Arum rupicola Boiss.

Tuberous herb sprouting in early winter from a discoid, vertically orientated tuber 4-8 cm across, 2-3.5 cm thick. Petiole terete, 10-55 cm long, 3-6 mm wide, pale to mid-green. Leaf-blade oblong-sagittate to oblong-hastate, apex subacute to obtuse, occasionally rounded, 8-25 cm long, 4-18.5 cm wide, mid-green. INFLORESCENCE odourless. Peduncle exceeding the leaves, terete, 10-65 cm long, 4-12 mm wide, pale to mid-green. Spathe 11.5-40 cm long; spathe-tube oblong-cylindric, 2-7 cm long, 0.75-2.5 cm wide, moderately to strongly constricted apically, exterior pale to mid green, very rarely mid-brown, sometimes with purple staining along the margin at the top, interior white; spathe-limb linear-lanceolate to lanceolate, 9.5-33 cm long, 2-8 cm wide, erect at first but soon flopping either backwards or forwards and curling apically, margins sometimes crispate, acute to acuminate, externally pale to mid-green, often heavily stained with purple along the margin, sometimes ± entirely purple, rarely entirely green, very rarely mid-brown, internally pale greenish white ± stained with deep purple or maroon, more rarely greenish white with a very narrow purple margin, very rarely mid-brown. Spadix subequal to or exceeding the spathe-limb, 8-33 cm in total length; appendix cylindric to conic-cylindric , sometimes massively so, short-stipitate to almost stalkless , 6-32 cm long, 13-25 mm wide, deep to mid-purple to grey-lilac, rarely brown, dirty orange or yellow, often darkening rapidly on the opening of the inflorescence. Staminodes in 2 to 4 whorls forming a zone 2-10 mm long; bristles filiform, flexuous, 1.5-9 mm long, violet to deep purple; bases compressed conic, smooth, off-white. Interstices: upper and lower 0-2.5 mm long, usually with numerous rudimentary sterile flower bases, off-white. Staminate flowers in an oblong zone 3-25 mm long, 5-10 mm wide; anthers and connectives deep violet. Pistillodes in 2 or 3 or rarely 4 whorls; bristles filiform, flexuous, 1.5-9 mm long, violet to deep purple; bases compressed conic, smooth, off-white. Pistillate flowers in an oblong cluster 7-25 mm long, 5-17 mm wide; ovaries oblong-ovoid, 2-2.5 mm long, somewhat truncate apically, pale to mid-green, often stained with purple apically (this feature differing even within the same population); stigma purplish grey. Fruiting spike oblong-cylindric, 3-6 cm long, 1.5-2.5 cm wide when mature; berries ovoid, 5-11 mm long, 2-5 mm wide. Germination unknown.