Niche differentiation of two congeneric Phlomis species in Egypt

Phlomis aurea Decne. and Phlomis floccosa D. Don. exhibit different ecological and geographical distribution range in Egypt. Phlomis aurea is endemic to Saint Katherine Protectorate (SKP), South Sinai with narrow geographic distribution, but wide ecological range. Phlomis floccosa has wide geographical and ecological range within the coastal western Mediterranean coast of Egypt. Unlike P. floccosa, P. aurea has wide altitudinal range which increases its resistance to climate changes. Here, we assessed the effect of microhabitats on growth parameters and plant vigor of P. aurea and P. floccosa. The maximum EC of the soil in the various microhabitats supporting P. floccosa (950 μS/cm) is substantially higher than that of P. aurea (110 μS/cm). Both Phlomis species had low number of associated species which may be related to habitat aridity. The results indicate that the microhabitats supporting both species are the best environments for future conservation of these species under the impact of climate change.