P. involucrata Link & Otto ex Sweet
Section Sphondylia
Type Specimen:Bot. Mag. t2842. 1828.
P. boveana : nom. illeg.
P. verticillata Forssk. ssp. boveana (Duby) (syn): W.W.Sm. & Forrest, Notes Roy. Bot. Gard. Edinburgh. 16: 43. 1928.
Epithet: Named for the whorl of bracts surrounding the inflorescence.
Distribution: Egypt.
This species has been known by the name P. boveana Decne. ex Duby in DC, Prodr. 8:34 (1844) but previous to that, Sweet listed P. involucrata in Sweet's Hortus Britannicus 3:562 1839 referring to the type in Bot. Mag. t2842. 1826 (s/b 1828). This type describes a specimen raised from seed which had come from Otto, at the botanic garden at Berlin and which had been marked "Egypt". The "L.O." after the name "P. involucrata" in the Sweet catalogue refers to Link and Otto, Abbildungen et Beschreibungen seltener Pflanzen im Berl. Garten. Berlin 1821 (t. 51). The plant described in Link and Otto was a collection made by Ehrenberg at St. Catherine, Mount Sinai.
A plant endemic to four sites in the area of St Catherine's Mount, Sinai, Egypt growing near springs or in caves. It is the only member of this Section found in Egypt. Somehwat similar to P. verticillata, but smaller and mealy with bluntly pointed leaves.
