Cardamine occulta Hornem.

Raab-Straube, Eckhard von & Raus, Thomas, 2025, Euro + Med-Checklist Notulae, 18, Willdenowia 55 (1), pp. 107-144 : 117

Cardamine occulta Hornem. (≡ Cardamine flexuosa var. occulta (Hornem.) O. E. Schulz ) – Fig. 8.

A Cm: Crimea: Sevastopol, Repina Str., Yuri Gagarin Park, 44°35'56.4"N, 33°29'32.6"E, 37 m, lawn, 24 & 27 Mar 2024, Yevseyenkov (YALT; photos [ Fig. 8]); ibid., Yalta, Sovetskaya Square, 44°29'56"N, 34°10'09"E, 10 m, flowerbed, 16 Apr 2024, Ryff (YALT). – The native range of C. occulta is S and E Asia. The spontaneous occurrence of this species in Europe was first recorded in 1977 ( Šlenker & al. 2019; Torun & al. 2023). Since then, the species has spread widely across the continent, especially in W, C and S Europe ( Marhold 2011b +; POWO 2024d). It is known to occur in regions adjacent to Crimea, viz. Turkey, the Caucasus and Ukraine ( Torun & al. 2023; Shynder & al. 2024; GBIF 2024a). Cardamine occulta prefers damp habitats such as banks of reservoirs, lawns and flowerbeds with regular irrigation, as well as greenhouses. This species was introduced to Crimea in recent years, apparently with planting material of ornamental plants; its populations are small and it is still a casual alien there. Cardamine occulta differs from the related native species C. hirsuta L. by an ascending, pubescent stem, branched from the base (vs usually simple, straight and glabrous in C. hirsuta ), an almost complete absence of compact basal leaf rosettes, and 6 stamens (vs 4 stamens in C. hirsuta ) ( Šlenker & al. 2019; Torun & al. 2023). L. E. Ryff & P. E. Yevseyenkov