Anthurium renteriae Croat

CATE Araceae, 17 Dec 2011. araceae.e-monocot.org

General Description

Epiphyte, rooting at the nodes; internodes short, c. 1.5 cm diam.; cataphylls membranaceous, reddish brown, persisting intact, to 16 cm long. Leaves erect; petiole terete, 26–29 cm long, 4–5 mm diam.,  geniculate; geniculum c. 1.5 cm long, paler than petiole; blade narrowly oblong-ovate, cuspidate at apex, weakly subcordate at base, 38–41 cm long, 7.8–9.1 cm wide, averaging 40 × 8.5 cm, 4.5–5 × longer than wide, 1.4–1.5 × as long as petiole, subcoriaceous, drying greyish brown and weakly glossy above and below, only slightly paler below; midrib raised and concolorous above, rounded and slightly lighter than the surface below; primary lateral veins 12–14 pairs, rising at 40–50° angle, weakly raised
above and below; tertiary lateral veins  prominulous; collective veins arising from the 1st pair of basal veins, 3–4 mm from margin; basal veins 3 pairs, all free to the base, the 1st pair arching towards the apex and  forming the collective veins. Inflorescences erect; peduncle terete, c. 31 cm long, 3 mm diam.; spathe membranaceous, linear-lanceolate, c. 7.5 cm long, 8 mm wide, green; spadix sessile, cylindrical, c. 7 cm long, 8 mm diam., green. Flowers 1.4–1.6 mm long, 1.7–2 mm wide, sub-4-lobed, 10 visible per spiral; tepals shield-shaped, drying greyish, matte, granular, lateral tepals 0.8–1 mm wide, outer margin 2–3-sided; stamens held just above tepals, anthers 0.2 mm long, 0.4 mm wide, thecae almost rounded, not divaricate.

Distribution

Endemic to Colombia, known only from the type collection in Chocó Department.

Habitat

Tropical rain forest life zone.

Diagnostic

The species is a member of Anthurium sect. Calomystrium and is characterised by its epiphytic habit, short internodes, persistent, intact, reddish brown cataphylls, long petioles, narrow, ± oblong, greyish-drying leaves with rounded or weakly subcordate leaf bases as well as by the long-pedunculate inflorescence with a green spathe and spadix.

Anthurium renteriae is similar to A.  chromostachyum Croat from Panama, but that species differs in drying brownish rather than greyish, in having narrowly rather than broadly rounded, short posterior lobes and flowers that are about as long as broad, 13–15 visible per spiral with triangular, coarsely pale pustular with stamens all persisting tightly clustered over the stigma just above the tepals and with oblong anthers. In contrast, there are only 10 flowers visible per spiral in A. renteriae, they have greyish-drying tepals, the stamens are  scattered, not all held together in a tight cluster, and the anthers are oblong.