Biodiversity, biogeography and conservation of diatoms

摘要: Recent morphometric and breeding studies of diatoms show that the present species classification is too coarse hides significant diversity. Many are subdivided into phenodemes, which often differ in cell size, shape, stria density pattern, but may also have different ultrastructural features. In raphid these can include form raphe endings, details pore occlusions, structure girdle, while chloroplast vary. The phenodemes be sympatric or allopatric. Sellaphora pupula other species, reproductively isolated. It recommended such demes recognized as separate species; total number diatom worldwide thus at least 2 × 105. Use a fine-grained reveals many endemics, some restricted to single lake catchment, others wider areas. Environmental impact assessments conservation strategies must begin take account endemism rarity among microscopic algae protists.