An ecophysiological study of the lycophyte Selaginella kraussiana

Selaginella kraussiana, native to Sub-Saharan Africa and Macaronesia, has become naturalized in many other regions worldwide, including parts of Europe, North America, South America, Australia, and New Zealand. As a widely studied lycophyte species in the family Selaginellaceae, it is representative of this class of spore-bearing, vascular plants that form a significant part of forest understory flora and other mesophytic environments. Consequently, additional research on its physiological ecology is warranted, particularly photosynthesis and dark respiration, which are important for documenting its role in ecosystem carbon balance. The objective of this study was to provide data on the photosynthesis rate, respiration rate, and leaf fluorescence properties for laboratory-cultivated S. kraussiana toward establishing a stronger base of evidence for its role in ecosystem dynamics. The mean maximum photosynthesis rate was measured as follows: 2.25 ± 0.12 µmol m² s?¹ per leaf area, 401.70 ± 43.38 nmol g?¹ min?¹ per leaf fresh weight, and 3,882.51 ± 595.74 nmol g?¹ min?¹ per leaf dry weight. In terms of mean dark respiration rates, the values were: 0.51 ± 0.03 µmol m² s?¹ per leaf area, 85.68 ± 3.82 nmol g?¹ min?¹ per leaf fresh weight, and 787.14 ± 69.04 nmol g?¹ min?¹ per leaf dry weight.