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1.
Phylogenetic patterns, adaptations and conservation status of the rare species flora of a winter–summer rainfall ecotone in southern Africa were investigated to shed light on the species' evolutionary history and conservation requirements. Some 11% (93 species) of the Greater Fish River Canyon Landscape in Namibia were classified as rare species, more than half currently not receiving formal protection in Namibia. The rare species flora does not present a subset of the overall species pool, but a unique assemblage of plant species, over‐represented by members of the family Mesembryanthemaceae, Crassulaceae, Asphodelaceae and Hyacinthaceae. Low growth forms (dwarf leaf‐succulent shrubs, dwarf stem succulents and dwarf deciduous shrubs) as well as bulbs are more common amongst rare species. Multiple factors and processes, likely interlinked, are believed to be responsible for determining the rare species flora, indicating that individual species respond differently to the challenges posed by this arid environment. Some plants are likely remnants of wetter conditions in the past, which have retained viable populations in the mountainous terrain of this landscape, others may have evolved in situ.  相似文献   

2.
Characteristics of seven Atlantic-Mediterranean fish species are provided. Of them, four (gobies—yellow-headed Gobius xanthocephalus and red-mouthed G. cruentatus, incognito blenny Parablennius incognitus, and greater pipefish Syngnathus acus) were either first found in the Black Sea coastal zone of the Crimea, or their findings were doubted, and three species (thin-lipped grey mullet Liza ramada, European barracuda Sphyraena sphyraena, and Black Sea salmon Salmo trutta labrax) are very rare. Over the last decade, the authors recorded 15 fish species; of them, seven Atlantic-Mediterranean species have dispersed along the Crimean coasts by now, one endemic of the far eastern seas (chameleon goby Tridentiger trigonocephalus) has naturalized in Sevastopol Bay, four invading species, freshwater by origin, permanently occur in the estuary zones of the peninsula; the remaining three species are known from single findings and apparently belong to the category of accidental fish. An increase in the species composition of ichthyofauna off the Black Sea coasts of the Crimea results from the on-going process of mediterranization—the invasion in the estuary of freshwater tolerant species at the expense of accidental species that penetrated here either independently or with ballast waters.  相似文献   

3.
中国秋海棠属植物的传统利用   总被引:2,自引:0,他引:2  
秋海棠属植物除了具有较高的观赏价值外,在中国还作为药用、食用、饮料和饲料等被利用。本文应用民族植物学研究方法,通过野外调查、文献和标本收集整理和研究,共记载了中国产26种秋海棠属植物被作为药用、食用、饮料和饲料加以利用。在所记载的26种国产秋海棠属植物中,有24种作药用,8种作食用(蔬菜)或饮料,5种作饲料。3种作饮料的种类在其自然分布地被广泛利用。9种秋海棠作为多种用途加以利用,其中8种既被作为药用、食用和饮料,也被作为饲料加以利用。本研究还表明,国产秋海棠属植物中,有些种类由于过度采集利用或其它因素已变得稀有或濒危。由此提出,合理开发利用和有效保护应成为今后中国秋海棠属植物研究的重要内容。  相似文献   

4.
The untreated domestic sewage of 650,000 people and wastes from industries and ships are discharged into the inner Bay of Izmir daily. Since May 1977 physico-chemical and biological effects of pollution in the bay have been examined at 10 stations. The hydrographic studies included measurements of temperature, transparency, seston, salinity, nitrate, phosphorus and dissolved oxygen. The benthic animals collected belong to 108 species; most of them were polychaetes. Comparison of the stations reveals that species richness increases from very polluted regions towards cleaner waters.  相似文献   

5.
A total number of 40 potentially toxic microalgae and 5 taxa causing discolorations have been identified along the coasts of the Campania region (South Tyrrhenian Sea, Mediterranean Sea). This number is based on results of over 20 years of research at a coastal station in the Gulf of Naples, 4 years of monitoring activity along the Campania coasts and of a series of scattered and sporadic observations. Several species of the recently erected genera Karenia and Takayama are reported for the first time in the area. Information on the period of highest abundances or most probable period of occurrence indicates the late spring and summer as the periods of maximum risk of harmful events. Despite the variety of potentially toxic species, no human health problems nor fish kills have ever been recorded in Campania. The reasons for this apparent paradox are probably to be found in the ecological factors that regulate the abundance, toxicity and spatial distribution of the potentially harmful species and reflect as well the relatively low number of aquaculture plants in the area.  相似文献   

6.
Eokochia saxicola (Guss.) Freitag & G. Kadereit is a very rare endemic species of southern Italy and one of the rarest plants in Europe, included as priority species in the Annex II of the Council Directive 92/43/EEC. During the floristic surveys in the Cilento e Vallo di Diano National Park (Campania region, southern Italy), with the aim to assess the conservation status of rare and/or endemic species, new sites of occurrence of E. saxicola have been recorded representing the first known mainland sites; in fact, this endemic species was previously recorded only in the insular sites of Ischia (where it is extinct) and Capri in Campania region and Strombolicchio in Sicily region. Moreover, a further site was found in Capri island. So, three new sites of occurrence of E. saxicola have been recorded, increasing the total number from the two previously known to the actual five; in Campania, the total number increased from one to four. The research also increased significantly the global population size, currently made up of about 270 individuals compared with the 150 previously known. Consequences for the biogeography of the species and practical issues for conservation are discussed.  相似文献   

7.
This study provides a checklist of the Caesalpinioideae (Leguminosae) present in Equatorial Guinea, comprising 52 genera and 124 taxa. Seven species are known from Annobón, 33 from Bioko and 109 from Río Muni. The best represented genus is Senna with eight species. In addition, bibliographic references for Caesalpinioideae (Leguminosae) from Equatorial Guinea have been gathered and checked. Fourteen species are included based on literature records, because their distribution ranges suggest they may occur in Equatorial Guinea, 11 introduced species could be naturalized, and 45 taxa are recorded for the first time from the country. This represents an increase of over 35% in the floristic knowledge of Caesalpinioideae from Equatorial Guinea. A statistical summary is presented at the end of the checklist.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 541–562.  相似文献   

8.
A population of the sublittoral leopard-spotted goby, Thorogobius ephippiatus (Lowe, 1839), is recorded from Upper Loch Torridon, Scotland, and the more northerly occurrence of this Mediterranean-Atlantic species along western Scottish coasts confirmed. Modified methods of capture are described. Distinctive systematic features of this population, which tends to have low sensory papilla and pectoral ray values, are examined with reference to other T. ephippiatus and the related T. macrolepis (Kolombatovic, 1891). The time of onset and reasons for this local differentiation are discussed.  相似文献   

9.
The occurrence of Archaeopsittacus sp. (Psittaciformes) in the fossil deposits of Sansan (France) is reported, testifying to a survival of this genus in the Middle Miocene, as Archaeopsittacus verreauxi was described from the Early Miocene of Saint-Gérand-le-Puy (France) and was recorded only from its type locality. The data discussed here indicate the presence of two parrot species from Sansan, as it is the type locality of another parrot species, Pararallus dispar, only known from this locality. The differences between the humeri of these two taxa are described in detail, together with the differences from the other European fossil parrot species. The presence of more than one species of parrot in the same locality is not rare, but in Europe it is recorded in Sansan for the second time. Evidence for parrots also confirms the paleoenvironmental reconstruction of Sansan, as parrots are primarily arboreal species. Archaeopsittacus also represents one of the few common elements between the Early and Middle Miocene European bird assemblages.  相似文献   

10.
Cymbula nigra is the largest limpet in the Mediterranean. It has been listed since 1993, as an ‘endangered species’. Its historical range in the Mediterranean includes the southern Spanish, the Moroccan and the Algerian coasts. Recent observations have confirmed its proliferation in southern Spain and its progression along the European and North African Mediterranean coasts. Field surveys carried out along the Tunisian coasts during winter 2011 revealed the presence of this species in the Gulf of Tunis and the Cap Bon. The finding of C. nigra represents a range extension possibly enhanced by the current global warming, as it is a ‘warm‐water species’. The absence of records in previous surveys to the same sampling sites (2006–2007), together with the small sizes recorded in 2011, confirms the recent installation of the species. The limpet was recorded in areas spared of pollution, characterized by a predominant influence of the Atlantic current, and also showed a preference for steep cliffs exposed to strong waves. This is the first population study of this endangered gastropod outside of its original range of distribution. The determination of the ecological characteristics of newly colonized habitats might serve as a starting point for the establishment of appropriate recommendations for its conservation.  相似文献   

11.
Fish assemblages in Cais do Carvão Bay, Madeira Island, a proposed marine protected area (MPA), were determined from a diver visual census. A total of 32 transect counts were performed. Habitats sampled included sandy bottom, rocky boulders, vertical walls and rocky outcrops. Species richness, diversity, density, trophic structure, size and spatial organization were documented for the fish assemblages. Forty‐four species from 23 families were encountered; 32% belonged to Sparidae (10) and Labridae (four). The greatest species richness (25) was observed in rocky boulder habitat at 10–15 m depth, while the lowest (five) occurred over a deeper sand habitat. The greatest density (760·5 individuals per 100 m2) was recorded over rocky outcropping (20–25 m deep), and the lowest of 11·6 individuals per 100 m2 was over a sand bottom at 10–15 m depth. Thalassoma pavo , Abudefduf luridus and Chromis limbata had higher densities on hard bottoms, while Heteroconger longissimus was the most abundant species in sand bottom habitats. No significant differences were detected for all indices calculated among depth intervals for sand and rocky boulder stations. Sand and rock boulder substratum, however, differed significantly for the 10–15 m depth stratum.  相似文献   

12.
Dichotomius schiffleri Vaz-de-Mello et al is often cited as endemic to the preserved coastal sandy-dune vegetation (restinga) of Guriri Island, Espírito Santo state, and is included in the Brazilian List of Endangered Fauna as "critically endangered" (CR). However, we recorded its occurrence in twelve additional sites along the coasts of Espírito Santo, Bahia, Sergipe and Pernambuco. The geographic distribution of D. schiffleri is limited to the coastal Atlantic Forest domain, mainly in preserved restinga patches. We recommend that D. schiffleri remains in the List of Endangered species, but in the "endangered" (EN) category, according to the IUCN criteria.  相似文献   

13.
This study provides an updated catalogue of non-indigenous species (NIS) of polychaetes reported from the continental coasts of the Iberian Peninsula based on the available literature. A list of 23 introduced species were regarded as established and other 11 were reported as casual, with 11 established and nine casual NIS in the Atlantic coast of the studied area and 14 established species and seven casual ones in the Mediterranean side. The most frequent way of transport was shipping (ballast water or hull fouling), which according to literature likely accounted for the introductions of 14 established species and for the presence of another casual one. To a much lesser extent aquaculture (three established and two casual species) and bait importation (one established species) were also recorded, but for a large number of species the translocation pathway was unknown. About 25% of the reported NIS originated in the Warm Western Atlantic region, followed by the Tropical Indo West-Pacific region (18%) and the Warm Eastern Atlantic (12%). In the Mediterranean coast of the Iberian Peninsula, nearly all the reported NIS originated from warm or tropical regions, but less than half of the species recorded from the Atlantic side were native of these areas. The effects of these introductions in native marine fauna are largely unknown, except for one species (Ficopomatus enigmaticus) which was reported to cause serious environmental impacts. In other cases, the displacement of native species or economic damages are suspected.  相似文献   

14.
Capers of commerce are immature flower buds which have been pickled either in vinegar or preserved in granular salt. Semi-mature fruits and young shoots with small leaves may also be pickled for use as a condiment. The use of capers can be traced to the prehistory. Although Capparis spinosa from the western Mediterranean is the most widely used species, the subgenus comprises 23 species and subspecies occupying large territories from the Atlantic coasts to the Pacific in the Old World. We have recorded medicinal and food uses for 19 species.  相似文献   

15.
The recently described, terricolous and corticolous, sorediate lichen Lecanora flavoleprosa (belonging to the L. symmicta group) is for the first time recorded from the Carpathians. So far, this rare European species has only been reported from a few localities in the Austrian and Swiss Alps, and Fennoscandia (Norway and Sweden). In this paper several records from the Polish and Slovak Tatra Mts are presented, most of them found recently, but a few also discovered during revision of old material collected by Z. Tobolewski. The ecology and chemistry of the taxon, and differences from related sorediate Lecanora species are briefly discussed.  相似文献   

16.
The non-indigenous caprellid Caprella scaura Templeton, 1836, native to the western Indian Ocean, was firstly recorded in the Mediterranean Sea in 1994, and all Mediterranean populations discovered to date are related to shoreline areas. A total of ten fish farms were sampled off the coasts of Spain (4), Italy (1), Croatia (2), Greece (1) and Malta (2). This is the first time that C. scaura has been reported from off-coast areas. Reproducing populations have been detected in fouling communities of three tuna farms off the coast of Croatia and Malta, which also signifies the first confirmed record of this species in both countries. The occurrence of successfully established and thriving populations of C. scaura Templeton, 1836 at floating off-coast fish farms underlines the importance of these structures as stepping stones in the species.  相似文献   

17.
Sparids are a group of demersal perciform fish of high commercial value, which have experienced an extensive radiation, particularly in the Mediterranean, where they occupy a variety of different niches. The present study focuses on two species: Diplodus sargus and D. puntazzo, presenting a wide distribution from the Mediterranean to the eastern Atlantic coasts. They display similar ecological behaviour and are evolutionary closely related. Both are highly appreciated in fisheries and D. puntazzo is currently under domestication process. However, little is know on their population structure and it is an open question whether any genetic differentiation exists at the geographic level. To address this issue we examined sequence variation of a portion of the mitochondrial DNA (mtDNA) control region in population samples of each of the two species collected over a wide geographic range. In addition to the mtDNA, analysis of nuclear loci (allozymes) was included in the study to compare patterns revealed by nuclear and mitochondrial markers. The studied samples covered an area from the eastern Mediterranean to the Portuguese coasts immediately outside the Gibraltar Strait. The two species revealed a level of sequence polymorphism remarkably different for the control region with the D. puntazzo and D. sargus showing 111 and 28 haplotypes, respectively. Such a difference was not detected with allozyme markers. The two species also showed large differences in their population structure. While D. puntazzo presented a marked genetic divergence between the Atlantic and Mediterranean samples, D. sargus showed little intraspecific differentiation. These results were supported using both mtDNA and allozyme markers, and were interpreted as the consequence of differences in the history of the two species such as fluctuations in the effective population size due to bottlenecks and expansions, possibly combined with present-day differences in levels of gene flow.  相似文献   

18.
法老鱼科(Anotopteridae)物种是一类凶猛的肉食性鱼类,主要分布在北太平洋、北大西洋和南冰洋中高纬度的寒冷海区,共有1属3种,以往在中国海域没有记录。我们在整理20世纪80年代初采自中国南海的馆藏鱼类标本时,发现了该科1种,即尼氏法老鱼(Anotopterus nikparini Kukuev)。其主要特征为,体甚柔软而细长,近圆筒形。口裂大,上下颌延长,上颌具1行短齿;腭骨有1行镰刀状的大型齿;下颌有1行扁薄的大齿。鳃裂甚宽,鳃膜不与颊部相连;鳃耙退化。鳃盖骨扁薄而柔软。体表无鳞。背鳍缺失,脂鳍发达。各鳍无棘,臀鳍15,胸鳍14,腹鳍11。侧线完全,有侧线孔85。脊椎骨80。法老鱼科、法老鱼属(Anotopterus)和尼氏法老鱼是中国鱼类的新纪录科、新纪录属和新纪录种。标本保存于上海海洋大学鱼类标本馆。  相似文献   

19.
This paper identifies the Exogoninae (Syllidae) from the Mexican Caribbean coasts and includes a key to identify all the species recorded from the Grand Caribbean Sea. The classification of the family and the composition of Exogoninae are briefly examined; the correct names of the subfamilies are Syllinae Grube, 1850, Eusyllinae Malaquin, 1893, Autolytinae Malaquin, 1893 and Exogoninae Langerhans, 1879. Exogoninae includes Anguillosyllis Day, 1963, Brania de Quatrefages, 1866, Braniella Hartman, 1963, Exogone ?rsted, 1845, Exogonella Hartman, 1961, Exogonoides Day, 1963, Parapionosyllis Fauvel, 1923, Psammosyllis Westheide, 1990, Spermosyllis Claparède, 1864, and Sphaerosyllis Claparède, 1863. Pseudexogone Augener, 1922, formerly included in the group, is not a syllid; it belongs to Pilargidae. We collected 814 specimens belonging to 3 genera, 3 subgenera and 13 species as Brania (4), Exogone (4) and Sphaerosyllis (5); five new species are described: Brania russelli n. sp, Brania uebelackerae n. sp, Brania westheidei n. sp., Exogone (Exogone) bondi n. sp. and Exogone (Parexogone) sanmartini n. sp. For each species, selected references, diagnostic features, observations on morphological variability, distribution and illustrations are provided; new species also have an english diagnosis. Most abundant species were B. uebelackerae n. sp. (295), S. taylori Perkins (169), E. (E.) dispar Webster (76), and E. (E.) bondi n sp. (72).  相似文献   

20.
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