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1.
The somatic chromosomes and karyotypes of threeNicotianeae have been studied for the first time. All of them have 2n = 2x = 22 and symmetrical karyotypes.Benthamiella pycnophylloides has 9 m pairs + 1 sm pair + 1 st pair; pairs 2, 4, 5, and 11 bear microsatellites.Combera paradoxa andPantacantha ameghinoi have 9 m pairs + 2 sm pairs; pair 11 ofC. paradoxa is satellited, while pair 9 ofP. ameghinoi bears microsatellites and shows a pericentric inversion in heterozygous state in 20% of the seedlings. Results are compared with previous chromosome reports for the tribe. The cytological data support their present position in the family system. Besides,Benthamiella, Combera andPantacantha appear to be primitive genera ofNicotianeae, a comparatively advanced tribe within the family.Chromosome studies onNicotianeae (Solanaceae) 1.  相似文献   

2.
Following the study of 28 species of Lepturinae (Coleoptera: Cerambycidae) the karyotypes of seven additional Palaearctic and one Nearctic species are established. The 19,X male karyotypes found in genera Stictoleptura (four species), Vadonia and Judolia (one species each) confirm the loss of Y chromosome in Lepturini. The 22,XY male karyotype of Cortodera humeralis is very close to that of some species of Rhagiini (genera Gaurotes, Acmaeops, Dinoptera, all 22,XY) and Grammoptera ruficornis (24,XY) recently reported. We propose that these taxa could form a monophyletic group within Rhagiini. The karyotype of the Nearctic species Desmocerus palliates (23,neoXneoXneoY) is quite different and characterized by the presence of many acrocentric chromosomes and a complex autosome–gonosome translocation. Its particular karyotype is compatible with its present classification within a separate tribe, the Desmocerini.  相似文献   

3.
The subfamily Phyllostominae comprises taxa with a variety of feeding strategies. From the cytogenetic point of view, Phyllostominae shows different rates of chromosomal evolution between genera, with Phyllostomus hastatus probably retaining the ancestral karyotype for the subfamily. Since chromosomal rearrangements occur rarely in the genome and have great value as phylogenetic markers and in taxonomic characterization, we analyzed three species: Lophostoma silvicola (LSI), Phyllostomus discolor (PDI) and Tonatia saurophila (TSA), representing the tribe Phyllostomini, collected in the Amazon region, by classic and molecular cytogenetic techniques in order to reconstruct the phylogenetic relationships within this tribe. LSA has a karyotype of 2n=34 and FN=60, PDI has 2n=32 and FN=60 and TSA has 2n=16 and FN=20. Comparative analysis using G-banding and chromosome painting show that the karyotypic complement of TSA is highly rearranged relative to LSI and PHA, while LSI, PHA and PDI have similar karyotypes, differing by only three chromosome pairs. Nearly all chromosomes of PDI and PHA were conserved in toto, except for chromosome 15 that was changed by a pericentric inversion. A strongly supported phylogeny (bootstrap=100 and Bremer=10 steps), confirms the monophyly of Phyllostomini. In agreement with molecular topologies, TSA was in the basal position, while PHA and LSI formed sister taxa. A few ancestral syntenies are conserved without rearrangements and most associations are autapomorphic traits for Tonatia or plesiomorphic for the three genera analyzed here. The karyotype of TSA is highly derived in relation to that of other phyllostomid bats, differing from the supposed ancestral karyotype of Phyllostomidae by multiple rearrangements. Phylogenies based on chromosomal data are independent evidence for the monophyly of tribe Phyllostomini as determined by molecular topologies and provide additional support for the paraphyly of the genus Tonatia by the exclusion of the genus Lophostoma.  相似文献   

4.
The major ribosomal DNA (rDNA) loci were localized on meiotic and mitotic chromosomes and in interphase nuclei of 18 ground-beetle species belonging to three tribes of the supertribe Carabitae by fluorescence in situ hybridization (FISH), using a PCR-amplified 18S rDNA as a probe. Meiotic observations indicate that the 18S rDNA sequences are located on the largest autosomal bivalent in 12 species of Carabus , two species of Calosoma (both genera belonging to the tribe Carabini), and three sibling species of Ceroglossus chilensis (tribe Ceroglossini). The data suggest the occurrence of a conservative pattern in these three genera despite the chromosomal rearrangements that have led to karyotypes with higher chromosome numbers in Ceroglossus . A different result is found in Cychrus caraboides (tribe Cychrini), where ribosomal cistrons are located in two medium-sized autosomal pairs. Further species of Cychrini should be studied for corroborating the occurrence of molecular and karyotypical apomorphies in Cychrus with regard to the genera Carabus, Calosoma and Ceroglossus .  相似文献   

5.
Banded karyotypes of 50 species belonging to 23 genera were analyzed. The diploid chromosome numbers ranged from 26 to 50. For karyotypic comparison we used a 44 chromosomes karyotype, consisting of 4 metacentric and 17 acrocentric autosomes, as “basic karyotype”. Almost all of its 25 autosomal arms could be identified in each individual karyotype. In 8 chromosomes, i. e. 1/2, 7, 11, 12, 13, 15, 23 and X, small inversions were detected. As a result, each of the chromosomes mentioned occurs in two states which differ slightly in their banding patterns. These were used as character states in the cladistic analysis together with other chromosomal rearrangements. The implications drawn from the cladogram obtained are: The Miniopterinae clearly belong to the Vespertilionidae but are the first to branch off from the common stem. The tribe Myotini should be raised to the rank of a subfamily. Within the largest subfamily Vespertilioninae, one autapomorphic chromosomal character was found for each of the tribes Vespertilionini and Pipistrellini. In addition, both tribes are distinguished from the other Vespertilioninae tribes by two synapomorphic features. These results allow for the first time an unequivocal classification of the systematically difficult “pipistrelloid” species. The species of the genus Pipistrellus (sensu Hill and Harrison 1987) are spread over the Pipistrelllni and Vespertilionini. We therefore suggest the splitting of this heterogenous genus into at least four genera. Only the members of the previous subgenus Pipistrellus constitute the genus Pipistrellus and belong to the Pipistrellini. The previous subgenera Hypsugo, Vespadelus and Falsistrellus, given generic rank in some recent studies, belong to the tribe Vespertilionini and are not closely related to Pipistrellus. For the genera Eptesicus and Hesperoptenus, which belong neither to the Vespertilionini nor to the Pipistrellini, the tribe Eptesicini was established. The phylogenetic relations of this tribe and the status of the presumably polyphyletic tribe “Nycticeiini” could not be solved.  相似文献   

6.
Chromosome numbers and karyotypes of species from four American Zamiaceae (Cycadales) are reported. Zamia shows interspecific and intraspecific chromosome variation, whereas Microcycas, Ceratozamia, and Dioon have constant karyotypes within each genus. In Zamia, all karyotypes have the same number of submetacentric and acrocentric chromosomes, but they differ in the number of metacentric and telocentric chromosomes. Centric fission of metacentric chromosomes is proposed to explain the karyotypic variation in this genus. Zamia shows karyological relationships with Microcycas and Ceratozamia, whereas Dioon appears very distinct from the other American cycad genera. Affinity among Zamia, Ceratozamia, and Microcycas karyotypes and distinctiveness of Dioon karyotypes are supported by comparative analysis of phenotypic characters in the four genera.  相似文献   

7.
The Vernonieae tribe presents strong taxonomic delimitation problems as it is considered one of the most complex groups of the Asteraceae family, comprising approximately 1100 species distributed across 129 genera. In this study, a comparative analysis of the Vernonieae species was performed to understand the events involved in the chromosome evolution of these species and to further deduce their taxonomy. The representatives were cytogenetically characterized via analyses of morphology, karyotype asymmetry and differential staining with fluorochromes CMA and DAPI as well as FISH. According to morphometric data, all species showed symmetrical karyotypes with prevailing metacentric chromosomes, even in species belonging to different genera. Variability in diploid chromosome number was detected (2n = 18 to 2n = 60), and chromosome sizes were observed to be between 1.00 and 4.09 μm. Additionally, variation in the pattern of heterochromatin was observed mainly in relation to CMA+ bands, in which the number varied from 4 to 16 heterochromatic regions. Only one species, Vernonia scorpioides, presented positive DAPI bands, which were located in the terminal position in most of the chromosomes. The differences in the sizes and quantities of heterochromatic bands may be related to small structural rearrangements during karyotype evolution of the Vernonieae tribe.  相似文献   

8.
9.
The G-banded karyotypes of 20 species of the tribe Papionini are remarkably similar, and the amount of phylogenetic interpretation permitted is limited. The genera Mandrillus and Cercocebus may be linked by a derived chromosome 10. T. gelada may be linked to the macaques by chromosome 2. Chromosome 5, which differs in M. fascicularis, makes this species an unlikely ancestor of the Sulawesi (Celebes) macaques. An alternate hypothesis, which takes into consideration the possibility that ancestral populations may be polymorphic for these chromosome variants, suggests that different chromosome variants have become fixed in different lines. These chromosomes would therefore not reflect phylogenetic relations. In the Papionini the karyotype has not played a major role in diversification and speciation.  相似文献   

10.
This report describes the karyotypes of fourteen species of the tribe Chrysotoxini (Diptera, Syrphidae) with the single genus Chrysotoxum. The species are listed in the Table on p. 240. All have 2n=10 chromosomes, usually consisting of short apparently telocentric sex chromosomes plus two subtelocentric and two submetacentric pairs of autosomes.  相似文献   

11.
The pollen morphology of 120 samples of the tribe Orobancheae, representing four genera and 40 species of Cistanche, Diphelypaea, Orobanche and Phelipanche native to Turkey, has been studied by light and scanning electron microscopy. Pollen of the tribe Orobancheae is typically isopolar, radially asymmetrical, oblate spheroidal or prolate and belongs to one of the following basic pollen types: inaperturate, tricolpate and syncolpate. Also, pollen heteromorphism is widespread among pest species of Orobanche and Phelipanche. Pollen characters display considerable variation among genera and species, but some characters are significant at the levels of genera and sections. The results of the SEM study show that there are various exine ornamentation types in these genera. The obtained results support the division of the traditionally circumscribed genus Orobanche sensu lato into two genera, Phelipanche and Orobanche. The pollen morphological features are discussed on the basis of molecular phylogeny of the taxa.  相似文献   

12.
The somatic chromosomes and karyotypes of two Argentine populations of Capsicum chacoënse A. T. Hunz. have been studied, both of which have 2n=24. The karyotypes are symmetrical, being composed of 11 m paris + one st pair; two pairs of chromosomes are satellied: pairs 1 and 12 in one population and pairs 11 and 12 in the other one. A heteromorphic pair of satellited chromosomes in one individual suggests a spontaneous reciprocal translocation. Results are compared with previous reports for the species and genus. Data show an intraspecific karyotype variation.  相似文献   

13.
Heldreichia Boiss. is a monospecific genus mainly distributed in Anatolia and the Lebanon. Although morphological variation and infrageneric phylogenetic relationships were recently studied in detail, Heldreichia remained as one of the few orphan genera that have not yet been assigned to any tribe. In the current study, we used sequence data from the nuclear ITS and chloroplast ndhF regions of Heldreichia and representatives of main Brassicaceae lineages and tribes to determine its tribal affiliation. Bayesian-based phylogenetic analyses clearly show with high support that Heldreichia is a member of the recently expanded tribe Biscutelleae. Furthermore, we characterize the tribe Biscutelleae morphologically and provide a determination key for all its genera.  相似文献   

14.
15.
In many eutherian species, pairing and recombination of X and Y chromosomes are indispensable for normal meiotic progression and correct segregation of sex chromosomes. The rodent subfamily Arvicolinae provides an interesting exception. The majority of arvicoline species with asynaptic sex chromosomes belong to the genus Microtus sensu lato. However, some vole species of the genus Microtus and other genera display normal X-Y pairing in meiosis. These observations indicate that synaptic condition was typical for the common ancestor of all voles, but the gaps in taxonomic sampling makes impossible to identify a lineage or lineages, in which the asynapsis occurred. The methods of electron and fluorescent microscopy were used to study the synapsis of sex chromosomes in males of some additional species of the subfamily Arvicolinae. This extended taxonomic list allowed us to identify asynaptic species in every large lineage of the tribe Microtini. Apparently, the ability of sex chromosomes to pair and recombine in male meiosis was lost in arvicoline evolution for at least three times independently. Our results indirectly suggest the unnecessity of sex chromosome pairing in male meiosis of arvicoline rodents, and presence of alternate molecular mechanism of sex chromosome segregation in this large mammalian tribe.  相似文献   

16.
In this report the karyotypes of 54 species of the tribe Milesiini and of four species of the tribe Myoleptini are described in detail with illustrations and idiograms. These species belong in the genera Lejota, Myolepta, Blera, Calliprobola, Criorhina, Hadromyia, Milesia, Somula, Sphecomyia, Spilomyia, Syritta, Temnostoma, Tropidia and Xylota. Six species have 2n = 8 chromosomes, 35 have 2n = 10 (including Xylota nemorum which has about 20 extra microchromosomes in some specimens), 15 have 2n = 12, one has 2n = 14, and Somula decora has 2n = 10 large chromosomes plus about eight microchromosomes. The mean total complement length (TCL) for 347 complements analysed in these tribes was 53.7 but there is great variation between TCL's of complements analysed even from a single fly. Karyotypes of species of Myolepta in the Myoleptini resemble in certain respects those of species of Tropidia in the Milesiini. Our observations support Currran's transfer of Lejota cyanea to the Milesiini. The 2n = 12 karyotypes of species of Blera, Criorhina, Lejota, Milesia, and to a lesser extent Sphecomyia, have some features in common. Spilomyia species have rather distinct 2n = 10 karyotypes. Certain species in Calliprobola, Syritta and Hadromyia are karyologically similar to some species of the genus Xylota in which species studied fall into fairly distinct karyological groups. These observations provide clear evidence of the accumulation of karyotypic variations in the origin of species in these two tribes.  相似文献   

17.
Free amino acids and γ-glutamyl peptides have been examined in 22 species of Iridaceae. 3-(3′-Carboxyphenyl)alanine and 3′-carboxyphenylglycine, previously known from the tribes Irideae and Tigridideae in the subfamily Iridodeae have been identified also in the tribe Mariceae of Iridoideae and the genera Bobartia, Orthrosanthus and Libertia of the subfamily Sisyrinchioideae. γ-Glutamyl peptides, previously known from the tribe Irideae, have been found also in the tribe Mariceae, both tribes being from subfamily Iridoideae. γ-Glutamyl-S-methylcysteine, γ-glutamylmethionine and the corresponding sulphoxides are the dominating γ-glutamyl peptides in the genera Dietes, Gynandriris, Moraea (tribe Irideae), Neomarica and Trimezia (tribe Mariceae), whereas γ-glutamyl peptides with non-sulphur amino acids are predominant in genera Ferraria, Hermodactylus, Homeria, Iris, Iridodyctyum and Xiphium (tribe Irideae). Dietes robisoniana, endemic to Lord Howe Island, has the same technical characters as other Dietes species from Southern Africa. The results are discussed in relation to botanical classification of and within the subfamilies Iridoideae and Sisyrinchoideae.  相似文献   

18.
We determined the karyotypes of nine species of Lessingianthus, eight of which are here analyzed for the first time. The results include the first chromosome count for L. plantaginoides, which is tetraploid with 2n = 64. All species showed a high proportion of metacentric chromosomes combined with a lower proportion of submetacentric pairs. Only L. coriaceus had a subtelocentric chromosome pair. B chromosomes were observed in L. coriaceus and L. varroniifolius, which were subtelocentric. Differences among the karyotypes of the studied species were small, suggesting that karyotype diversity in the genus evolved by small changes in the structure of chromosomes. Karyotype features appear useful to distinguish Lessingianthus from the closely related genera Chrysolaena and Lepidaploa.  相似文献   

19.
The karyotypes of 24 species of the tribe Pipisini (Diptera: Syrphidae) are described and illustrated. Nearly all the species of Neocnemodon, Pipiza and Pipizella have 2n=8 chromosomes consisting of a short telocentric XY pair and three metacentric pairs increasing in relative length from long to very long. Pair II chromosomes in several Pipiza species have high metacentric to low submetacentric arm ratios. One Parapenium species is tentatively reported as having five pairs and another five or six pairs. The karyological evidence favours placing the tribe Pipizini in the subfamily Syrphinae rather than in the subfamily Milesiinae.  相似文献   

20.
The tribe Colpopterini Gnezdilov, 2003 is revised, upgraded to the subfamily Colpopterinae, stat. n., and transferred from the family Issidae Spinola to Nogodinidae Melichar. The tribe Colpopterini is recorded from the Afrotropical Region for the first time—Bumerangum deckerti gen. et sp. n. is described from Southern Africa. The tribe Colpopterini s. str. comprises 6 genera: Bumerangum gen. n., Caudibeccus Gnezdilov et O’Brien, 2008, Colpoptera Burmeister, 1835, Jamaha Gnezdilov et O’Brien, 2008, Neocolpoptera Dozier, 1931, and Ugoa Fennah, 1945. The genera Cheiloceps Uhler, 1895, Tempsa Stål, 1866, Eupilis Walker, 1857, and Gabaloeca Walker, 1870 are transferred to the tribe Issini Spinola of the family Issidae. Issus longulus Lethierry, 1890 is transferred to the genus Colpoptera Burmeister. A key to the genera and a list of the species of the tribe Colpopterini are given. Morphological data confirming independent evolution of similar ovipositor types in the families Issidae and Nogodinidae are provided. The term “styletization” is suggested for describing the transformation of the ovipositor from a rounded to an elongate type.  相似文献   

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