Kickxia Dumort.
Genus composed of about 30 herbaceous or subshrubby species, distributed through Europe, North Africa and western Asia, especially in the Mediterranean and Irano-Turanian regions. In North Africa this genus is represented mainly by herbaceous species. Among the 4 slightly woody species, the one with the largest size is K. heterophylla, the other 3 species, which rarely exceed 0.5 m in height, are:
K. macilenta (Decne.) Danin & Hedge (Ara. Egypt: Halawa), is a subshrub that can reach 60 cm in height, distinguished by its small flowers (7.5-11 mm, including the spur), and by being covered by a characteristic pubescence with eglandular somewhat rigid hairs. As in K. gracilis, the capsules have a valvular dehiscence. It is endemic to the mountainous areas of the Sinai, Palestine and Israel.
K. scoparia (Spreng.) Kunkel, with herbaceous stems, somewhat woody at the base; it can reach up to 50(60) cm in height; it can be well differentiated by its linear leaves, less than 2 mm wide. Essentially of Saharo-Arabian distribution, reaching the Canary Islands in the W.
K. aegyptiaca (L.) Nábělek (Ara. Egypt: Eshb el-deeb, megeinina. Tamahaq: Amataltal) is a subshrub that barely reaches 50 cm in height, with old branches usually spinescent, corolla 12-15(18) mm long (including the spur) and capsules with operculate dehiscence. It is a very polymorphic species distributed in North Africa, the eastern Mediterranean and SW Asia; in North Africa it is found in rocky grasslands in arid, desert or subdesert areas of Morocco, Algeria, Tunisia, Libya and Egypt.
In North Africa, there is a woody subshrubby species (that can reach 75 cm in height) from a closely related genus to Kickxia: Anarrhinum fruticosum Desf. It differs from species of Kickxia, among other things, by having flowers arranged in terminal racemes with very short pedicels (1-1.5 mm), and capsules with poricidal dehiscence and not valvular or operculate dehiscence. Endemic to North Africa, it is found in rocky outcrops and scree in mountainous areas of the Sahara in Morocco, Algeria, Tunisia and Libya. It have 3 subspecies. The subsp. fruticosum, in Morocco and Algeria, the subsp. demnatense (Coss.) Maire, in Morocco, and the subsp. brevifolium (Coss. & Kralik) D.A. Sutton, in Tunisia and possibly also in the O of Libya.
K. scoparia and A. fruticosum are rare but widely distributed species. K. macilenta is rarer and with a much smaller distribution area. Currently, none have been assessed at a global level in the IUCN Red List of Threatened Species. In the Red List of vascular plants of Egypt (Flora Aegyptiaca Vol 1, 2000) K. gracilis is listed as “Vulnerable” and K. macilenta as “Rare”.
Several revisions have been made in the past decades to clarify the phylogenetic relationships between these and other genera of the Scrophulariaceae family, that might still undergo new changes, due to its complexity. Here, we follow the classification proposed in ISFAN (2013).
Ghebrehiwet, M., 2000. Taxonomy, phylogeny and biogeography of Kickxia and Nanorrhinum (Scrophulariaceae). Nordic Journal of Botany 20(6): 655-690.
Sutton, D. 1988. A revision of the tribe Antirrhineae. Oxford University Press, London & Oxford.
Key to species
1 Leaves linear, 1-2 mm wide Kickxia scoparia
1 Leaves not linear and more than 2 mm wide 2
2 Corolla with subequal lips. Capsule with an operculate dehiscence. Anthers ciliate Kickxia aegyptiaca
2 Corolla with unequal lips. Capsule with a valvular dehiscence. Anthers glabrous 3
3 Flowers 7.5-11 mm, with a spur as long as or somewhat shorter than the rest of the corolla. Capsule with 2 unequal cavities, one smaller and indehiscent or opening later than the other Kickxia macilenta
3 Flowers 18-28 mm, with spur much longer than the rest of the corolla. Capsule with 2 subequal cavities and opening almost simultaneously Kickxia heterophylla
Updated by: B. Valdés & J. Charco.