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1.
Asplenium cornutissimum, a new species from Guangxi, southern China, is described, illustrated, and compared to three similar species: A. pulcherrimum, A. coenobiale, and A. tenuifolium. So far, the new species is known only from the limestone region in southern Guangxi, from 750–825 m. It grows exclusively in karst caves.  相似文献   

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3.
A new species of Eriotheca (Bombacoideae, Malvaceae) is described and illustrated. The species, Eriotheca bahiensis, is known only from Bahia, Brazil in southern Bahian forest (floresta pluvial dos tabuleiros) and is probably restricted to that habitat. A key including the new and morphologically similar species is also presented.  相似文献   

4.
《Bird Study》2012,59(3):378-389
ABSTRACT

Capsule: Distance sampling identified an increase in estimated population size of Common Buzzards Buteo buteo in central southern England between 2011 and 2016 of more than 50%. The rate of population growth slowed in later years.

Aims: To assess the utility of a targeted distance sampling protocol to derive seasonal and annual population estimates for Common Buzzards across an area of southern England.

Methods: We used a line transect survey methodology and multiple covariate distance sampling to assess population density and abundance of Common Buzzards in spring and autumn between 2011 and 2016 across a 2600?km2 area of central southern England.

Results: Estimated population size increased by more than 50%, from approximately 2900 to 4500 individuals, across the period in a trend similar to that shown by Breeding Bird Survey data.

Discussion: A slowing of the growth in population size of Common Buzzards in central southern England suggests that the species may be approaching carrying capacity in this area. These results also suggest that currently employed broad scale survey methodologies adequately reflect the general population trends for this species. Our data provide the first published estimates of the Common Buzzard population in central southern England derived from direct empirical assessment.  相似文献   

5.
《Plant Ecology & Diversity》2013,6(2-3):197-215
Background: Temporary ponds, an abundant habitat in the Maghreb region and notably in Morocco, have a high conservation value. However, they are mainly known from the north of the country.

Aims: The aim of this work was to characterise the vegetation of Moroccan temporary ponds along a combined gradient of latitude and anthropogenic pressure.

Methods: Eighty-five ponds distributed along a north–south gradient of 750 km were sampled. For each pond, all vegetation was surveyed (flooded and dry parts) and the local abiotic characteristics were measured during two successive hydrological cycles. The prevailing anthropogenic pressures were also identified and were attributed an impact score.

Results: Eighty-one characteristic pond species (including 17 rare species) were recorded, with several new distribution data in the southern part of the latitudinal gradient. Plant communities were related to climatic and anthropogenic factors, but mostly to local factors, such as maximum water depth and soil pH. The northern ponds (wettest macroclimate) were rich in characteristic species and rare species, while the southern (driest macroclimate) ponds were more species poor.

Conclusions: In addition to the direct impact of increasing human activity, a further reduction of the floristic richness of temporary ponds is expected due to climatic changes. This is particularly the case for characteristic species which have a high conservation value.  相似文献   

6.
The new species, Matayba obovata (Sapindaceae), from southern and southeastern Brazil is described, illustrated, and contrasted to its putatively closest relatives. Palynological characters are also described. The new species belongs to sect. Matayba. A key to identify M. obovata and related species in the Atlantic Forest is included.  相似文献   

7.
8.
Summary

The ocypodid genus Paratylodiplax was described in 1974 and contains four species, three of which are endemic to southern Africa where they form an important component of the estuarine benthic fauna. However, very little is known about the biology and ecology of the genus, with discrepancies existing between the commonly quoted distributions and actual records of the species. This comment outlines the current taxonomic status of the genus and attempts to resolve the discrepancies in the distributions of the southern African species Paratylodiplax blephariskios has been recorded from the Morrumbene estuary in Mozambique to the Mngazana estuary in the eastern Cape, while the distributions of P. algoensis and P. edwardsii are given as being from the Mngazana to the Eerste estuary and Langebaan Lagoon in the western Cape respectively.  相似文献   

9.
Background: Under climate-change scenarios, rock outcrops, by providing microclimatically diverse habitats, different from those of surrounding zonal vegetation matrix, may serve as climatic refugia and thereby facilitate the persistence of specialist species.

Aim: We tested whether rock outcrops of southern temperate latitudes could act as local refugia for a cold-adapted flora in the face of global warming.

Methods: We related species composition of 50 outcrops and that of their surrounding vegetation to climatic data at local and regional scales to establish whether species distributions reflected differences that could indicate the existence of climatic refugia.

Results: While at a regional scale, species composition of the outcrops across the study area was related to mean annual precipitation and mean annual maximum temperature, locally, southern faces of outcrops had different species and lower maximum temperatures than insolated north faces and surrounding vegetation plots.

Conclusions: South faces of outcrops by providing cool microhabitats, and currently harbouring species not found in the surrounding zonal vegetation matrix, could serve as local refugia for heat-intolerant plants and other microthermic organism. The degree of ‘stability’ of these refugia will depend on the degree of future change in climate. Therefore, it is important to plan protected area networks that maximise local environmental heterogeneity, including the protection of rock outcrops both as refugia for cold-adapted species and as potential stepping stones that would allow dispersal of these species between supportive environments through unfavourable ones.  相似文献   

10.
《Journal of bryology》2013,35(4):791-796
Abstract

Mniobryum bracteatum Bartr. from Ecuador is reduced to a synonym of Pohlia integra (Card.) Shaw, previously known only from Mexico. The species, characterized by the occurrence of rhizoidal tubers, is also recorded from Bolivia and southern Africa.  相似文献   

11.
《Journal of bryology》2013,35(4):465-474
Abstract

The distinguishing features of Lophozia subg. Protolophozia are enumerated. A key is provided for the eleven species of this primarily cool antipodal and subantarctic subgenus. Lophozia gymnocoleopsis Schust. & Engel from southern Chile is described as new. This species and L. crispata, also of southern South America, are the only representatives of subg. Protolophozia in South America. Protolophozia sect. Notolophozia and sect. Gymnocoleopsis Schust. are described as new.  相似文献   

12.
Abstract

Fifty-eight species of echinoderms (excluding holothurians) are newly recorded from the southern Norfolk Ridge and the Three Kings Rise to the north of New Zealand. Two species of Asteroidea, in the genera Ceramaster and Pseudoceramaster, ceramaster are described as new. A total of 115 species of echinoderms, not counting the holothurians, are now known from this area. They include 14 crinoids, 35 asteroids, 41 ophiuroids, and 25 echinoids.  相似文献   

13.
Until now, two species of Borgatomelissa Patiny, 2000 have been described, both from loci typici located in the Near East and eastern Africa. Borgatomelissa brevipennis (Walker, 1871), the most widespread taxon, has also been found in the southern Sahelo-Sudanian belt of the Sahara. A third species from eastern Morocco is described in the present study: Borgatomelissa flavimaura n. sp. In addition to taxonomic insights, the new species sheds a new light on the biogeography of the genus.  相似文献   

14.

The catshark genus Holohalaelurus Fowler is currently represented by five species distributed off the southern and eastern parts of the African coast. Very few parasitological records exist for any of these five species, representing a significant knowledge gap. We report the first monogenean species from the bathydemersal species Holohalaelurus regani (Gilchrist): a new species of Microbothriidae Price, 1936, Leptomicrobothrium holohalaelure n. sp. from the dorsal skin surface, and a new species of Hexabothriidae Price, 1942 representing a new genus, Scyliorhinocotyle narvaezae n. gen., n. sp., from the gill lamellae. Both monogenean records represent the first for any member of the catshark genus Holohalaelurus. Previously we focused on the identification of monogenean taxa of emerging veterinary importance for public aquaria. We now begin a focused effort to document a generally unexplored monogenean biodiversity from diverse marine habitats off South Africa.

  相似文献   

15.
《Journal of bryology》2013,35(4):579-586
Abstract

The growth of transplants of six Sphagnum species at a blanket bog site in the southern Pennines was investigated and compared with that of similar transplants of the same provenance at a site in the Berwyn Mountains, North Wales. All species made some growth in the first year at the polluted southern Pennine site, but only Sphagnum recurvum grew in the second year. All species made good growth in both years at the relatively unpolluted North Wales site. A similar result was obtained in a later transplant experiment, and after more than 3 years, Sphagnum recurvum alone survives of the original transplants in the southern Pennines. The failure of these transplants is discussed in relation to a fumigation experinlent in which Sphagnum species were subjected to concentrations of sulphur dioxide in air and sulphate in rain similar to those occurring in the southern Pennines today. It is concluded that current concentrations of sulphur pollutants may not entirely account for the failure of the transplants.  相似文献   

16.
A new species of Cremosperma (Gesneriaceae, tribe Beslerieae) is described from the Chocó floristic region of the western Andean slopes of northern Ecuador and southern Colombia. The dorsiventral shoots and strongly anisophyllous leaves differentiate Cremosperma anisophyllum from all other congeners.  相似文献   

17.
《Journal of bryology》2013,35(4):601-605
Abstract

Entodon dregeanus (Hornsch.) C.M., from Africa arid E. plicatus C.M., from southern India and Ceylon, are reduced to the synonymy of E. macropodus (Hedw.) C.M., an American species.  相似文献   

18.
A new species of Gasteranthus (Gesneriaceae, Beslerieae) is described from the eastern Andean slopes of southern Ecuador. The presence of a strongly hypocyrtoid corolla with lateral protrusions along the pouch and ternate leaves differentiate Gasteranthus diverticularis from all other congeners.  相似文献   

19.
20.
A new species of Paullinia from the Atlantic Forest of southern Bahia, Brazil, is described and illustrated. Paullinia unifoliolata belongs to sect. Pachytoechus and is distinguished by its unifoliolate leaves. In addition, micromorphological characters of the pollen grains are described, and a comparison with P. carpopoda, the most similar species, is provided.  相似文献   

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