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1.
Chromosomes of four species in three genera of Commelinaceae from China were examined. Spatholirion longifolium had 2 n  = 20. This small genus is considered to be of a possible polyploid origin based on x  = 5, a basic number shared by its closest ally, the monospecific genus Streptolirion , with its only species having 2 n  = 10. The two genera were found to be very different from each other in their karyotypic constitution. The differences in both chromosome number (2 n  = 20 vs. 10) and karyotypic constitution support their separation as two independent genera. The remaining three species, Amischotolype hispida , Porandra ramosa and P. scandens , all had 2 n  = 36. In view of the occasional occurrence of 2 n  = 18 in the African Coleotrype , a genus very close to Amischotolype and Porandra in gross morphology, these three species are all very probably polyploid based on x  = 9. The high degree of karyotypic similarity of the three genera also strongly indicates their close affinity and supports their placement in the subtribe Coleotrypinae. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 399–403.  相似文献   

2.
The scale insect genus Limacoccus and its four palm pest species are revised and all instars with sexual dimorphism are described and illustrated. A key to Limacoccus species is provided. The unique life-history of this genus with construction of a protective tunnel by the second-instar female is described. A cladistic analysis of Limacoccus and eleven representative species of Diaspididae, Halimococcidae, Phoenicococcidae and Beesoniidae, was undertaken using fifty-four traditional and new characters from first and second instars and adult females. Character polarity was determined by outgroup comparison with Margarodidae, Pseudococcidae, Eriococcidae and Asterolecaniidae as outgroups. Nine most parsimonious trees were found. Analysis of the eleven terminal taxa of the strict consensus tree using Phoenicococcidae, Halimococcidae and Diaspididae as outgroups produced one parsimonious tree. As result of this analysis, Limacoccus is believed to be a monophyletic group of characterized by seven autapomorphies and is assigned to the family Beesoniidae fam.rev. The redefined family is divided into two tribes: Beesoniini stat.nov. with genera Beesonia and Mangalorea and Limacocciini stat.nov. with the genus Limacoccus. The Beesoniidae are here regarded as a sister group of Phoenicococcidae.  相似文献   

3.
The order Anguilliformes comprises 15 families, 141 genera and 791 fish species. Eight families had at least one karyotyped species, with a prevalence of 2n = 38 chromosomes and high fundamental numbers (FN). The only exception to this pattern is the family Muraenidae, in which the eight species analyzed presented 2n = 42 chromosomes. Despite of the large number of Anguilliformes species, karyotypic reports are available for only a few representatives. In the present work, a species of Ophichthidae, Myrichthys ocellatus (2n = 38; 8m+14sm+10st+6a; FN = 70) and four species of Muraenidae, Enchelycore nigricans (2n = 42; 6m+8sm+12st+16a; FN = 68), Gymnothorax miliaris (2n = 42; 14m+18sm+10st; FN = 84), G. vicinus (2n = 42; 8m+6sm+28a; FN = 56) and Muraena pavonina (2n = 42; 6m+4sm+32a; FN = 52), collected along the Northeastern coast of Brazil and around the St Peter and St Paul Archipelago were analyzed. Typical large metacentric chromosomes were observed in all species. Conspicuous polymorphic heterochromatic regions were observed at the centromeres of most chromosomes and at single ribosomal sites. The data obtained for Ophichthidae corroborate the hypothesis of a karyotypic diversification mainly due to pericentric inversions and Robertsonian rearrangements, while the identification of constant chromosome numbers in Muraenidae (2n = 42) suggests a karyotype diversification through pericentric inversions and heterochromatin processes.  相似文献   

4.
报道了黄山地区18种木本植物的染色体数,分属于15个科中的18个属,其中14种和2个属为首次报道;同时对Aphananthe,Fortunearia,Loropetalum,Holboellia,Platycarya属的染色体数及其在分类上的意义作了简单讨论。  相似文献   

5.
Chromosome numbers and karyotypic evolution of Caraboidea   总被引:2,自引:2,他引:0  
J. Serrano 《Genetica》1981,55(1):51-60
The chromosome numbers of 136 species of the Spanish caraboid fauna were studied. The most frequent karyotypes are 2n=37 (54 species) and 2n=24 (23 species), and the chromosome number ranges from 2n=21 to 2n=69, of which 2n=69 is the highest diploid number hitherto found among the Coleoptera. It is proposed that 2n=37 is the ancestral karyotype of the division Caraboidea and the suborder Adephaga as opposed to that of the suborder Polyphaga, 2n=20. Karyotypic evolution has led to increases and decreases of this number, both tendencies having taken place in four genera. Species of ten genera show a neo-XY bivalent due to an X-autosome fusion. The thirty-three chromosome numbers of Caraboidea reveal that these Coleoptera have a remarkable karyotypical heterogeneity.  相似文献   

6.
《Nordic Journal of Botany》2008,25(1-2):41-52
This study provides a checklist of the specimens kept in the Real Jardín Botánico herbarium (MA) belonging to the family Leguminosae and collected by Sebastián Vidal in Philippines, during the period 1876 to 1887. More than 750 specimens were studied. In the subfamily Caesalpinioideae we found 39 species (14 genera); Mimosoideae 24 species (10 genera) and Papilionoideae 85 species (40 genera). Twenty six species collected by Vidal should be considered introduced in the country. Although this collection is dated from the 19th century, five species are reported for the first time from the country: Albizia splendens, Bauhinia ferruginea , Caesalpinia andamanica , Sindora coriacea and Sindora wallichii . The whole Vidal collections (series 1, 2 and M) were studied and a map of localities with coordinates is provided. A statistical summary is presented at the end of the checklist.  相似文献   

7.
255 species and 59 subspecies of fleas from 55 genera of 7 families are known from Russia, which is 30% of the Palaearctic fauna. Additionally, over 187 species of 47 genera from 7 families are known from the neighboring territories of Central and Southern Europe, Transcaucasia, Kazakhstan, Middle Asia, Mongolia, Northeast China, and Japan. 13 species of 12 genera are known only from Russia. Noteworthy is the low percent of endemic species (not more than 4%) and genera (one genus) in the Russian fauna. The principal centers of taxonomic diversity in the Palaearctic, including many endemic species and genera, lie in the Eastern Asian, Central Asian, and Turano-Iranian Subregions, outside Russia and the Euro-Siberian Subregion. The bulk of the Russian fauna is formed by the species and genera of the three largest flea families: Hystrichopsyllidae, Ceratophyllidae, and Leptopsyllidae. The family Ceratophyllidae has the greatest number of genera in the Russian fauna, and Hystrichopsyllidae, the greatest number of species. Western (Western and Western-Central Palaearctic; 84 species from 41 genera of 7 families) and Eastern (Central-Eastern and Eastern Palaearctic; 78 species from 42 genera of 6 families) species are nearly equally represented in the Russian fauna.  相似文献   

8.
Rumen protozoal diversity in the Spanish ibex (SI) was studied in males (n=4), females (n=7) and young (n=4) from the Maestrazgo (Spain) and contrasted with domestic goats (n=3; DG) of the same region. There were no differences among SI types in protozoal concentration or in the number of protozoal species. Only protozoa from the genus Entodinium were observed in SI (seven species), the highest numbers corresponding to E. damae, E. ovibos and E. parvum. DG harboured threefold more species than SI. Nine to 10 Entodinium spp. were observed, but E. ovibos was absent from the rumen of DG, and E. damae was in only one animal. E. caudatum (caudatum, dubardi and lobospinosum morphotypes) occurred in the highest percentage, and E. dubardi, E. exiguum and E. parvum were quite abundant. Four genera of the subfamily Diplodiniinae and the genera Isotricha and Dasytricha from the family Isotrichidae were detected in DG. Epidinium (two DG) and Ophryoscolex (one DG) were also observed. Denaturing gradient gel electrophoresis analysis agreed with microscopic classification, showing up to 8 and 16 bands in SI and DG samples, respectively. The three DG clustered together (similarity index over 0.84), and separately from SI (similarity index over 0.86), with only 0.58 similarity between host species.  相似文献   

9.
徐廷志   《广西植物》1985,(2):73-78
<正> 杜鹃花科(Ericaceae)为中国植物的第七大科。因此,它在中国植物地理是中国植物区系上都占有比较重要的地位。杜鹃花科共分五个亚科:杜鹃花亚科、綟木亚科,白珠树亚科、北极果亚科和乌饭树亚科。綟木亚科、白珠树亚科和北极果亚科,虽然在本科中其种类不算太多,但所含10个属,故其多样性在本科中是首屈一指的。无疑,对这三个亚科在中国的地理分布及其与其他地区的关系的讨论是有意义的。  相似文献   

10.
《Journal of bryology》2013,35(4):360-362
Abstract

The family Sematophyllaceae is a difficult family to treat in Africa because of the large number of species described without any subsequent revision or monography and, despite the many collections mentioned in this paper, only two species had previously been identified from Malawi. A total of four species in four genera (Gammiella, Mρacrohymenium, Radulina and Wijkia) are recorded in this paper, all but one new to Malawi. The two remaining genera (Sematophyllum and Trichosteleum) present additional difficulties of identification, and will be dealt with separately.  相似文献   

11.
番荔枝科的地理分布   总被引:4,自引:0,他引:4  
番荔枝科的地理分布陈伟球(中国科学院华南植物研究所,广州510650)关键词番荔枝科;地理分布THEGEOGRAPHICALDISTRIBUTIONOFTHEANNONACEAE¥ChenWeichiu(SouthChinaInstituteofBo...  相似文献   

12.
武陵山地区种子植物区系特征与性质研究   总被引:16,自引:4,他引:12  
武陵山地区位于湘鄂渝黔交界处,面积约10万km2。本文从科、属、种水平对武陵山地区种子植物区系特征和性质进行了统计分析,结果表明:(1)本区自产种子植物201科、1005属、4119种,其中裸子植物6科、19属、36种,双子叶植物166科781属、3447种,单子叶植物29科、205属、636种,含单种和少种的科和属及木本植物比较丰富;(2)本区含世界广布科40科,热带分布科91科,温带分布科70科。含种数较多的科为广布科和热带分布科,而主要特征科则是一些主产东亚(包括中国特有)的亚热带和温带分布科;(3)本区的属含我国15种分布区类型中的14种,其中以北温带分布、泛热带分布和东亚分布三类成分比较集中。中国特有属64属(占6.83%),其中不少可能就起源于本区(或)及其周围。温带分布属多于热带分布属;(4)种的地理成分有15种类型,其中绝大多数属东亚和中国特有,它们具有明显的亚热带-温带性质。中国特有种共计2682种,其中126种为本区所特有,675种为华中区特有,其他1881种则广泛分布于我国各地并大体上可分为10个亚型。种的地理成分决定了本区现代植物区系的基本特征和性质,即在旧的热带区系的基础上蜕化演变而成的温带性亚热带植物区系或亚热带山地植物区系。本区东亚成分众多,不仅是其分布中心的一部分,而且正处于东亚成分扩散和迁移的重要通道--武陵山走廊上,因此可视为东亚植物区系的一个关键地区。  相似文献   

13.
New somatic chromosome numbers for nine species eight families and eight gen era in the Sino-Japanese Region are reported here as shown in Table 1. Data of six genera are previously unknown cytologically. The bearings of these new data on the systematics and evolution of the related species, genera or families are discussed as follows: (1) Platycarya strobilacea Sieb. et Zucc. (Juglandaceae). The chromosome number of this species is 2n=24, with a basic number of x=12, which deviates from 2n=32 occurred in Juglans, Carya, Pterocarya and Engelhardtia with the basic number x= 16. The Juglandaceae appears to be fundamentally paleotetraploid, with an original basic number of x = 6 in Platycarya and x-8 in the other four genera, although secondary polyploidy occurs in Carya. Based on the remarkable morphological differences between Platycarya and the rest seven genera of the family, Manning (1978) established two subfamilies: Platycaryoideae for Platycarya and Juglandoideae for the other genera. Iljinskaya (1990), however, recently established a new subfamily: Engelhardioideae for Engelhardtia. Lu (1982) points out that because of a great number of primitive characters occurring in Platycarya, the genus could not be derived from any other extant juglandaceous taxa but probably originated with the other groups from a common extinct ancestor. The present cytological data gives support to Manning′s treatment. We are also in favor of Lu′s supposition and suggest that basic aneuploid changes, both ascending and descending, from a common ancestor with the original basic number x=7, took place during the course of early evolution of the Juglandaceae and led to the origin of taxa with x=6 and 8. Subsequent polyploidy based on these diploids occurred and brought forth polyploids of relic nature today, whereas their diploid progenitors apparently have become extinct. (2) Nanocnide pilosa Migo (Urticaceae). The chromosome number of this Chinese endemic is 2n-24, with a basic number of x=12. An aneuploid series occurs in the Urticaceae, with x--13, 12, I1, 10, 9, 8, 7, etc. According to Ehrendorfer (1976), x = 14, itself being of tetraploid origin, is the original basic number of the whole Urticales, and descending aneuploid changes took place in the early stage of evolution of the Urticaceae and Cannabinaceae. In addition to Nanocnide, x= 12 also occurs in Australina, Hesperonide and Lecanthus, and partly in Chamabainia, Elatostema, Girardinia, Pouzolzia and Urtica. (3--4) Sedum sarmentosum Bunge and S. angustifolium Z. B. Hu et X. L. Huang (Crassulaceae). The former is a member of the Sino-Japanese Region, while the latter is only confined to eastern China. The chromosome number of Sedum is remarkably complex with n=4-12, 14-16…74, etc. S. angustifolium with 2n=72 of the present report is evidently a polyploid with a basic number of x =18 (9?) Previous and present counts of S. sarmentosum show infraspecific aneupolyploidy: n = c. 36 (Uhl at al. 1972) and 2n=58 (the present report). These two species are sympatric in eastern China and are morphologically very similar, yet distinguishable from each other (Hsu et al. 1983) S. sarmentosum escaped from cultivation in the United States gardens exhibited high irregularity in meiosis (Uhl et al. 1972). Uhl (pets. comm. ) suspected strongly that it is a highly sterile hybrid. R. T. Clausen (pets. comm.) found that plants of S. sarmentosum naturalized in the American Gardens propagated by means of their long stolons and broken stem tips, and could not yield viable seeds. Hsu et al. (1983) found that some of the plants of S. sarmentosum and S. angustifolium did yield a few seeds, but other did not. These species are, therefore, by the large vegetatively apomictic. (5) Glochidion puberum (L. ) Hutch. (Euphorbiaceae). The genus Glochidion includes about 300 species, but only eigth species from the Himalayas have been studied cytologically, with n= 36 and 2n= 52, having a basic number of x= 13. The present count for the Chinese endemic G. puberum establishes the tetraploid chromosome number 2n= 64, and adds a new basic number x= 16 to the genus. (6) Orixa japonica Thunb. (Rutaceae). Orixa is a disjunct Sino-Japanese monotypic genus. Out of the 158 genera of the Rutaceae, chromosome numbers of 65 genera have hitherto been investigated, of which 42 genera are with x=9 (66.61%), some with x=7, 8 and 10, and rarely with x=13, 15, 17 and 19. The present count of 2n=34 for O. japonica may have resulted from a dibasic tetraploidy of n=8+9. (7) Rhamnella franguloides (Maxim.) Weberb. (Rhamnaceae). The chromosome number of this member of the Sino-Japanese Region is 2n= 24. with a basic number of x= 12. The basic number x= 12 also occurs in Hovenia, Paliurus, Sageretia, Ceanothus and Berchemia. Hong (1990) suggested that x= 12 in Rhamnaceae may be derived from descending aneuploidy of a paleotetraploid ancestor. (8) Sinojackia xylocarpa Hu (Styracaceae). The chromosome number of this rare Chinese endemic is 2n= 24, with a basic number of x =12, which is identical with that in Halesia and Pterostyrax, but deviates from that in Styrax (x=8). The basic number x=8 in the Styracaceae may be derived from the original basic number x=7 by ascending aneuploidy in the early stage of evolution of the family, and x=12 may be derived from polyploidy. (9) Thyrocarpus glochidiatus Maxim. (Boraginaceae). The chromosome number of this Chinese endemic species is 2n=24, with a basic number of x=12. An extensive aneuploid sequence of x = 4-12 occurs in the Boraginaceae, of which x = 8, 7 and 6 are the most common. The basic number x=12 also occurs in Cynoglossum and Mertensia. It is evident that aneuploid changes, both descending and ascending, from an ancestor with x = 7, have taken place in the primary phase of evolutionary diversification of the Boraginaceae, and subsequent polyploidy has given rise to x=15, 17 and 19 in a few genera (e. g. Amsinskia and Heliotropium). The origin of x=12 is not certain. Either it be a result of ascending aneuploidy, or a product of polyploidy on the basis of x = 6. The present authors are in favorof the latter.  相似文献   

14.
A preliminary detective survey for the hymenopteran insect fauna of Jazan Lake dam region, Southwest Saudi Arabia, was carried out for one year from January 2018 to January 2019 using mainly sweep nets and Malaise traps. The survey revealed the presence of three hymenopteran Superfamilies (Apoidea, Vespoidea and Evanioidea) representing 15 species belonging to 10 genera of 6 families (Apidae, Crabronidae, Sphecidae, Vespidae, Mutillidae, and Evaniidae). The largest number of species has belonged to the family Crabronidae is represented by 6 species under 2 genera. While the family Apidae, is represented by 2 species under 2 genera. Family Vespidae is represented by 2 species of one genus. While, the rest of the families Sphecidae, Mutillida, and Evaniidae each is represented by only one species and one genus each. Eleven species are predators, two species are pollinators and two species are parasitics. Note for each family was provided, and species was provided with synonyms and general and taxonomic remarks and their worldwide geographic distribution and information about their economic importance are also included. All species were photographed with dorsal and lateral views.  相似文献   

15.
A small (7–11 μm long) dinoflagellate with thin amphiesmal plates was isolated into culture from a water sample collected in coastal waters of Yeosu, southern Korea, and examined by LM, SEM, and TEM, and molecular analyses. The hemispheric episome was smaller than the hyposome. The nucleus was oval and situated from the central to the episomal region of the cell. A large yellowish‐brown chloroplast was located at the end of the hyposome, and some small chloroplasts extended into the periphery of the episome. The dinoflagellate had a single elongated apical vesicle (EAV) and a type E eyespot, which are key characteristics of the family Suessiaceae. Unlike other genera in this family, it had two long furrow lines, one on the episome and the other on the hyposome, and encircling the dorsal, and lateral sides of the cell body. The pyrenoid lacked starch sheaths, but tubular invaginations into the pyrenoid matrix from the cytoplasm were observed. In the TEM, the dinoflagellate was observed to have cable‐like structures (CLSs) near the eyespot but so far not observed in other dinoflagellates. The SSU rDNA sequences examined were 1.2%–5.1% different from those of other genera in the family Suessiaceae, whereas the LSU (D1‐D3) rDNA sequences of this dinoflagellate were 15.1%–31.5% different. The dinoflagellate lacked a 51‐bp fragment in domain D2 of the LSU rDNA, but it had an ~100‐bp fragment in domain D2. This feature has been found previously only in the genera Leiocephalium and Polarella, two other genera of the Suessiaceae. The molecular phylogeny and sequence divergence based on SSU, and LSU rDNA indicate that the Korean dinoflagellate holds a taxonomically distinctive position and we consider it to be a new species in a new genus in the family Suessiaceae, named Yihiella yeosuensis gen. et sp. nov.  相似文献   

16.
Nuclear genome size of conifers as measured by flow cytometry with propidium iodide was investigated, striving to collect at least a single species from each genus. 64 out of 67 genera and 172 species were measured. Of the 67 genera, 21 are reported here for the first time and the same is true for 76 species. This nearly doubles the number of measured genera and adds 50% to the number of analyzed species. Conifers have chromosome numbers in the range of n = (7)10–12(19). However, the nuclear DNA content (2C‐value) is shown here to range from 8.3 to 71.6 picogram. The largest genome contains roughly 6 × 1010 more base pairs than the smallest genome. Genome sizes are evaluated and compared with available taxonomic treatments. For the mainly (sub)tropical Podocarpaceae small genome sizes were found with a 2C‐value of only 8–28 pg, with 13.5 pg on average. For the Taxaceae 2C‐values from 23–60 pg were determined. Not surprisingly, the genus Pinus with 97 species (39 species measured here) has a broad range with 2C = 38–72 pg. A factor of 2 difference is also found in the Cupressaceae (136 species) with nuclear DNA contents in the range 18–35 pg. Apart from the allohexaploid Sequoia, ploidy plays a role only in Juniperus and some new polyploids are found. The data on genome size support conclusions on phylogenetic relationships obtained by DNA sequencing. Flow cytometry is applicable even to young plants or seeds for the monitoring of trade in endangered species.  相似文献   

17.
The number of scale insect species (Hemiptera: Coccoidea) known from Hungary has increased in the last 10 years by 39 (16.6 %), to a total of 274 species belonging to 112 genera in10 families. The family Pseudococcidae is the most species rich, with 101 species in 34 genera; Diaspididae contains 59 species in 27 genera; Coccidae contains 54 species in 27 genera; and the Eriococcidae contains 33 species in 8 genera. The other 6 coccoid families each contain only a few species: Asterolecaniidae (7 species in 3 genera); Ortheziidae (7 species in 4 genera); Margarodidae sensu lato (5 species in 5 genera); Cryptococcidae (3 species in 2 genera); Kermesidae (4 species in 1genus); and Cerococcidae (1 species). Of the species in the check list, 224 were found in outdoor conditions, while 50 species occurred only in indoor conditions. This paper contains 22 species recorded for the first time in the Hungarian fauna.  相似文献   

18.
栌菊木属及白菊木属的细胞学研究   总被引:6,自引:3,他引:3  
对栌菊木属及白菊木属的染色体数目进行了首次报道,对栌菊木(Nouelia insignis Franch.)分布区内的10个居群进行了细胞学研究,染色体数目均为2n=54。白菊木属在中国分布的仅白菊木(Leucomeris decora Kurz)一种,对漾濞这个居群的细胞学研究表明,染色体也为2n=54。这两个属的基数可能x=9,它们可能为6倍体,结合帚木菊族已有染色体报道及形态特征,地理分布等初步分析表明:栌菊木种内分化程度小,是一自然类群;栌菊木和白菊木可能有着较近缘的联系;栌菊木可能是古老孑遗植物的后裔,为适应环境而多倍体化,得以保存下来。  相似文献   

19.
Abstract:  A recent collection of actinopterygian fossil fishes from a previously unreported locality in the Cenomanian or Turonian of southeastern Morocco includes a single specimen of a macrosemiid fish. Macrosemiids are more common in Jurassic and Early Cretaceous deposits, with the previously known range of the family being Late Triassic through Aptian or Albian. This discovery therefore extends the temporal range of the family into the Late Cretaceous. Moreover, macrosemiids had not previously been reported from northern Africa or the Moroccan area of the Tethys basin; therefore, this fossil also increases the geographical range of the family. The Moroccan macrosemiid is described in a new genus and species, Agoultichthys chattertoni . A phylogenetic analysis places it basal to all other genera of the family with the exception of Notagogus . Diagnostic characters of the new species include the high number of scales laterally along the body and the greater number of dorsal fin rays than in other members of the family.  相似文献   

20.
新疆、青海和四川等地区小麦族植物的细胞学观察   总被引:7,自引:1,他引:6  
本文对采集于新疆、青海和四川等地的小麦族(Triticeae Dumortier)10属、52种、370份种子材料进行了细胞学观察。该地区小麦族各属种的染色体数目变化范围是从2n=14到2n=84,前者主要存在于大麦属(Hordeum)、新麦草属(Psathyrostachys)和黑麦属(Secale),而后者全部集中于赖草属(Leymus)。其中染色体数目为2n=28和2n=42的类型出现的频率很高,大多存在于鹅观草属(Roegneria)和披碱草属(Elymus)。除个别种内存在不同倍性的细胞型外,绝大多数种的染色体数目非常稳定。在所有的样本中均没有观察到具非整倍体和B-染色体的材料。  相似文献   

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