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1.
Platoma abbottiana (Gymnophlaeaceae; Gigartinales), a new species of benthic red algae, is described from Isla Mejía and is the second member of this genus reported from the Gulf of California, Mexico. Vegetative anatomy and reproductive details of the carpogonial and auxiliary cell branches of the new species are described and illustrated. Geographical distributions of the seven previously described Platoma species are given. Their distinguishing morphological characteristics are compared to those of the new species. The correct time and place of valid publication of the generic name, Platoma, and some of its binomials are discussed.  相似文献   

2.
Original material of the four Senecio taxa described by A. Bertoloni has been examined, and the typification of their names is discussed. A specimen from the Monti Herbarium (kept in BOLO) and iconographies from Bonanni and Bertoloni are designated as lectotypes, whereas another specimen from the Monti Herbarium is selected as neotype. The nomenclature of the names Senecio erucifolius L., Senecio tenuifolius Jacq., Senecio delphinifolius Vahl and Senecio rupestris Waldst. & Kit. is also analysed. The names S. crinitus Bertol. and S. laciniatus Bertol. belong to S. delphinifolius [now Jacobaea delphinifolia (Vahl) Pelser & Veldkamp] and S. rupestris [now Senecio squalidus subsp. rupestris (Waldst. & Kit.) Greuter], respectively, whereas S. erraticus Bertol. and S. praealtus Bertol. are accepted as separate taxa as Jacobaea erratica (Bertol.) Fourr. and Jacobaea erucifolia subsp. praealta (Bertol.) Greuter & B.Nord., respectively.  相似文献   

3.
Abstract

A hybrid individual between two taxa from “the Purple Corolla clade of the genus Capsicum”, C. eximium × C. cardenasii (2n = 24) was found during a cytogenetic study of a population belonging to C. cardenasii cytotype 1, from Bolivia. 5S and 45S rDNA probes were located on mitotic chromosomes by fluorescent in situ hybridization. The hybrid haploid karyotype length was an average value of the two taxa; the hybrid presented 24 45S loci in the diploid complement, 18 45S sites belonged to C. cardenasii cytotype 2, and six came from C. eximium cytotype 2, although this cytotype of C. eximium has been mentioned only for Argentina. Whereas hybrids were previously reported in the purple flower group, their existence has not been cytologically corroborated. This finding constitutes the first molecular cytogenetic evidence of hybridization between two taxa from this group.  相似文献   

4.
As part of a recent revision of the genus Crambe , based on the morphological study of herbarium and cultivated material, the systematics of section Dendrocrambe DC. are reviewed here. Section Dendrocrambe (including monospecific section Rhipocrambe Svent.) is considered to comprise 14 species, all endemic to Macaronesian archipelagoes: 13 in the Canary Islands and one in the Madeira Islands. Crambe feuilleei A. Santos and C. gomerae subsp. hirsuta Prina are described here, C. fruticosa subsp. pinnatifida (Lowe) Prina & Mart.-Laborde is proposed as a new status, and a key for the identification of all taxa, as well as maps with localities of collection, are provided.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 156 , 291–304.  相似文献   

5.
6.
ABSTRACT Entre Ríos Seedeaters (Sporophila zelichi), also called Zelich's Seedeaters, White‐collared Seedeaters, and Narosky's Seedeaters, are one of the rarest birds in the Neotropics. However, doubts have been raised about the validity of this species. Therefore, I evaluated the systematic status of Entre Ríos Seedeaters based on analysis of previously unpublished vocal and habitat data. I tested four hypotheses regarding the systematic status of S. zelichi: Good Species Hypothesis (valid species), Hybridization Hypothesis (hybrid S. palustris×S. cinnamomea), Color Morph Hypothesis I (morph of S. cinnamomea), and Color Morph Hypothesis II (morph of S. palustris). The songs and preferred habitat of S. zelichi are indistinguishable from those of Marsh Seedeaters (S. palustris), and the songs of both forms have exhibited similar changes from the early 1990s to 2003–2007. In contrast, the songs and preferred habitat of Chestnut Seedeaters (S. cinnamomea) differ from those of S. zelichi. Therefore, the Good Species Hypothesis is rejected by vocalization and habitat data, the Hybrid Hypothesis is undermined by the absence of shared vocal characters and limited habitat overlap of the proposed parental forms S. cinnamomea/S. palustris, and Color Morph Hypothesis I is rejected by both song and habitat data. However, Color Morph Hypothesis II is supported by both song and habitat data. Thus, I propose that S. zelichi be considered a color morph of S. palustris.  相似文献   

7.
Species currently classified within the cyanobacterial genus Microcoleus were determined to fall into two distinct clades in a 16S rDNA phylogeny, one containing taxa within the Oscillatoriaceae, the other containing taxa within the Phormidiaceae. The two lineages were confirmed in an analysis of the 16S–23S internal transcribed spacer (ITS) region sequences and secondary structures. The type species for Microcoleus is M. vaginatus Gomont, and this taxon belongs in the Oscillatoriaceae. Consequently, Microcoleus taxa in the Phormidiaceae must be placed in separate genera, and we propose the new genus Coleofasciculus to contain marine taxa currently placed in Microcoleus. The type species for Coleofasciculus is the well‐studied and widespread marine mat‐forming species Microcoleus chthonoplastes (Mert.) Zanardini ex Gomont. Other characters separating the two families include type of cell division and thylakoid structure.  相似文献   

8.
Sphenostylis, a genus of seven species in tropical and southern Africa, includes three taxa that are used by humans. Flowers and seeds of S. schweinfurthii Harms are occasionally eaten in West Africa, and this species has potential value as a forage crop. Flowers and seeds of Sphenostylis erecta (E. G. Baker) E. G. Baker subsp. erecta are eaten in parts of Central Africa, while the roots are used medicinally and as a source of dye and fish poison. The edible tubers of S. stenocarpa (Hochst, ex A. Rich.) Harms, the African yam bean, are collected from the wild in Central and East Africa. This species is cultivated for its edible seeds in west tropical Africa and for its edible tubers in Zaire. Cultivated races of S. stenocarpa may be considered domesticated forms, since they differ from wild plants of the species in a number of morphological characteristics that are evidently the result of human selection. A list of common names for the three taxa, from throughout their ranges, is presented. Sphenostylis, un género con siete especies de las regiones sur y tropical de Africa, incluye tres taxa utilizados por humanos. Las flores y semillas deS. schweinfurthii Harms son alimento ocasional en el oeste de Africa, y la especie tiene, ademas, valor potencial como forraje. Las flores y semillas de Sphenostylis erecta (E. G. Baker) E. G. Baker subsp. erecta se comen en regiones del centro de Africa, mientras que las raíces tienen usos medicinales y son fuente de colorantes y embarbascantes. Los tubérculos comestibles de S. stenocarpa (Hochst, ex A. Rich.) Harms, la jícama Africana, se colectan de plantas silvestres en el centro y este de Africa. Esta especie se cultiva por sus semillas comestibles en el oeste de Africa tropical, y por sus tubérculos comestibles en Zaire. Las razas cultivadas deS. stenocarpa pueden ser consideradas como formas domesticadas, puesto que difieren de las plantas silvestres en muchas características morfológicas que son, evidentemente, el resultado de la selección humana. Se presenta una lista de los nombres comunes para los tres taxa a lo largo de sus rangos de distribución.  相似文献   

9.
许为斌 《广西植物》2020,40(10):1389-1392
苦苣苔科植物是个研究活跃的类群,近年来随着新类群的报道和分类系统的变动,在该科的分类学研究中,出现了不少学名的种加词的性和属名不一致或出现拼写错误的情况,虽然这些错误不影响该名称的合格发表,但还是有必要根据《国际藻类、菌物和植物命名法规》进行改正。该文就苦苣苔科植物中属名以-stigma结尾的学名、属名以-cheilos结尾的学名、根据属名词尾不容易判断出性别的学名、拼写错误的名称等问题进行了分析,并对13个不符合法规的名称予以改正。此外,还就苦苣苔科植物学名的合格发表和规范使用进行了讨论。  相似文献   

10.
Chromosome numbers and karyotypes ofSonchus oleraceus (n=16, 2n=32),S. asper (n=9, 2n=18 for subsp.asper and subsp.glaucescens, andS. microcephalus (n=15, 2n=30) are studied; for the first time their idiograms are given. Karyotypes mainly comprise small chromosomes with a degree of asymmetry 2B inS. oleraceus andS. microcephalus and 2A or 2A-2B inS. asper. No karyological differences can be pointed out betweenS. asper subspecies. Data presented support the amphiploid character ofS. oleraceus, and the origin ofS. microcephalus through a dysploid process involving the former taxon. In Iberian representatives of the genus, diagrams of karyotype asymmetry indices show a cluster grouping for species, with the detached exceptions ofS. maritimus andS. crassifolius, which spontaneously hybridize in central Spain. A review of available karyological data shows that in the evolution of the genusSonchus s.l. and relatives, the basic chromosome number x=9 has generally been maintained. Dysploidy is restricted to the seriesS. bourgeaui (n=8) —S. tenerrimus (n=7) andS. oleraceus (n=16) —S. microcephalus (n=15), evolutionarily related and included in the present subgenusSonchus. Polyploidy has been detected in a total of nine taxa ofSonchus and in the generaEmbergeria, Kirkianella, andDendroseris, being more common in peripheral regions of the distribution area of the group. Five diversification centers are proposed for the whole group, of which the Western Mediterranean area, including the Iberian Peninsula, is related to diversification of the present subgenusSonchus.  相似文献   

11.
Martínez‐Méndez, N., Mejía, O., Rocha‐Gómez, A. & Méndez‐De La Cruz, F. R. (2012) Morphological convergence and molecular divergence: the taxonomic status of Sceloporus serrifer (squamata, phrynosomatidae) subspecies. —Zoologica Scripta, 41, 97–108. The systematics of the subspecies included in Sceloporus serrifer has undergone several taxonomic and nomenclatural rearrangements. This species previously comprised two recognized subspecies, Sceloporus serrifer serrifer and Sceloporus serrifer prezygus, which inhabit contrasting habitats. In this study, we re‐evaluate the taxonomic status of both subspecies using molecular and morphological evidence. Sceloporus serrifer serrifer was recovered as a paraphyletic group, whereas S. s. prezygus was recovered as a polyphyletic group. The molecular results indicate the existence of two independent lineages that diverged at least 1.29 Myr, with the populations currently recognized as S. s. prezygus from the Cuchumatanes Mountains representing a secondary invasion of S. s. serrifer from the lowlands. The lack of meristic differences among the highland populations of different species suggests convergence in similar environments achieved by two different lineages.  相似文献   

12.
13.
Coccothrinax jimenezii M.M. Mejía & R.G. García is a Critically Endangered palm species restricted to Haiti (one population near the city of Gonaïves with 43 individuals) and the Dominican Republic (one population on the shores of Lago Enriquillo with 18 individuals). The species faces two major conservation challenges: (1) water level rise in the hypersaline Lago Enriquillo and (2) overexploitation of leaves for making brooms in Haiti. Six SSR microsatellite loci were used to access levels of genetic variation and the genetic structure of these two populations. Only the Gonaïves site had loci that deviated from Hardy–Weinberg Equilibrium (2 loci). Both populations exhibited a relatively large number of private alleles (13 in Lago Enriquillo and 14 in Gonaïves) and did not show evidence of genetic bottlenecks. Inbreeding coefficients were much larger in Gonaïves (Fis = 0.232) than in Lago Enriquillo (Fis = 0.093). We detected high genetic differentiation among these sites (Fst = 0.497) suggesting that additional taxonomic studies are needed to determine if individuals from these two sites should be recognized as belonging to two different taxa. Because of taxonomic uncertainties we recommend not to translocate individuals between sites in future conservation activities involving this species.  相似文献   

14.
An annotated checklist of Senegalia Raf. and Vachellia Wight & Arn. taxa for the Indian subcontinent is presented, following the fragmentation and retypification of the former broadly defined genus Acacia Mill. The countries encompassed by this study include Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka. All indigenous species (and a few introductions) in this region previously referred to Acacia belong to Senegalia and Vachellia. All Acacia s.s. taxa are introduced (principally from Australia) and are not included in the study. There are 22 species of Senegalia (21 indigenous, 1 introduced; representing 23 taxa) and 21 species of Vachellia (12 indigenous, 9 introduced; representing 27 taxa) currently recognized for the subcontinent. The largest country, India, has most species. This checklist complements that which was recently provided for these genera in southeast Asia and China. Two names formerly recorded for the Indian subcontinent are excluded, namely, Senegalia intsia (L.) Maslin is a nomen confusum and Acacia pennata subsp. hainanensis (Hayata) I. C. Nielsen is now known to be restricted to southern China and Vietnam. Acacia eriantha Desv. is an unresolved name. The following new combinations are made herein: Senegalia tanjorensis (Ragup., Thoth. & A.Mahad.) A.S.Deshpande & Maslin, Vachellia campbellii (Arn.) A.S.Deshp., & Maslin and V. pseudowightii (Thoth.) A.S.Deshpande & Maslin. A lectotype has been selected for Acacia pennata var. canescens Graham ex Kurz (= Senegalia pennata (L.) Maslin).  相似文献   

15.
The epipelic algae found in 9 rivers of southern Baffin Island were investigated during the 1972 growing season. The overall assemblage consisted of 240 taxa, of which 200 belonged to the Bacillariophyta and, only 17 to the Chlorophyta. Members of the Bacillariophyta accounted for S7–100% by numbers and 44–100% by volume of the algae at most localities. The dominant taxa were Achnanthes kriegeri Krasske, A. marginulata Grun., and Tabellaria flocculosa (Roth.) Kütz. The Chlorophyta comprised. 0–7% by numbers and 0–30% by volume of the algae, with Cosmarium tinctum Ralfs, Cylindrocystis spp., and Mougeotia sp. being most common. The standing crop in the different rivers commonly exceeded 8 × 106 cells/cm2 (8 × 109μ3/cm2), and a maximum growth rate of 3.2 × 105 cells/cm2/day (3.2 × 108μ/cm2/day) was observed. Temperature and light are considered important, factors in the regulation of algal numbers, while nutrient supply in the overlying water, grazing by herbivores, wave action, and flooding appeared to have little effect.  相似文献   

16.
D. E. Berube 《BioControl》1978,23(4):331-337
Strains ofTephritis dilacerata Loew andT. formosa Loew from galls onSonchus arvensis L. andS. asper (L.)Hill, respectively, could be raised reliably in the laboratory only on their host plants. Ovipositing females of both tephritids select a narrow, but different, range of bud sizes. The hatching of the eggs of both flies is synchronized with the onset of rapid but elongation in their respective host plants. Because the growth characteristics of these 2Sonchus species are different, buds of equivalent developmental stages are different average sizes, and ovipositional behavior that brings about synchronization onS. arvensis is not adapted toS. asper and vice versa. Both flies occasionally laid into the flower buds of each others host plant as well asS. oleraceus L. In these cases the buds aborted or the larvae failed to complete normal development. However, both flies appear to be preadapted to the non-host plantSonchus species in this group and host records forT. dilacerata andT. formosa suggest the existence of “host races” attacking theseSonchus species, or alternatively, the frequent occurrence of ovipositional “mistakes” involving these plants.  相似文献   

17.
Names of taxa referred to Hieracium sectt. Alpestria (including the ‘Semidovrensia group’), Foliosa and Prenanthoidea and reported from Sweden have been compiled from the literature and herbaria and all uses have been indexed. Based on this synopsis, the nomenclatural validity and legitimacy of the names are analysed. In total, the use of 75, 62 and 27 names is documented for the three sections, respectively, but it is concluded that only 37, 31 and 13 of these are validly published with available combinations at the rank of species. Whenever these sections are to be revised taxonomically, a large number of new combinations will thus have to be proposed.  相似文献   

18.
Examination of type material of Macromitrium taxa described from Madagascar has unveiled three names to be placed in synonymy. Macromitrium nanothecium var. sublaeve Thér. was found to be conspecific with Macromitrium fimbriatum (P.Beauv.) Schwägr.; Macromitrium ancistrophyllum Cardot is placed in synonymy with M. nanothecium Cardot and Macromitrium semipapillosum Thér. & P.de la Varde is placed in synonymy with Macromitrium calocalyx Müll.Hal. Lectotypification is effected for four taxa within the genus. A range extension is reported for M. nanothecium, which is recorded here as new to Tanzania.  相似文献   

19.
The spores of Syntrichia ruralis (Hedw.) F. Weber and D. Mohr., S. princeps (De Not.) Mitt., S. subulata (Hedw.) F.Weber and D.Mohr var. subulata, S. subulata (Hedw.) F.Weber and D.Mohr var. angustata (Schimp.) J.J. Amann and S. subulata (Hedw.) F.Weber and D.Mohr var. graeffii Warnst. were studied by light and scanning electron microscopy for the first time. The apertural region consists of a leptoma in all spores. All taxa of the family are uniform in their spore morphology. The spores of the five taxa are of granuloid type. The spore wall of the Pottiaceae family includes sclerine (the distinction between exine and perine may be difficult to define) and intine. The taxonomy of the genus Syntrichia is discussed on the basis of its spore morphology.  相似文献   

20.
In applied research work dealing with heat-tolerant fungi, currently classified into two groups: namely thermotolerants and thermophiles, information on levels of thermotolerance is generally scant. Cited binomials are often referred to as representatives of thermophilic taxa. The present contribution attempts to specify proper heat-tolerance levels of species cited in biotechnological papers of academic and applied research types published in the last four decades. This assessment integrates relevant available information concerning well defined thermotolerant taxa. Distinction between both groups of heat-tolerant fungi is a mean to optimize investigations of temperature-dependent physiological processes. The nomenclatural status of the binomials retrieved was also re-appraised following the International Code of Botanical Nomenclature. Articles of the code govern the legal validity of fungal names. The goal is to deter `ghost names' that have no status of any kind. Their use in the literature is not only a source of confusion but also hinders the preparation of sound reviews and reference documents. The intention was also to detect names which do not fulfill all criteria for a valid legal publication. Their status could then be validated if the taxonomic position of the fungus justifies this procedure. The taxonomic status of these thermotolerants was also re-examined following present-day knowledge of their respective genera. Integration of warranted taxonomic decisions in the literature of applied research is crucial. These decisions consider the status of a fungus as a valid species (proposed synonymies) or the nature of its generic affinities (name change). Strict application of these decisions severly reduces levels of heterogeneity regarding names used for the same organism. It also clarifies its generic affinities with other thermotolerant fungi. The present note is not an exhaustive assessment on the nomenclatural and taxonomic positions of known thermotolerant fungi, an ecological group for which a global document remains to be produced. It only deals with those taxa most commonly cited in the literature examined. Over 130 fungi are here considered. The group manifests a diversity of taxonomic characters since it includes members of the following systematic groupings: Oomycetes, Zygomycetes, Ascomycetes, anamorphic fungi and Holobasidiomycetes. Few new taxonomic synonyms and invalid binomials are introduced in the present contribution. The former concern the following taxa: Gilmaniella thermophila, Mucor thermoaerospora, Sporotrichum lignicola and Zalerion thermophylii. Three binomials proved to have no taxonomic status of any sort: Acremonium cellulophilum, Nodulisporium microsporum and N. thermoroseum. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

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