Cytological studies of Australian mosses

Abstract

The cytological features of 84 species from 56 genera and 33 families from almost 200 collections of Australian mosses are described. A wide range of chromosome numbers is recorded: n = 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 20, 21, 22, 30, 48, and 52 ± 2. Variation in numbers occurred in both genera and species, and intraspecific polyploidy for 10 species and intraspecific aneuploidy for four species are reported. The investigations have shown that the same mechanisms of speciation, range of chromosome numbers, degrees of polyploidy and intraspecific variations occur here as in other parts of the world. The studies have contributed information on 62 species, 18 genera and five families not previously recorded and form the first survey of the cytology of Australian mosses.

Australian mosses - new chromosome numbers and a compilation of chromosome data

“…The various cytological studies have shown that in the Australasian region the numbers and morphology of the chromosomes examined are comparable with those obtained in other parts of the world (Ramsay 1969(Ramsay , 1974(Ramsay , 1983bFritsch 1991). Some unique data for Australia and New Zealand include the low chromosome numbers n=4, 5 for Hypnodendraceae (Ramsay 1974(Ramsay , 1987(Ramsay , 1988 while the possible presence of sex chromosomes in Macromitrium, as indicated by dimorphic bivalents, anisospory and dwarfism of males, has been discussed (Ramsay 1966a(Ramsay , 1979(Ramsay , 1983cRamsay & Berrie 1982;Smith & Ramsay 1982;Ramsay & Vitt 1986). In addition, the presence of 'm' chromosomes in Macromitrium (Ramsay 1966a(Ramsay , 1974(Ramsay , 1983c and various other mosses, e.g.…”

“…Techniques follow those of Ramsay (1974Ramsay ( , 1982Ramsay ( , 1983c, i.e. fixing and staining in aceto-orcein or aceto-carmine, with preservation of slides by freezing with carbon dioxide and mounting in euparal.…”

“…Intraspecific polyploidy is reported in a number of mosses (e.g. Hypopterygium tamarisci as H. rotulatum in Ramsay 1967b) while chromosome numbers, resulting from polyploidy in various colonising species, are particularly high in the Bryaceae, Pottiaceae and Funariaceae (Ramsay 1974(Ramsay , 1983c increasing genetic diversity and possibly accounting for their success in stressful environments.…”

“…Some studies have been carried out separately for New Zealand mosses but most Australian results have been published by the author (Ramsay 1964(Ramsay , 1966b(Ramsay , 1967a(Ramsay , 1967b(Ramsay , 1973(Ramsay , 1974(Ramsay , 1977(Ramsay , 1979(Ramsay , 1982(Ramsay , 1983a(Ramsay , 1983b(Ramsay , 1983c(Ramsay , 1985(Ramsay , 1987(Ramsay , 1988(Ramsay , 1992(Ramsay , 1993(Ramsay , 1997(Ramsay , 2006(Ramsay , 2008(Ramsay , 2009, or in collaboration with others, e.g. Ramsay & Lewinsky (1984), Ramsay & Vitt (1986), Ramsay & Bergstrom (1995), , Ramsay & Spence (1996), Ramsay et al (2002).…”

“…Some unique data for Australia and New Zealand include the low chromosome numbers n=4, 5 for Hypnodendraceae (Ramsay 1974(Ramsay , 1987(Ramsay , 1988 while the possible presence of sex chromosomes in Macromitrium, as indicated by dimorphic bivalents, anisospory and dwarfism of males, has been discussed (Ramsay 1966a(Ramsay , 1979(Ramsay , 1983cRamsay & Berrie 1982;Smith & Ramsay 1982;Ramsay & Vitt 1986). In addition, the presence of 'm' chromosomes in Macromitrium (Ramsay 1966a(Ramsay , 1974(Ramsay , 1983c and various other mosses, e.g. Dicranoloma by Ramsay (1987Ramsay ( , 1988 in Australia, and for other mosses in Europe, North America and Japan (summarised in Anderson & Bryan 1987) and demonstrated in Plagiomnium affine by Klos et al (2001), have been noted.…”