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1.
The genus Ripogonum J. R. et G. Forst. is usually included in either the Smilacaceae or Liliaceae, but it has been accorded family rank. A numerical taxonomic study of the phenetic relationships of Ripogonum and all genera of the Smilacaceae, Dio-Scoreaceae, Petermanniaceae, Philesiaceae and Luzuriagaceae has been undertaken in terms of 56 characters. The results support the view that Ripogonum is only distantly related to either Smilacaceae or Dioscoreaceae and instead has affinities with Luzuriagaceae. None-the-less Ripogonum merits family status and so Ripogona-ceae are formally validated.  相似文献   

2.
中国秋海棠属等翅组植物订正   总被引:1,自引:0,他引:1  
根据海南秋海棠 (BegoniahainanensisChunetF .Chun)、多花秋海棠 (B sinofloribundaL .J.Dorr)及一新种———长柄秋海棠 (B sublongipesY .M .Shui)的特征比较 ,订正了中国秋海棠属等翅组 [Sect Petermannia (Klotzsch)A .DC .],使该组在中国增至 3个种。  相似文献   

3.
The microscopic anatomy of the vegetative parts of Petermannia cirrhosa is described for the first time. This information lends support to the exclusion of Petermannia from the Dioscorea-ceae with which it has been tentatively associated, the vascular anatomy of the two being quite dissimilar. No satisfactory explanation of the peculiar leaf-opposed position of the tendrils (inflorescence homologues) can be offered, except that it clearly cannot be accounted for by sympodial growth. Vascular tissues in Petermannia are very unspecialized.  相似文献   

4.
Begonia pellionioides YM. Shui & WH. Chen, a new species of the genus Begonia L. (sect. Petermannia (Klotzsch) A. DC., Begoniaceae), is described and illustrated. The new species is endemic to limestone areas in Southeastern Yunnan Province, China, and is most similar to Begonia hainanensis Chun & F. Chun but distinguished by its more elongated leaves with cuneate base and acuminate to caudate apex, tepals adaxially with spiny hairs and sharply triangular capsule wings with truncate superior margin. Besides, the unknown flower morphology of previously published Begonia sublongipes YM. Shui in Begonia sect. Petermannia is described.  相似文献   

5.
In a previous study of the phylogeny of basal Hymenoptera, Vilhelmsen (2001; Zool. J. Linn. Soc . 131 : 393–442) compiled an extensive morphological data matrix for a phylogenetic analysis of basal Hymenoptera, comprising 38 hymenopteran genera. In this study, his characters are revised. This results in a cladogram whose relationships largely agree with those proposed by Vilhelmsen, except that the relationships at the base of the Hymenoptera are unresolved. The revised data matrix is expanded by 17 sawfly and three apocritan taxa. Moreover, 112 new morphological characters from different parts of the larval and adult morphology are also added to the data matrix, including 82 from a recent study of the terminal abdominal segments of male Hymenoptera. The addition of the new characters leads to Xyelidae, again, being the sister-group of all other Hymenoptera. The relationships among the sawfly families as proposed by Vilhelmsen are confirmed, except that the relationships among Syntexis , Siricidae and Xiphydriidae + Vespina are unresolved and that the monophyly of Apocrita is not convincingly supported. A separate analysis is performed which includes all extant genera of Xyelidae. The internal phylogeny of Xyelidae is determined as (( Macroxyela Megaxyela ) Xyelecia ( Xyela Pleroneura )).  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79 , 209–243.  相似文献   

6.
Journal of Ichthyology - Oocyte morphology and spermatozoa ultrastructure are studied in the representatives of the genera Parascorpaena and Scorpaenopsis. Oocytes of P. aurita and S. cirrosa are...  相似文献   

7.
Three experiments of spawning induction in shi drum, Umbrina cirrosa L., were performed in six different commercial Italian hatcheries from May to August (water temperatures: 19–29 °C; salinity: 21–37 p.p.t.). In the first experiment, 119 females (1–4.7 kg), subdivided into 29 lots, were injected with a single dose (2, 5, 8, 10, 15 and 20  μ g kg−1 body weight) of short-acting gonadotropin- releasing hormone agonist (GnRHa-S), des-Gly10,[D-Ala6]-LH-RH ethylamide. In the other two experiments, 85 females (0.7–5.8 kg), subdivided into 22 and four lots, were treated with one (40 or 80  μ g kg−1) or three doses (40  μ g kg−1) of long-acting GnRHa (GnRHa-L), respectively. GnRHa-S stimulated spawning in 69% of the 29 treated lots; the number of eggs laid reached a maximum of 130 000 and a weighted mean of 29 200 total eggs kg−1. GnRHa-L elicited a spawning response in 95% of the 22 one-dose treated lots; the number of laid eggs was higher than with GnRHa-S, reaching a maximum of 213 100 and a weighted mean of 59 400 total eggs kg−1. The yield of developing embryos in 67% of the single GnRHa-L treatments was higher (sometimes up to three times) than with GnRHa-S. Triple treatments of the four lots of females with GnRHa-L always resulted in spawning responses; the best result corresponded to a number of total laid eggs of 358 900 eggs kg−1 with a yield of 177 300 developing embryos.  相似文献   

8.
Khaosokia caricoides , D.A. Simpson, Chayam. & J. Parn., a newly discovered genus and species of Cyperaceae is described and illustrated. The genus is characterized by a narrowly paniculate dioecious inflorescence with 2–4 nodes, each of the nodes having a leaf-like inflorescence bract that exceeds the inflorescence. Spikelets in both sexes are linear-cylindric and each flower has seven perianth bristles. The nutlet was immature in the specimens examined. The photosynthetic pathway is C3. Khaosokia is endemic to limestone cliffs in peninsular Thailand; its conservation status is assessed as Vulnerable (VU B1a + 2a). It has affinities to tribes Cariceae, Dulichieae and some members of Scirpeae, but the exact nature of these relationships has yet to be determined. A revised key to the genera of Cyperaceae in Thailand is presented.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 357–364.  相似文献   

9.
Juniperus excelsa and J. thurifera are considered to originate from the same ancestor. As a result of occurring in geographically isolated refuges – J. excelsa in SE Europe and SW Asia and J. thurifera in SW Europe and NW Africa – their divergence could have taken place at the end of the Tertiary, with the climate cooling. Juniperus foetidissima occurs in SE Europe and SW Asia in territories shared with J. excelsa and is similar to and sometimes misidentified with it. The occurrence of the latter two species over the same area suggests they should be more similar to each other than to the geographically distant J. thurifera . Four populations of J. excelsa ssp. excelsa , four of J. thurifera and two of Juniperus foetidissima were examined on the basis of features of 10 cones and 10 shoots of 18–36 specimens each. Results of discrimination analysis, Mahalanobis distances and cluster analysis showed great similarity to J. excelsa and J. thurifera , while J. foetidissima was more distant. The results support the hypothesis of a common ancestor of J. excelsa and J. thurifera , but suggest another origin of J. foetidissima .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 483–495.  相似文献   

10.
The seven species of rock lobster in the genus Jasus have a fragmented circumpolar distribution, inhabiting continental or island waters of the Southern Ocean. Gene flow between nominal species is possible as the planktonic larval stages of Jasus are widely dispersed in major oceanic gyres. Restriction endonuclease analysis of mitochondrial DNA (mtDNA) from five species ( J. verreauxi, J. novaehollandiae, J. edwardsii, J. lalandii and J. tristani ) was used to assess taxa previously defined only by morphological criteria. Intraspecific mtDNA nucleotide sequence diversity was generally high (0˙33–0˙99%). An absence of episodic population bottlenecks and extinctions, attributable to a teleplanic (far wandering) and prolonged pelagic stage, may be a significant factor contributing to this variation. New Zealand ( J. edwardsii ) and Australian ( J. novaehollandiae ) populations appear to be conspecific and should be referred to as J. edwardsii ; however, a significant difference in the magnitude of mean sequence diversities between these populations may indicate restrictions to gene flow across the Tasman Sea. The genome of J. verreauxi is highly distinct from the genomes of the other species (nucleotide sequence diversity: 14˙92–16˙67%), supporting the existence of 'verreauxi' and 'lalandii' groups within Jasus . High sequence diversities separating J. edwardsii, J. lalandii and J. tristani (4˙41–7˙36%) indicates longterm reproductive isolation. Hypotheses for the evolution of 'lalandii' group Jasus , which suggest a relatively recent divergence of J. lalandii and J. tristani , are not supported by phylogenetic reconstruction. Instead, it gives systematic validity to the grouping of J. lalandii with J. edwardsii as proposed by the existing taxonomy.  相似文献   

11.
Koch, J. 1982. Some lignicolous marine fungi from Sri Lanka. – Nord. J. Bot. 2 : 163–169. Copenhagen. ISSN 0107–055X.
Twenty–seven marine fungi are reported from intertidal wood collected in the Indian Ocean at Sri Lanka. One new genus Nimbospora and two new species Nimbospora effusa and Halosarpheia bentotensis are described. A new combination Savoryella paucispora is proposed. Obervations are presented on some poorly known and interesting species.  相似文献   

12.
Hansen, P. & Kristiansen, J. 1995. Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum (Synurophyceae), three new species from Madagascar. - Nord. J. Bot. 15: 215–223. Copenhagen. ISSN 0107–055X.
Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum are described and illustrated with TEM micrographs as the first results of studies of silica-scaled chrysophytes made in Madagascar. Their taxonomical position within the genus Mallomonas (sect. Torquatae , ser. Mangoferae ) is discussed and morphological distinguishing characters are presented.  相似文献   

13.
Ortíz, S. & Oubiña, J.R. 1995. Dicoma hindana (Asteraceae), a new species from Somalia. - Nord. J. Bot. 15: 187–189. Copenhagen. ISSN 0107–055X.
A new species of the genus Dicoma (sect. Psilocoma ), from Somalia, is described. The characteristics by which it can be distinguished from related species are listed.  相似文献   

14.
The data on 31–37 allozyme loci in 21 species of nine salmonid genera are used for phylogenetic analysis by seven distance methods and several variants of cladistic analysis. Monophyletic origin for all genera and three sub-families of the Salmonidae is corroborated. The closest phylogenetic relationships are characteristic of Parasalmo and Oncorhynchus (bootstrap support is 88–99%), Brachymystax and Hucho (68–97%), and the clade ( Brachymystax + Hucho )+ Salmo (up to 85%). The patterns of phylogenetic relationships in the group Salmo-Parasalmo-Oncorhynchus are analogous to those in the group Parahucho-Hucho-Brachymystax. The position of Parahucho in phylogenetic trees of the Salmoninae is extremely unstable, although it is most likely associated with the clade ( Brachymystax + Hucho)+Salmo ) or Salvelinus. When using the out group analysis, Salvelinus appears as the earliest branch of the Salmoninae tree, whereas if the molecular clock is assumed, the basal position is occupied by Oncorhynchus. However, the latter genus is probably characterized by a substantially increased rate of molecular evolution.  相似文献   

15.
Stål, B. 1995. A synopsis of Jacquinia (Theophrastaceae) in the Antilles and South America. — Nord. J. Bot. 15: 493–511. Copenhagen. ISSN 0107–055X.
The genus Jacquinia in the Antilles and South America is revised. Twenty-two native and one introduced species are recognised. In the Greater Antilles, 11 species (six endemic) occur in Cuba, eight in Hispaniola (two endemic), five in Jamaica (two endemic), and four in Puerto Rico (none endemic). Two species (none endemic) occur in the Lesser Antilles and five (four endemic) in South America. Eighteen species are native to the Antilles and of these one, J. arborea , is shared with Central America and one, J. amzillaris , is shared with South America. No species is shared between South and Central America. One new combination, J. frutescens , is made. Several species are illustrated and distribution maps for all species are presented. A key to the species in the Antilles and South America and an index to all combinations published in Jacquinia are provided.  相似文献   

16.
17.
Sea-level rise threatens low-lying coastal ecosystems globally. In Florida, USA, salinity stress due to increased tidal flooding contributes to the dramatic and well documented decline of species-rich coastal forest areas along the Gulf of Mexico. Here, we present the results of a study of coastal forest stand dynamics in thirteen 400 m2 plots representing an elevation gradient of 0.58–1.1 m affected by tidal flooding and rising sea levels. We extended previously published data from 1992–2000 to 2005 to quantify the full magnitude of the 1998–2002 La Niña-associated drought. Populations of the dominant tree species, Sabal palmetto (cabbage palm), declined more rapidly during 2000–2005 than predicted from linear regressions based on the 1992–2000 data. Dramatic increases in Juniperus virginiana (Southern red cedar) and S. palmetto mortality during 2000–2005 as compared with 1995–2000 are apparently due to the combined effects of a major drought and ongoing sea-level rise. Additionally, coastal forest stands continued to decline in species richness with increased tidal flooding frequency and decreasing elevation. Stable isotope (H, O) analyses demonstrate that J. virginiana accesses fresher water sources more than S. palmetto . Carbon isotopes reveal increasing δ 13C enrichment of S. palmetto and J. virginiana with increased tidal flooding and decreased elevation, demonstrating increasing water stress in both species. Coastal forests with frequent tidal flooding are unable to support species-rich forests or support regeneration of the most salt-tolerant tree species over time. Given that rates of sea-level rise are predicted to increase and periodic droughts are expected to intensify in the future due to global climate change, coastal forest communities are in jeopardy if their inland retreat is restricted.  相似文献   

18.
Goblet cells in the intestine of shi drum Umbrina cirrosa showed the presence of glycoconjugates particularly rich in fucose and N-acetylglucosamine residues. They displayed also sialic acid linked to galactosyl(β1→3)N-acetylgalactosamine and to galactosyl(β1→4)N-acetylglucosamine. All the nine horseradish peroxidase-conjugated lectins employed with the only exception of GSA II marked the enterocytes supranuclear region and the cell coat; the cell coat showed a more intense reactivity toward the different lectins, particularly enhanced with the use of fucosyl specific lectins.  相似文献   

19.
20.
Chowdhery, H.J. & Pal, G.D. 1995. Pholidota pygmaea (Orchidaceae) — A new species from Arunachal Pradesh, India. — Nord. J. Bot. 15: 411–413. Copenhagen. ISSN 0107–055X.
A new species of Pholidota, P. pygmaea from Arunachal Pradesh, India is described.  相似文献   

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