• 환경생물
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• 제40권3호
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• pp.301-306
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• 2022

The vegetative and reproductive morphology of some parasitic Janczewskia Solms-Laubach species including the type species was examined based on specimens collected from various localities around the world. In J. gardneri Setchell et Guernsey on Osmundea spectabilis (Postels et Ruprecht) Nam from California, secondary pit connections are not found between epidermal cells and vegetative axial cells have two pericentral cells. As its host, J. gardneri also has a typical filament type male structure in an apical urn-shaped pit of branches rather than the trichoblast type in other species including the type J. verruciformis Solms-Laubach and tetrasporangial origin of epidermal cells rather than pericentral cells. These significant differences between the species suggest that J. gardneri should be separated from the genus Janczewskia. Based on this morphological data, the section Heterojanczewskia Setchell including J. gardneri, together with an emendation of the generic delineation of Janczewskia, is elevated to the genus level. Relevant nomenclatural changes for some Janczewskia species are also included here.

• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.25-31
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• 1999

Developmental morphology of the red alga, Osmundea crispa (Hollenberg) Nam from California was studied on the basis of liquid-preserved and herbarium specimens. Vegetative axial segment of the species produces two pericentral cells and one trichoblast. Spermatangial filaments (branches) are derived from apical and epidermal cells in pocket-shaped apical pit with an ostiole-like upper opening. Procarp-bearing segment of female trichoblast produces five pericentral cells, of which the fifth functions as supporting cell of carpogonial branch. Tetrasporangial production occurs in random epidermal cells in apical pit of branchlets, and two presporangial cover cells show parallel arrangement to stichidial axis. As this vegetative and reproductive development is included in the generic delineation of Osmundea Stackhouse, O. crispa among the known Osmundea species is characterized by habit forming compact cushion-like clump with angular to terete thallus. It is also distinguished from O. hybrida (AP. de Candolle) Nam without the compressed thallus by the number of pericentral cells in procarp-bearing segment and shape of spermatangial pit. Taxonomic implication of the shape of spermatangial pit is also included.