Chromosome numbers in the proteaceae

1963 ◽  
Vol 11 (1) ◽  
pp. 1 ◽  
Author(s):  
HP Ramsay
Keyword(s):  
Chromosome Number ◽  
South African ◽  
Chromosome Numbers ◽  
The Family ◽  
The One

Chromosome numbers have been determined for 19 genera and 53 species of Proteaceae in Australia. The chromosomes are small in all genera except Persoonia n = 7, Placospermum n = 7 (Johnson and Briggs 1963) and Bellendena n = 5 (Venkata Rao 1957), which have chromosomes comparable in size with those in the Liliaceae and Ranunculaceae. In other Australian genera chromosome numbers range from n = 14 (Cenarrhenes, Macadamia, Xylornelum, Lambertia, Banksia, Dryandra), n = 13 (Isopogon, Petrophile, Stirlingia, Adenanthos), n = 11 (Conospermum, Telopea, Lomatia, Stenocarpus) to n = 10 (Symphionema, Grevillea, Hakea). There are no genera counted so far in Australia with n = 12, a number common to many South African Proteaceae. Only one example of intrageneric polyploidy in the family is reported, for Persoonia toru A. Cunn. n = 14 by Hair and Beuzenberg (1959), while Venkata Rao (1957) discovered one example of intrageneric difference in number in two species of Orites with n = 14, 15, but in all other members of the family investigated, the chromosome numbers are constant for all species of the one genus, indeed for all the genera in certain tribes, e.g. Banksieae. Cytological evolution and distribution of the family have been discussed and a scheme representing possible chromosome number relationships drawn up.

scholarly journals Check-list of chromosome numbers of the family Hygromiidae (Gastropoda: Stylommatophora) with new data on Circassina frutis

2021 ◽  
Vol 64 (2) ◽  
pp. 7-20
Author(s):  
Nana Bakhtadze ◽  
Nino Gabroshvili ◽  
Levan Mumladze ◽  
Nino Gabroshvili
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Land Snail ◽  
Haploid Number ◽  
Check List ◽  
Fundamental Number ◽  
Diploid Complement ◽  
The Family ◽  
Karyotype Formula ◽  
First Time

Chromosome number data on the Hygromiidae (Gastropoda: Stylommatophora) are summarized and reviewed briefly in the context of the phylogeny of the family. In hygromiids, the haploid chromosome numbers range from 21 to 26. It is supposed that n = 21 is the ancestral chromosome number in the family. The modal haploid number for Hygromiidae is 23. Description of karyotype in terms of chromosome number and morphology of hygromiid land snail Circassina frutis is provided for the first time. The diploid chromosome number of this species is 2n = 46. The karyotype is symmetric and consists of 21 pairs of metacentric and 2 pairs of submetacentric chromosomes. The karyotype formula is as follows: 2n = 42m + 4sm (n = 21m + 2sm). The fundamental number (FN) is 92. Chromosomes range in length from 2.53 μm for the smallest pair to 6.00 μm for the largest pair. The total length of chromosomes in diploid complement (TCL) is 170.40 ± 3.22 μm.

scholarly journals Karyotype description and comparative analysis in Ringed Kingfisher and Green Kingfisher (Coraciiformes, Alcedinidae)

2018 ◽  
Vol 12 (2) ◽  
pp. 163-170
Author(s):  
Tiago Marafiga Degrandi ◽  
Jean Carlo Pedroso de Oliveira ◽  
Amanda de Araújo Soares ◽  
Mario Angel Ledesma ◽  
Iris Hass ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Chromosome Number ◽  
Chromosome Numbers ◽  
Diploid Number ◽  
Chromosomal Rearrangements ◽  
The Family ◽  
Cytogenetic Studies ◽  
Karyotype Structure ◽  
Chromosome Fusions ◽  
Size And Morphology

Kingfishers comprise about 115 species of the family Alcedinidae, and are an interesting group for cytogenetic studies, for they are among birds with most heterogeneous karyotypes. However, cytogenetics knowledge in Kingfishers is extremely limited. Thus, the aim of this study was to describe the karyotype structure of the Ringed Kingfisher (Megaceryletorquata Linnaeus, 1766) and Green Kingfisher (Chloroceryleamericana Gmelin, 1788) and also compare them with related species in order to identify chromosomal rearrangements. The Ringed Kingfisher presented 2n = 84 and the Green Kingfisher had 2n = 94. The increase of the chromosome number in the Green Kingfisher possibly originated by centric fissions in macrochromosomes. In addition, karyotype comparisons in Alcedinidae show a heterogeneity in the size and morphology of macrochromosomes, and chromosome numbers ranging from 2n = 76 to 132. Thus, it is possible chromosomal fissions in macrochromosomes resulted in the increase of the diploid number, whereas chromosome fusions have originated the karyotypes with low diploid number.

Chromosome Number Variation in the Myrtaceae and Its Taxonomic Implications

1979 ◽  
Vol 27 (5) ◽  
pp. 547 ◽  
Author(s):  
BL Rye
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Evolutionary Potential ◽  
The Family ◽  
Number Variation ◽  
Taxonomic Implications ◽  
Chromosome Number Variation ◽  
Australian Flora ◽  
Base Chromosome Number ◽  
Western Australian

New chromosome number determinations are reported for some 150 Western Australian species of the Myrtaceae. These include the lowest number (n = 5) so far recorded in the family and several newly recorded descending dysploid series. Dysploid chromosome numbers are far less common than the base chromosome number of n = 11 but parallel dysploid series have occurred in many groups and some have played a role in the origin of genera. Polyploidy has been successful at the intraspecific and interspecific levels but is of limited evolutionary potential. The cytoevolutionary trends in the Myrtaceae are examined in relation to taxonomic problems within the family and in relation to cytoevolution in the woody Australian flora as a whole. Smith- White's suggestion that a more natural generic classification in the Chamelauciinae could be obtained by grouping species with the same base chromosome numbers is found to be untenable.

Phylogenetics and chromosomal evolution in the Poaceae (grasses)

2004 ◽  
Vol 52 (1) ◽  
pp. 13 ◽  
Author(s):  
Khidir W. Hilu
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Chromosome Doubling ◽  
Chromosomal Evolution ◽  
Basic Chromosome Number ◽  
Basic Chromosome ◽  
Wide Range ◽  
The Family

The wide range in basic chromosome number (x = 2–18) and prevalence of polyploidy and hybridisation have resulted in contrasting views on chromosomal evolution in Poaceae. This study uses information on grass chromosome number and a consensus phylogeny to determine patterns of chromosomal evolution in the family. A chromosomal parsimony hypothesis is proposed that underscores (1) the evolution of the Joinvilleaceae/Ecdeiocoleaceae/Poaceae lineage from Restionaceae ancestors with x = 9, (2) aneuploid origin of x�=�11 in Ecdeiocoleaceae and Poaceae (Streptochaeta, Anomochlooideae), (3) reduction to x = 9, followed by chromosome doubling within Anomochlooideae to generate the x = 18 in Anomochloa, and (4) aneuploid increase from the ancestral x = 11 to x = 12 in Pharoideae and Puelioideae, and further diversification in remaining taxa (Fig. 3b). Higher basic chromosome numbers are maintained in basal taxa of all grass subfamilies, whereas smaller numbers are found in terminal species. This finding refutes the 'secondary polyploidy hypothesis', but partially supports the 'reduction hypothesis' previously proposed for chromosomal evolution in the Poaceae.

The annual species of stinging nettle (Hesperocnide and Urtica) in North America

1976 ◽  
Vol 54 (3-4) ◽  
pp. 374-383 ◽  
Author(s):  
D. W. Woodland ◽  
I.J. Bassett ◽  
C. W. Crompton
Keyword(s):  
North America ◽  
Chromosome Number ◽  
Chromosome Numbers ◽  
Annual Species ◽  
Chromosome Counts ◽  
Stinging Nettle ◽  
The One ◽  
North America North

Descriptions (including those of pollen), distributional data, and chromosome counts are given for one species of Hesperocnide and three annual species of Urtica (stinging nettles) in North America north of Mexico: Hesperocnide tenella, Urtica chamaedryoides, U. gracilenta, and U. urens. Hesperocnide tenella has a chromosome number of 2n = 24 while all three Urtica spp. have the same chromosome number of 2n = 26. All reported chromosome numbers are new except the one for U. urens. A key which separates the taxa that are studied is provided and synonyms that are applied to the species are discussed.

Variation in chromosome number in the Manuleae (Scrophulariaceae) and its cytotaxonomic implications

1993 ◽  
Vol 50 (3) ◽  
pp. 365-379
Author(s):  
K. Jong
Keyword(s):  
Chromosome Number ◽  
South African ◽  
Chromosome Numbers ◽  
Somatic Number ◽  
Basic Numbers

Chromosome numbers for 11 genera and 36 species in the predominantly South African tribe Manuleae (Scrophulariaceae) are presented, the majority being first reports. The basic numbers of the genera form a dysploid series, x = 6, 7, 8, 9. The somatic number of most of the species is diploid, ranging from 2n = 12 to 2n = 18; that of Jamesbrittenia, 2n = 24, is probably of polyploid derivation. The highest somatic number encountered in this survey is that in Camptoloma lyperiiflorum, with 2n = c.56, which, taken in conjunction with a published count of 2n = 28 for another species of Camptoloma, is octoploid based on x = 7. This is the only example, so far, of intrageneric polyploidy in the Manuleae. The somatic number in certain genera appears to be constant over some subgeneric divisions (e.g. Jamesbrittenia, 2n = 24), but variable in others (e.g. Sutera, 2n = 12, 14). The variation in chromosome number observed in this study parallels and corroborates the redefinition of generic boundaries proposed by O. M. Hilliard. One species of Selago (in the tribe Selagineae) was also included in this survey for cytological comparison with Tetraselago (Manuleae).

scholarly journals Genome size, chromosome number determination, and analysis of the repetitive elements in Cissus quadrangularis

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e8201
Author(s):  
Duncan Kiragu Gichuki ◽  
Lu Ma ◽  
Zhenfei Zhu ◽  
Chang Du ◽  
Qingyun Li ◽  
...  
Keyword(s):  
Chromosome Number ◽  
Genome Size ◽  
Chromosome Numbers ◽  
Arid Regions ◽  
Repetitive Elements ◽  
Repeat Elements ◽  
Cissus Quadrangularis ◽  
Wide Range ◽  
The Family ◽  
Animal Medicine

Cissus quadrangularis (Vitaceae) is a perennial climber endemic to Africa and is characterized by succulent angular stems. The plant grows in arid and semi-arid regions of Africa especially in the African savanna. The stem of C. quadrangularis has a wide range of applications in both human and animal medicine, but there is limited cytogenetic information available for this species. In this study, the chromosome number, genome size, and genome composition for C. quadrangularis were determined. Flow cytometry results indicated that the genome size of C. quadrangularis is approximately 2C = 1.410 pg. Fluorescence microscopy combined with DAPI stain showed the chromosome numbers to be 2n = 48. It is likely that C. quadrangularis has a tetraploid genome after considering the basic chromosome numbers in Cissus genus (n = 10, 11, or 12). A combination of low-throughput genome sequencing and bioinformatics analysis allowed identification and quantification of repetitive elements that make up about 52% of the C. quadrangularis genome, which was dominated by LTR-retrotransposons. Two LTR superfamilies were identified as Copia and Gypsy, with 24% and 15% of the annotated clusters, respectively. The comparison of repeat elements for C. quadrangularis, Vitis vinifera, and four other selected members in the Cissus genus revealed a high diversity in the repetitive element components, which could suggest recent amplification events in the Cissus genus. Our data provides a platform for further studies on the phylogeny and karyotype evolution in this genus and in the family Vitaceae.

scholarly journals Chromosomal analysis of Astyanax fasciatus (PISCES, CHARACIDAE) from the Araguari river, Uberlândia, MG, Brazil

2006 ◽  
Vol 66 (1a) ◽  
pp. 161-165 ◽  
Author(s):  
A. R. Torres-Mariano ◽  
S. Morelli
Keyword(s):  
Chromosome Number ◽  
Silver Nitrate ◽  
Chromosome Numbers ◽  
Chromosomal Analysis ◽  
Diploid Chromosome Number ◽  
Nucleolar Organizing Regions ◽  
Astyanax Fasciatus ◽  
The Family ◽  
Silver Nitrate Staining ◽  
Parana Basin

The genus Astyanax is one of the most numerous of the family Characidae, comprising a large number of similar-shaped species, but displaying innumerable karyotypic variations in its chromosome number and/or structure. The literature describes A. fasciatus populations with diploid chromosome numbers varying from 2n = 45 to 2n = 48. In this study, A. fasciatus specimens captured in the Araguari River (Alto Paraná basin) were cytogenetically characterized, revealing a diploid chromosome number of 2n = 46. The nucleolar organizing regions (NORs), detected with silver nitrate staining, showed a multiple system with two pairs of marked chromosomes. These findings are congruent with those of other studies involving populations of the same species.

scholarly journals Malpighiaceae: correlations between habit, fruit type and basic chromosome number

2003 ◽  
Vol 17 (2) ◽  
pp. 171-178 ◽  
Author(s):  
Ricardo A. Lombello ◽  
Eliana R. Forni-Martins
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Basic Number ◽  
Basic Chromosome Number ◽  
Basic Chromosome ◽  
Monophyletic Origin ◽  
The Family ◽  
Number Variation ◽  
Family Based ◽  
The Relationship

The family Malpighiaceae presents species with different habits, fruit types and cytological characters. Climbers are considered the most derived habit, followed, respectively, by the shrubby and arboreal ones. The present study examines the relationship between basic chromosome numbers and the derivation of climbing habit and fruit types in Malpighiaceae. A comparison of all the chromosome number reports for Malpighiaceae showed a predominance of chromosome numbers based on x=5 or 10 in the genera of sub-family Malpighioideae, mainly represented by climbers with winged fruits, whereas non-climbing species with non-winged fruits, which predominate in sub-family Byrsonimoideae, had counts based on x=6, which is considered the less derived basic number for the family. Based on such data, confirmed by statistic assays, and on the monophyletic origin of this family, we admit the hypothesis that morphological derivation of habit and fruit is correlated with chromosome basic number variation in the family Malpighiaceae.

Chromosome numbers from pollen in some North American Impatiens (Balsaminaceae)

1974 ◽  
Vol 52 (12) ◽  
pp. 2637-2639 ◽  
Author(s):  
C. C. Chinnappa ◽  
L. S. Gill
Keyword(s):  
North America ◽  
Chromosome Number ◽  
North American ◽  
Chromosome Numbers ◽  
Herbarium Specimens ◽  
Chromosome Counts ◽  
Present Survey ◽  
The One ◽  
Basic Numbers

Chromosome counts for eight species of Impatiens from North American populations have been determined from herbarium specimens. The chromosome number n = 10 for I. ecalcarata Blank, is a new report. It is apparent from the present survey that there are at least three basic numbers (n = 7, 10, and 13) represented in North America as opposed to the one (n = 10) suggested by the earlier workers.

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