Mitotic analysis of the North American white sturgeon, <i>Acipenser</i> <i>transmontanus</i> Richardson (Pisces, Acipenseridae), a fish with a very high chromosome number

The average chromosome number of the North American white sturgeon, Acipenser transmontanus Richardson, was found to be 271 ± 2.5 (ranging from 265 to 276). This number is significantly higher than previous estimates for this species. A representative karyotype was found to consist of 132 meta- and submeta-centric chromosomes, 44 acrocentric chromosomes, and 98 microchromosomes. An improved C-banding technique revealed variation (2-7) between animals in the number of entirely heterochromatic metacentric chromosomes. These heterochromatic chromosomes may represent supernumerary chromosomes. There was no cytogenetic evidence of a heteromorphic sex chromosome pair or any sex-related chromosomal polymorphism in either sex of this species.Key words: C-banding, fish, karyotype, supernumerary chromosomes, white sturgeon.

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STOLAINE CASSIDINES (COLEOPTERA, CHRYSOMELIDAE) WITH Xyp SEX CHROMOSOMES AND A DERIVATIVE SYSTEM XpneoXneoYp

Canadian Journal of Genetics and Cytology ◽

10.1139/g74-045 ◽

1974 ◽

Vol 16 (2) ◽

pp. 433-440 ◽

Cited By ~ 10

Author(s):

E. S. de Vaio ◽

A. Postiglioni

Keyword(s):

Chromosome Number ◽

Sex Chromosomes ◽

High Chromosome Number ◽

Multiple Sex Chromosomes ◽

Autosome Translocation ◽

Derivative System ◽

Very High

Three species of Cassidines were cytologically studied. Chelymorpha indigesta and C. variabilis, with 10II + Xyp, have a relatively primitive Coleopteran karyotype and the sex chromosomes form a parachute-like bivalent. Botanochara angulata, belonging to the same tribe, Stolaini, presents an exceptional karyotype with a very high chromosome number (2n = 51 ♀) and multiple sex chromosomes XpneoXneoYp. This system has derived from the Xyp by a yp-to-autosome translocation.

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Taxonomy of the Carex flava complex (Cyperaceae) in North America and northern Eurasia. II. Taxonomic treatment

Canadian Journal of Botany ◽

10.1139/b89-138 ◽

1989 ◽

Vol 67 (4) ◽

pp. 1048-1065 ◽

Cited By ~ 17

Author(s):

William J. Crins ◽

Peter W. Ball

Keyword(s):

North America ◽

Chromosome Number ◽

North American ◽

Northern Eurasia ◽

Distribution Maps ◽

Taxonomic Treatment ◽

The North ◽

Infraspecific Taxa ◽

History Of ◽

Inflorescence Structure

The taxonomy of the Carex flava complex (section Ceratocystis) in North America and northern Eurasia is revised. Three species are recognized in this complex (C. flava L., C. cryptolepis Mack., and C. viridula Michx.). Carex viridula contains six infraspecific taxa, which are differentiated on the basis of differences in inflorescence structure, degree of perigynium curvature, leaf and bract morphology, chromosome number, and ecological preference. Three nomenclatural changes are required: C. viridula ssp. brachyrrhyncha (Čelak.) B. Schmid var. elatior (Schlecht.) Crins, comb.nov.; C. viridula ssp. brachyrrhyncha var. nevadensis (Boiss. & Reuter) Crins, comb.nov.; C. viridula ssp. brachyrrhyncha var. saxilittoralis (Robertson) Crins, comb, et stat.nov. This classification reflects the results of morphological, ecological, and cytological studies, and is also consistent with the hypothesized phylogenetic history of the section as a whole. A key is provided for all of the North American and northern Eurasian members of section Ceratocystis. Descriptions and distribution maps for members of the C. flava complex are also provided.

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BASIC CHROMOSOME NUMBER, CYANOGENETIC GLUCOSIDE VARIATION, AND GEOGRAPHIC DISTRIBUTION OF LOTUS SPECIES

Canadian Journal of Botany ◽

10.1139/b67-070 ◽

1967 ◽

Vol 45 (5) ◽

pp. 639-647 ◽

Cited By ~ 32

Author(s):

William F. Grant ◽

B. S. Sidhu

Keyword(s):

Chromosome Number ◽

Geographic Distribution ◽

North American ◽

New World ◽

Basic Chromosome Number ◽

North American Species ◽

Hydrocyanic Acid ◽

Basic Chromosome ◽

Fresh Leaf ◽

The North

Leaves of 51 species and three varieties of Lotus (Leguminosae) were assessed quantitatively for hydrocyanic acid (HCN) reaction intensity and the data correlated with basic chromosome number and geographic distribution. The presence of HCN was determined from 0.05 grams of fresh leaf samples by the picric acid – filter paper technique. A gradation of 10 different color reactions (−), (±), and (+1 to +8) was used to compare the HCN reaction for each species. On the basis of potassium cyanide equivalents, each gram of fresh leaf material was estimated to contain an amount of HCN which varied between the different plants and accessions from 0.5 mg to 750 mg. Most of the Old World species were positive for HCN, whereas the reverse was true for the North American species. This would favor the previous separation of the North American species into a separate genus Hosackia. All of the n = 7 species have a greater concentration of HCN than the n = 6 species in both the Old and New World. None of the n = 6 species in the New World reacted positively. Therefore, there was a reduction of HCN with evolutionary development. Two colchicine-induced tetraploids (4x = 24, 28) gave a lower HCN reaction than their diploid counterparts. Leaves of L. siliquosus (n = 7) reacted negatively to the HCN test; however, the cotyledons gave a highly positive reaction supporting the retention of the generic name Tetragonolobus (T. siliquosus (L.) Roth.) for this species. Chromosome number determinations are reported for the first time for L. holosericeus Webb and Berth. (2n = 14), L. mascaensis Buchard (2n = 28), L. nevadensis Greene (2n = 14), L. helleri Britton (2n = 14), and L. oblongifolius var. nevadensis (Gray) Munz (2n = 14).

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TAXONOMICAL VALUE OF ALISMA TRIVIALE PURSH AND ALISMA SUBCORDATUM RAFIN

Canadian Journal of Botany ◽

10.1139/b63-085 ◽

1963 ◽

Vol 41 (7) ◽

pp. 1011-1013 ◽

Cited By ~ 2

Author(s):

Eugenia Pogan

Keyword(s):

Chromosome Number ◽

North American ◽

Morphological Characters ◽

The North

Detailed morphological and karyological studies have revealed that the North American taxa of the Alisma plantago-aquatica complex are most appropriately classified as the two species, A. subcordatum Rafin. (2n = 14), and A. triviale Pursh (2n = 28). The morphological characters separating these species and distinguishing them from the European diploid, A. plantago-aquatica L., s. str., are given, and also the chromosome number of American material of A. gram-ineum Gmel. (2n = 14).

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ISIS and studbooks, very high census correlation for the North American zoo population: A reply to Earnhardt, Thompson, and Willis

Zoo Biology ◽

10.1002/zoo.1430140603 ◽

1995 ◽

Vol 14 (6) ◽

pp. 509-517 ◽

Cited By ~ 7

Author(s):

Nathan R. Flesness ◽

David R. Lukens ◽

Stephen B. Porter ◽

Crispen R. Wilson ◽

Larry V. Grahn

Keyword(s):

North American ◽

The North ◽

Very High

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CYTOTAXONOMY OF EUPHORBIA ESULA IN CANADA AND ITS HYBRID WITH EUPHORBIA CYPARISSIAS

Canadian Journal of Botany ◽

10.1139/b58-048 ◽

1958 ◽

Vol 36 (4) ◽

pp. 547-559 ◽

Cited By ~ 10

Author(s):

R. J. Moore

Keyword(s):

Chromosome Number ◽

North American ◽

Leafy Spurge ◽

Euphorbia Esula ◽

The North ◽

Artificial Hybrid ◽

Euphorbia Cyparissias

In 14 collections of leafy spurge from Ontario and Saskatchewan the chromosome number is 2n = 60. The problem of the correct botanical name of this plant is reviewed; all the North American collections seen are classed as E. esula L. sensu lato. The morphology and cytology of an artificial hybrid, E. cyparissias × E. esula, is described; its chromosome number is 2n = 50 and meiosis is irregular. The name E. × figertii Dörfler usually applied to this hybrid is rejected in favor of the prior name E. × pseudo-esula Schur.

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