Myosotis
The genus Myosotis comprises approximately 80 species distributed nearly throughout all regions of the World, predominantly in Eurasia, New Zealand and New Guinea. The taxonomic complexity of the genus Myosotis and the great differences among authors with regard to their concept of the species or other taxa in this genus, results from wide morphological and karyological variability combined with the absence of reliable morphological traits that could be diagnostic for the individual taxa. The considerable variation (both cytological and phenotypic) depends on a number of factors. The most important ones can be summarized as follows: polyploidy, a relatively complicated breeding system (combination of sexual and asexual reproduction modes), hybridization and a high level of phenotypic plasticity. At the present, two groups are studied more profoundly: the Myosotis palustris and the Myosotis alpestris groups. Data based both on common biosystematic (morphological analysis including multivariate biometrical studies, nomenclatural, biogeographical and karyological examination) and molecular methods (analyses of cp DNA, ITS regions of nr DNA) have been applied to fully document single taxa of these groups, the pattern of biotic diversity and to estimate evolutionary and speciation pathways within these series.
Projects
- The phenomenon of endemism in the Krkonoše (the Giant Mts.), its origin, development and recent change. (GA CAS, 1991-1993, particular project on Myosotis alpestris).
- Between-population differentiation in serpentine island-like areas: Variation of higher plants in a severe environment. (GA CR, 1994-96, particular project on Myosotis stenophylla).
- Origin and current diversification in clonal polyploids of the Myosotis palustris group: phylogenetic evidence from molecular and biosystematic data. (GA CAS, 1995-1998).
- A monograph of Myosotis ser. Palustres (Boraginaceae) - A powerful tool for revealing and maintenance of biotic diversity within group. (GA CR, 1999-2001).
- Phylogeny and recent differentiation in the European alpine/lowland populations of the polyploid complex of Myosotis alpestris (Boraginaceae). (GA CAS, 2003-2006)
Literature references
Štěpánková J. et Markova L. M. (1991): A note on distribution of Myosotis orbelica. - Preslia, 63:329-331.
Štěpánková J. (1993): Ploidy variation in the group of Myosotis palustris and M. laxa in the Czech Republic and Slovakia. - Folia Geobot.Phytotax., 28:113 - 128.
Štěpánková J. (1993): Myosotis margaritae - A new species from Bulgaria. - Folia Geobot. Phytotax., 28:279-288.
Štěpánková J. (1993): Report on Myosotis L. - In: Kamari G., Felber F. et Gabari F. [ed.]: Mediterranean chromosome number reports, 3, Flora Mediterranea, 3:323-373.
Štěpánková J. (1993): Remarks on the karyogeography of the Myosotis alpestris in Europe. - Preslia 65:325-334.
Štěpánková J. (1994): Myosotis michaelae - a new species of Myosotis ser. Palustres (Boraginaceae). - Folia Geobot. Phytotax. 29:375-384.
Štěpánková J. (1994): Myosotis sicula new to Hungary. - Preslia 66:255-259.
Štěpánková J. (1994): Myosotis margaritae - a new species for Greece, Romania and Serbia. - Preslia 66:261-264.
Štěpánková J. (1996): Karyological variation in the group Myosotis alpestris (Boraginaceae). - Folia Geobot. Phytotax. 31: 251-262.
Štorchová H. and Štěpánková J.(1996): RAPD in the genus Myosotis - optimization of the PCR reaction. - Chemické listy 90:703-704.
Štěpánková J. (1997): Karyological differentiation and evolution in the Myosotis palustris group. Spring symposium on Plant Cytogenetics, p. 63. Cieszyn. (Abstract)
Štěpánková J. (2000): 16. Myosotis L. - pomněnka. - In: Slavík B. (ed.), Květena České republiky 6, p. 216-234, Academia, Praha.
Štěpánková J. (2001): Nonadaptive hypothesis of allopatric cytotype distribution in Myosotis lamottiana (Boraginaceae). – Folia Geobot. 36:147-161.
Štěpánková J. (2006). Karyotaxonomy of Myosotis alpestris group. - Preslia 78: 345–352.
