Fuerteventura, Gran Canaria, and La Palma, all of them in the Canary Islands, and with eight modern samples who served as controls. Prehispanic individuals from El Hierro showed the lowest bone Pb values of all the archipelago (0.72±1.01 mg/kg), significantly different (F=6.9, p<0.001) from the values obtained for the population of other islands such as Tenerife (4.87±5.36 mg/kg) or Fuerteventura (4.45±7.85 mg/kg) and also from those of the modern population (30.53±14.62 mg/kg). On the other hand, bone Cd, although slightly lower in the ancient population groups, was not significantly different when compared with the modern one. In addition, no differences were observed in bone Cd among the ancient population of the different islands. Bone lead—but not cadmium—kept an inverse significant relationship with the distance of the burial site both to south Spain (r=−0.31) and Atlantic Morocco (r=−0.28, p<0.001 in both cases).  相似文献   

7.
The Holcus complex in France consists of two species, Holcus lanatus L. (Yorkshire fog; 2n= 2x= 14) and Holcus mollis L. (Creeping soft-grass; 2n= 4x= 28) and an interspecific hybrid H.m.×H.l. (2n= 5x= 35), which is morphologically similar to Holcus mollis. A heterologous rDNA probe from wheat was used to detect the corresponding region in Holcus (s. l.) genomic DNA'fragments, for six to eight plants from 13 populations located south-west of Paris. A restriction enzyme map of the ribosomal RNA genes (rDNA) in Holcus (s. l.) was also constructed. The length polymorphism detected in the IGS region was used as a DNA fingerprint for the identification of different cytotypes and species of the Holcus complex and for the typing and delimitation of individuals in populations. In the light of the results we reconsider the assumption that the pentaploid hybrid H.m.×H.l. is purely clonal. New hypotheses concerning the origin of the pentaploid hybrid and its reproduction are proposed, and the consequences for genetic diversity in natural populations discussed.  相似文献   

8.
The trabecular bone mass (TBM) of the proximal epiphyses of right tibiae belonging to 273 prehispanic inhabitants of Gran Canaria (60. 81% males and 35.53% females) were assessed by histomorphometrical analysis of undecalcified samples and compared with that of 41 samples from El Hierro (52.63% males and 47.37% females). Among the prehispanic population of Gran Canaria 19.05% showed TBM values below 13.5% and 30.40% below 15%, although individual variability was high (range 6.71-35.4%). In sharp contrast with these results, only one case (2.44%) from El Hierro showed a TBM value below 15%, whereas mean TBM (23.50;+/- 5.60%) was significantly higher than that of the population of Gran Canaria (17.88 +/- 5.20%). The high prevalence of osteoporosis on Gran Canaria may reflect protein-calorie malnutrition. Prehistorically Gran Canaria exhibited a relatively high population density (30-40/km(2)) and a strong reliance on agriculture, in contrast with a lower population density (4/km(2)) on the island El Hierro, where the population consumed mainly marine products.  相似文献   

9.
Hieracium pallidum subsp. aetnense Gottschl., Raimondo & Di Grist. is described and illustrated. H.pallidum is considered as an intermediate species between H. schmidtii and H. racemosum (“schmidtii>racemosum”) and is placed in H. sect. Grovesiana. By consequence, H.lanudae Gottschl. is transferred to H. pallidum as H. pallidum subsp. lanudae (Gottschl.) Gottschl., Raimondo & Di Grist. A key for the three recognised subspecies of H. pallidum is provided.  相似文献   

10.
The submarine volcanic eruption occurring near El Hierro (Canary Islands) in October 2011 provided a unique opportunity to determine the effects of such events on the microbial populations of the surrounding waters. The birth of a new underwater volcano produced a large plume of vent material detectable from space that led to abrupt changes in the physical-chemical properties of the water column. We combined flow cytometry and 454-pyrosequencing of 16S rRNA gene amplicons (V1–V3 regions for Bacteria and V3–V5 for Archaea) to monitor the area around the volcano through the eruptive and post-eruptive phases (November 2011 to April 2012). Flow cytometric analyses revealed higher abundance and relative activity (expressed as a percentage of high-nucleic acid content cells) of heterotrophic prokaryotes during the eruptive process as compared to post-eruptive stages. Changes observed in populations detectable by flow cytometry were more evident at depths closer to the volcano (~70–200 m), coinciding also with oxygen depletion. Alpha-diversity analyses revealed that species richness (Chao1 index) decreased during the eruptive phase; however, no dramatic changes in community composition were observed. The most abundant taxa during the eruptive phase were similar to those in the post-eruptive stages and to those typically prevalent in oceanic bacterioplankton communities (i.e. the alphaproteobacterial SAR11 group, the Flavobacteriia class of the Bacteroidetes and certain groups of Gammaproteobacteria). Yet, although at low abundance, we also detected the presence of taxa not typically found in bacterioplankton communities such as the Epsilonproteobacteria and members of the candidate division ZB3, particularly during the eruptive stage. These groups are often associated with deep-sea hydrothermal vents or sulfur-rich springs. Both cytometric and sequence analyses showed that once the eruption ceased, evidences of the volcano-induced changes were no longer observed.  相似文献   

11.
The breeding population of Ravens on El Hierro consists of between 99 and 120 pairs. Most territories were found at altitudes of 600 metres a. s. l. or lower. Altitude had an important effect on the early stages of clutches, especially in the lower zones or in those at heights less than 900 metres a. s. l. There were no great differences in the timing of nesting in comparison with continental areas. Clutch size and breeding success were lower than in practically all continental zones, which suggests a relationship to the limited resource capacity of island ecosystems.
Zusammenfassung Auf El Hierro (Kanarische Inseln) brüten 88 bis 120 Paare Kolkraben. Die meisten Brutterritorien liegen bei 600 m ü. NN oder tiefer. Legebeginn und Bruterfolg variieren mit der Meereshöhe. Die Brutperiode weicht nicht von den Werten kontinentaler Populationen ab. Gelegegröße und Bruterfolg waren jedoch geringer als in allen bisher untersuchten kontinentalen Populationen; dies ist wahrscheinlich auf limitierte Ressourcen des Inselökosystems zurückzuführen.
  相似文献   

12.
Gloeodontia xerophila sp. nov. is described and illustrated from material collected on dead xerophyte debris in the Canary Islands. This species is characterized by the odontioid hymenophore with short aculei, up to 2 mm long, dimitic hyphal system and amyloid, subglobose and verrucose spores, 4-5 x 3-4 microm. The new taxon is compared with other species in the genus and a key to the species of Gloeodontia is provided.  相似文献   

13.
14.
Abstract:A new corticolous species of Buellia is described from La Palma and La Gomera (Canary Islands). It is mainly characterized by its strongly ornamented, (1–2)–3-septate ascospores with apical and septa thickenings, which follow an ascospore-ontogeny of type B, and its chemistry. The new species is compared with the relatedBuellia lauricassiae (Fée) Müll. Arg. and B. lauricassiaeoides Aptroot. Illustrations of the ascospores of B. laurocanariensis and B. lauricassiaeoides are presented. A habit photograph of the new species is also provided.  相似文献   

15.
Specimens of Grateloupia from Gran Canaria in the Canary Islands were used to molecularly ascertain which of the species has been used in physiological and bio-technological experiments. The rbc L sequence analysis revealed that four out of five analyzed specimens (i.e. those commonly collected for physiological research) formed a monophyletic clade with G. imbricata from Korea, Japan, and China, and were quite different from any other species of the genus. Another sample, which was associated with cage nets used for fish aquaculture, was grouped with G. lanceolata from Japan, though it appears too early as yet to identify it as such. This is, thus, proof of a new introduction of a marine macroalga, since G. imbricata is an Asian species, native to Japan and Korea, in the Canary Islands. The role of international shipping in the introduction of the species is discussed.  相似文献   

16.
Abstract

A new species of Stipa, endemic to Sicily, named Stipa valdemonensis is described here. The new taxon is related to Stipa crassiculmis. Owing to the small number of individuals observed, in few restricted localities only, it is assigned the IUCN threat status “vulnerable”.  相似文献   

17.
Lecanora sabinae sp. nov. from the Canary Islands (El Hierro and La Gomera) is characterized chiefly by its greenish thallus with abundant pruinose apothecia ranging in colour from light yellow to almost black. It contains usnic acid, zeorin, and an unknown chemical product SAB-1, is by preference lignicolous and lives in association with the conifer Juniperus phoenicea.  相似文献   

18.
在标本室研究和野外考察的基础上,对中国野青茅属的一些种类进行了修订。首次归并了5个类群,即将Deyeuxia pulchella var. laxa P.C.Kuo et S.L. Lu,D.gyirongensis P.C. Kuo et S.L.Lu,Calamagrostis megalantha Keng ex Keng f.并入 D. pulchella (Griseb.)Hook.f.作为异名;将D.venusta Keng,Calamagrostis longiflora Keng ex Keng f.并入D.flavens Keng作为异名;并确认D. compacta Munro ex Hook.f.与D.holciformis (Jaub.et Spach.)Bor是同一种。  相似文献   

19.
Abstract. 1. A study was made of the oviposition sites of five leafhopper species Diplocolenus abdominalis, Recilia coronifera, Errastunus ocellaris, Elymana sulphurella (Cicadellidae) and Dicranotropic hamata (Delphacidae) on the grasses Holcus mollis and H.lanatus.
2. Experiments were made in the laboratory, each insect species being provided simultaneously with a complete plant of both Holcus species.
3. Distribution of eggs within the leaf sheath and leaf blade, and their height above ground-level, were recorded.
4. The presence and size of egg groups were noted, as well as the angle of eggs to the longitudinal axis of the leaf.
5. On the basis of comparison of the vertical distribution of the eggs with availability of plant tissues, the five species can be divided into three groups: (a) D.abdominalis and R.coronifera , (b) D.hamata and E.ocellaris , (c) E.sulphurella. Species within a group, i.e. with similar distributions of eggs, have other features separating their oviposition sites.  相似文献   

20.
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