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1.
Summary  Two new species of Euploca (Heliotropiaceae): E. krapovickasii J. I. M. Melo & Semir and E. pottii J. I. M. Melo & Semir are described for Brazil, and 12 new combinations are proposed in neotropical Euploca. Discussions of taxonomic relationships based on morphology, with illustrations and information on geographical distribution, flowering and fruiting phenology are presented.  相似文献   

2.
Mediterranean ecosystems are hotspots of species richness where fire is one of the key processes influencing their structure, composition and function. Post‐fire seedling emergence constitutes a crucial event in the life cycle of plants and species‐specific temporal and spatial patterns of seedling emergence have been hypothesized to contribute to the high diversity in these ecosystems. Here we study the temporal and spatial patterns of seedling emergence observed for the four dominant species (Cistus albidus, Ulex parviflorus, Helianthemum marifolium, Ononis fruticosa) after an experimental fire in a Mediterranean gorse shrubland. In a first analysis we compared the timing of emergence of each species using the Kaplan‐Meier method. The spatial component of seedling emergence and the spatiotemporal relationship between different cohorts of the same species were analyzed using recent techniques of spatial point pattern analyses. We found a bimodal temporal pattern of emergence. Emergence of Cistaceae species (H. marifolium and C. albidus) occurred predominantly early after the fire while Fabaceae (O. fruticosa and U. parviflorus) emerged mainly during the following autumn. Individually, all species showed an aggregated spatial pattern and, when testing for pair interactions, we found that the clusters of individual species were spatially segregated. Additionally, the clusters of individual species showed an internal spatial structure where seedlings of different cohorts were spatially segregated. Theoretical models predict that these patterns will promote species coexistence. We identified a number of mechanisms that all have the potential to contribute to the observed pattern formation. However, the potential interaction among these mechanisms are complex and not easy to predict. Our analyses take a significant step forward in studying seedling emergence in fire prone ecosystems since, to our knowledge, this is the first time that both spatial and temporal patterns of all dominant species have been studied together.  相似文献   

3.
Eight new species of Hieracium sect. Tridentata, namely H. antrorsum, H. quercifolium, H. stenianum, H. vestrogothicum, and H. vetlandaënse are described from the Götaland region (southern Sweden), H. grothii from Norrbotten in the Norrland region (northeast Sweden), and H. sparsifolium var. suppansum Johanss. and H. adampliatum var. pilosius Ohlsén are raised to specific rank as H. suppansum and H. gothiciferum respectively.  相似文献   

4.
Heterakis fieldingi n. sp. is described from Hydromys chrysogaster. It can be distinguished from Heterakis spumosa, the species it most closely resembles, in that both males and females are much smaller (4.4 and 5.1 mm, versus 9 and 13 mm, respectively for Australian specimens) and males have shorter tails (178 versus 345 m) with 9 pairs of caudal papillae compared with 10 pairs for H. spumosa. Of the species of Heterakis previously described from mammals three, H. spalacis, H. macrospiculum and H. verrucosa, are presently considered incertae sedis, a fourth has been referred to the genus Gireterakis and a fifth, H. pandei, described almost simultaneously with H. yamaguti, is considered to be synonymous with it. The remaining species are H. spumosa, H. inglisi and H. yamaguti. The presence of these four species in mammalian hosts, when all other representatives of the genus occur in grain-eating birds, cannot be explained at present.  相似文献   

5.
The taxonomic problem of cryptic species has long been recognized. Hemiboea subcapitata C. B. Clarke is a widespread and morphologically diverse species including two varieties, H. subcapitata var. subcapitata C. B. Clarke and H. subcapitata var. guangdongensis (Z. Y. Li) Z. Y. Li. However, genetic distance and molecular phylogenetic analyses based on nuclear ITS and four plastid DNA sequences (atpB‐rbcL, matK, rbcL, rpS16 intron) revealed that H. subcapitata var. guangdongensis is sister to H. subacaulis, and separated from H. subcapitata var. subcapitata, suggesting that it should be raised to the rank of an independent species as H. guangdongensis (Z. Y. Li) X. Q. Li & X. G. Xiang, comb. & stat. nov. Morphologically, the new species can be distinguished from H. subacaulis by its calyx 5‐sect from base, segments narrowly oblong‐lanceolate (versus calyx 5‐sect from base or 2‐lipped and adaxial lip 2‐lobed from below middle, segments ovate), peduncle glabrous (versus pubescent), and vermiform sclereids dispersed in leaf mesophyll (versus without sclereids).  相似文献   

6.
The results of genome analysis of five hybrids, viz.Elymus patagonicus ×Hordeum procerum, E. patagonicus ×H. tetraploidum, E. angulatus ×H. jubatum, E. angulatus ×H. lechleri, andE. angulatus ×H. parodii, are reported. The genomic constitution ofHordeum tetraploidum andH. jubatum is best given as H1H1H2H2, ofH. lechleri andH. parodii as H1H1H2H2H4H4, ofH. procerum as H1H1H2H2H3H3, and ofElymus patagonicus andE. angulatus as SSH1H1H2H2.  相似文献   

7.
Hypecoum sect.Hypecoum comprises 8 species, one with 2 additional subspecies, in the Mediterranean area and the Middle East. Five of these are recognized for the first time, viz.Hypecoum procumbens L. subsp.fragrantissimum Å. E. Dahl,H. procumbens L. subsp.atropunctatum Å. E. Dahl,H. trullatum Å. E. Dahl,H. angustilobum Å. E. Dahl andH. torulosum Å. E. Dahl. H. dimidiatum Delile andH. pseudograndiflorum Petr., which have generally been included inH. imberbe Sm., are reestablished as distinct species. Morphology and variation patterns are described and discussed with special reference to mating systems. Self-incompatibility is dominating butH. procumbens subsp.procumbens andH. torulosum are self-compatible. The broad variation ranges of the former taxon in traits presumably related to mating system (petal, anther and stigma sizes as well as pollenovule ratios) indicate varying rates of outcrossing. SEM micrographs are given of petal and stigma surfaces and of pollen grains. Chromosome counts are presented for seven taxa. All are diploid with 2n = 16.  相似文献   

8.
Abstract In the present study, the karyotypes of 34 populations belonging to 11 species and one variety of Heracleum from the Hengduan Mountains in China were examined. Chromosome numbers and the karyotypes of three species (H. souliei, H. kingdoni, and H. wenchuanense) are reported for the first time, as are the karyotypes of H. moellendorffii and H. henryi (tetraploid). Populations of H. candicans, H. franchetii, and H. kingdoni in the Hengduan Mountains were found to consist of a mixture of diploid and tetraploid plants. Except for four species of Heracleum, namely H. candicans, H. franchetii, H. henryi, and H. kingdoni, which have both diploid and tetraploid karyotypes, all other species of Heracleum are were found to be diploid. All karyotypes were found to belong to the 2A type of Stebbins, with the exception of H. candicans var. obtusifolium, which belongs to 2B, and H. hemsleyanum and H. franchetii (Mt. Dujuan, Daocheng, Sichuan, China), which belong to 1A. There was only a slight difference in the karyotype asymmetry index, which suggests a close kinship for species of Heracleum and that the entire phylogenetic development of Heracleum is relatively primitive. Species that exhibited advanced morphological features were also more advanced in karyotype structure, with the order of karyotype evolution being 1A→2A→2B. This phenomenon indicates that the species distributed in the Hengduan Mountains have not diverged completely and that the Hengduan Mountains are a relatively young and active area for the evolution of Heracleum. Polyploidization in Heracleum may be an important evolutionary mechanisms for some species, generating diversity. The biological attributes, distribution range, and the geological history of the genus have all played a part in accelerating the evolution through polyploidization or aneuploidization. It is known that as the distribution latitude of Heracleum decreases from north to south, the chromosome number, ploidy level, and asymmetry structure appear to increase. In the Hengduan Mountains, these tendencies are also evident. Finally, based on all the available cytogeographic data, we speculate that the more advanced tetraplont or aneuploid species of Heracleum in India may be derived from early diplont species that were distributed in the Caucasus region and Hengduan Mountains. The dispersal of Heracleum was from Eurasia to India, because this correlates with the emergence of the Himalayan Mountains through tectonic movement. Thus, the Hengduan Mountains are not only a center of diversity for Heracleum, but also a center of active speciation in modern times.  相似文献   

9.
Six new species of Hieracium sect. Tridentata, viz. H. piranhae, H. xanthochlorum, H. bertilssonii, H. erectiramum, H. rigescoides and H. subpardalinum are described from the Götaland region, southern Sweden and H. gothicum var. blekingense is raised to specific rank as H. blekingense.  相似文献   

10.
Two new species of Hedysarum, H. alii Haidar Ali & Qaiser sp. nov. and H. shahjinalense Haidar Ali & Qaiser sp. nov. are described from Chitral in Pakistan. As far as known, both new species are endemic to Chitral and are categorized as ‘Critically Endangered’ (CR). In addition, three other species of Hedysarum are recorded from Pakistan for the first time, viz. H. volkii Rech. f., H. brahuicum Boiss. and H. sericeum M. Bieb. These are also ‘Critically Endangered’ (CR) at a national level. A key to all 12 species of Hedysarum occurring in Pakistan is provided.  相似文献   

11.
Thirty‐three species of the lichen genus Heterodermia in South America, mainly from Ecuador and Peru, are defined. Morphology, anatomy, chemistry, habitat, distribution and interrelation between the species are discussed. A key to the treated species is presented. Five species are described as new; Heterodermia andina, H. arvidssonii, H. badia, H. fertilis and H. parva. One new combination is proposed; H. spinigera. Two species are reported as new to South America, H. spathulifera and H subcitrina, and H. palpebrata is reported as new to USA.  相似文献   

12.
Pacific coast species of the red algae Halymenia and Cryptonemia are described Of the 8 previously reported species of Halymenia 3 (H. abyssicola Dawson, H. megaspore Dawson, H refugiensis Dawson) hive been placed in synonymy with other species. Halymenia hollenbergii from southern California is described as new; H cocinea is transferred from Schizymenia (and includes Aeodes gardneri Kylin) and H. templetonii is a transfer from Weeksia. Five species of Cryptonemia are described; one of them, C. taylorii from the Revillagigedo Archipelago, as new. Wider distribution ranges are given for the remaining species, C. ovalifolia, C. obovata, C. bore alis and C. angustata. Keys to genera of the west coast Cryptonemiaceae and to the species of Halymenia and Crypronemia are provided.  相似文献   

13.
A new pinworm parasite is described from Abrocoma cinerea, a caviomorph rodent of the superfamily Octodontoidea from the Andes of Bolivia. The new species, Helminthoxys abrocomae n. sp., possesses special secretory mamelons which we consider a synapomorphy of the genus Helminthoxys.Within Helminthoxys, the closest relatives are found in octodontoid rodents: H. gigantea occurs in Octodon degus in Chile and O. bridgesiin Argentina, and H. freitasi is a parasite of Thrichomys aperoides in Brazil. H. abrocomae n. sp. differs from both other species morphometrically in relation to different parts of the body in both sexes, particularly the size of the body, spicule, gubernaculum and eggs, by the presence of a rough cuticular area around the cephalic sensory papillae and by the possession of very well-developed cervical alae which are strongly curved dorsally. H. abrocomae n. sp. is the tenth nominal species described in Helminthoxys, all of them being parasites of caviomorph rodents.  相似文献   

14.
The taxon commonly namedHelleborus viridis in Lombardy (NW. Italy) differs from both, subsp.viridis and subsp.occidentalis, and is shown to fall within the variation range ofH. odorus subsp.laxus which has been reported so far for NE. Italy only. TrueH. viridis within Italy grows only in the Maritime Alps.  相似文献   

15.
5 new taxa ofHabenaria, namelyH. bougainvillae, H. elongata R. Br. var.leptophylla, H. ensigera, H. rechingeri andH. trichoglossa, are described and illustrated, with reference to affinities to related Australian and Indo-malayan species. The occurrence in New Guinea of severalHabenaria spp. typical for a savanna-like vegetation, led to look more thoroughly at these taxa:H. elongata R. Br. andH. ochroleuca R. Br., considered so far to be endemic in Northern Australia, andH. khasiana Hook. f., hitherto only known from southeastern Asia.Studies in the subtribeHabenariinae Bentham (Orchidaceae), 2.—Part 1: Candollea34, 357 (1979).Dedicated to Hofrat Prof. DrKarl Heinz Rechinger on the occasion of his 80th birthday. — On April 30, in the year 1927, the author and his brotherOtto Renz metKarl Heinz Rechinger on a small steam-boat in a stormy Aegaen Sea, travelling from Piraeus to the Northern Sporades Islands:Karl Heinz with destination to Chelidromia, the author andO. Renz to Skopelos. By this lucky chance a lasting friendship began.  相似文献   

16.
The tropical green algal genus Halimeda is one of the best studied examples of pseudo-cryptic diversity within the algae. Previous molecular and morphometric studies revealed that within Halimeda section Rhipsalis, Halimeda incrassata included three pseudo-cryptic entities and that the morphological boundaries between H. incrassata and Halimeda melanesica were ill-defined. In this paper, the taxonomy of H. incrassata is revised: two pseudo-cryptic entities are described as new species, Halimeda kanaloana and Halimed heteromorpha, while H. incrassata is redefined to encompass a single, monophyletic entity. Similarities and differences between the three species and H. melanesica are discussed. Monophyly of H. heteromorpha, which was questioned in a former study, is reinvestigated using sets of 32 ITS1–ITS2 and 21 plastid rps3 sequences and various alignment and inference methods. The phylogenetic relationships within Halimeda section Rhipsalis are inferred from nuclear 18S–ITS1–5.8S–ITS2 and concatenated plastid sequences (tufA & rpl5–rps8–infA) and interpreted in a biogeographic context.  相似文献   

17.
18.
《Journal of bryology》2013,35(4):343-350
Abstract

The assumed European endemic Herbertus borealis differs from the closely related Holarctic species H. aduncus and H. stramineus by the convex vitta, a strongly asymmetrical leaf lamina and the dorsal lobes being much broader than the ventral ones. The latter character recurs in Asian H. delavayi and tropical American H. acanthelius. Phylogenetic analyses of nrITS sequences resolve H. borealis from the British Isles in a robust monophyletic lineage with H. delavayi from Bhutan whereas H. acanthelius is placed in a separate clade. Based on the molecular topology and morphological comparisons we propose to lower H. borealis to a synonym of H. delavayi. Accessions of H. dicranus from Africa and Asia are placed sister to a robust clade with H. delavayi, H. stramineus and H. aduncus. A sequence of H. giraldianus is nested within H. dicranus, supporting an earlier view that a synonym of the polymorphic H. dicranus is at hand. Herbertus sendtneri from Malaysia is placed sister to a clade with H. sendtneri accessions from Austria, the Azores and tropical America in a robust sister relationship. Based on this topology we deduce an Asian origin of H. sendtneri.  相似文献   

19.
The Old World Hymenostylium xanthocarpum, the generitype of Hymenostylium, was found to be unrelated to the widespread H. recurvirostrum and other species currently placed in the genus. Major distinguishing traits of H. xanthocarpum are the presence of a stem central strand, leaves broadest about midleaf and constricted just above the base, distal laminal cells usually ventrally bulging and massively unipapillose, and basal cells differentiated only in the lower 1/5–1/7 of the leaf. A new genus name, Ardeuma, is proposed for the remaining species of Hymenostylium, and combinations are made for those that are commonly recognized. A key to Tuerckheimia species in the New World that may be confused with H. xanthocarpum is provided.  相似文献   

20.
An α‐taxonomic revision of the African pike, Hepsetus odoe, from Lower Guinea is provided. The results show that three different species occur in Lower Guinea instead of one. Hepsetus akawo, recently described from West Africa, is present in the northern part of Lower Guinea; Hepsetus lineata, the most widespread species within Lower Guinea, is known from the Sanaga (Cameroon) in the north to the Shiloango (Democratic Republic of the Congo) in the south and Hepsetus kingsleyae sp. nov. is endemic to the Ogowe Basin. The new species H. kingsleyae is described and H. lineata, which is elevated here to the species level, is redescribed. Hepsetus lineata can easily be recognized by its prominent horizontal line pattern on the flanks and differs further from H. akawo and H. kingsleyae in the number of lateral‐line scales and the number of gill rakers. Hepsetus kingsleyae differs from H. lineata and H. akawo by its narrow head, elongated snout and narrow, knife‐shaped body. All three species are also distinguishable from H. odoe and the recently revalidated H. cuvieri. A few exceptional specimens could not be allocated to one of the three species and may represent hybrids because of their mixed diagnostic characters or their intermediate values.  相似文献   

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