Heteropsis rigidifolia, Engl., Pflanzenr. IV.

12. HETEROPSIS RIGIDIFOLIA Engl. ,

Pflanzenr. IV. 23 B: 51. 1905.

— TYPE: BRAZIL. Santa Catarina, Blumenau, 1886, Schenk 815 (lectotype: B! fl, here designated).

Plant a scandent hemi-epiphyte; internodes 1.5–2 cm long, 3–4.7 mm diam, slightly striate longitudinally when dried, subquadrangular, flattened on one side, pale grey when dried; axillary buds ca. 2 mm long, rounded to truncate at the apex. Petiole 3–5 mm long, 2–6 mm diam, canaliculate, margin sinuate towards the apex; geniculum ca. 6 mm long; blade 14–22 cm long, 2–4 cm wide, linear to lanceolate, patent, strongly coriaceous, rigid, when dried greenish-brown on both surfaces, 0.21–0.48 mm thick, apex acute to acuminate, base cuneate to obtuse, midrib somewhat flattened on the adaxial side, with dispersed transverse striae, somewhat prominent on abaxial side, primary lateral veins and interprimary veins impressed on the adaxial side, prominent on the abaxial side, tertiary veins forming indistinct reticulations, submarginal collective vein 0.75–1 mm distant from the margin, external marginal vein 1, close to the submarginal collective vein. Inflorescence terminal and axillary, flowering shoot 7.5–20 cm long, with internodes 2–5 cm long, 2.8–3.5 mm diam, when dried greenish-brown, shallowly sulcate; peduncle ca. 2.5 mm long; spathe 2–3 cm long, ca. 2.5 cm wide, oblong, apex acuminate; spadix 1.5–3 cm long, 0.6–0.8 cm diam, subcylindric, apex acuminate, stipitate, stipe 0.75–2 mm + 1.4–2 mm. Gynoecium with apex 1.5–2 mm diam, stigma elliptic. Infructescence 7–9 cm long, 6 cm diam; berry to 10 + 8 mm, orange; seed subovoid, ca. 6–8 + 4–5 mm. Figures 2B View FIG , 23 View FIG .

Habitat and Distribution— Heteropsis rigidifolia is known only from the Atlantic Forest of Brazil (Bahia, Espírito Santo, Minas Gerais, Paraná, Rio de Janeiro, Santa Catarina, and São Paulo), where it occurs at 220–950 m alt.

Phenology— Flowering specimens have been collected between October and December, and fruiting material between January and February.

Conservation Status— Using guidance from the Geocat (2012) online tool, the preliminary conservation assessment of H. rigidifolia is least concern (LC), based on 13 localities and a 50 km cell width (auto value cell size option for area of occupancy).

Etymology— The specific epithet refers to the rather rigidly coriaceous leaves.

Notes— Heteropsis rigidifolia was described by Engler based on three syntypes: Loefgren & Edwall 1652 (B) from Peruibe, São Paulo, Mosén s.n. (S) from Santos , São Paulo and Schenk 815, (B) from Blumenau, Santa Catarina. Only one of these, Schenk 815, was found in this study, at the Berlin Herbarium (B), which we propose here as the lectotype. Heteropsis rigidifolia is easily recognized by its strongly coriaceous and rigid leaf blade with the veins prominent on both surfaces when dried. It is easily confused with H. salicifolia by the leaf shape with its cuspidate apex but differs from the latter by the truncate lateral buds, rigidity of the leaf blade, prominence of the veins and white spathe, which in H. salicifolia is greenish-yellow to cream. Furthermore, the leaf blade of H. rigidifolia is usually oblanceolate in the juvenile and climbing phases.

Additional Specimens Examined— BRAZIL. Bahia: Una, Reserva Biológica do Mico-Leão , 15 09 ' S 39 05 ' W, 14 Nov 1992, Thomas et al. 9447 ( K ster, MO, NY fl) GoogleMaps ; Parque Nacional de Monte Pascoal, 16 53 ' S 39 25 ' W, 11 Jan 1977, Harley et al. 17848 (K ster); 13 Jan 1977, Harley et al. 17921 (K ster); Wenceslau Guimarães, 31 Feb 1991, Mayo & F. A. Carvalho 862 (CEPEC, K, MO ster). Espírito Santo: Santa Teresa, Rio Bonito , 31 Jan. 202, Kollmann & Bausen 5454 ( MBML fr) ; 15 Feb 2000, Demuner & Bausen 717 (MBML fr). Minas Gerais: Marliéria, 13 Dec 2000, Temponi et al. 205 ( VIC ster) . Paraná: Antonina, 19 Jan 1966, Hatschbach et al. 13555 ( U ster) ; Curitiba, 1 Oct 1982, Hatschbach 33642 (MO fl); 24 Mar 1911, Dusen 11392 (K ster). Rio de Janeiro: 25 Jan 1998, Oliveira, 1424 ( GUA fr). Itatiaia, Parque Nacional do Itatiaia, 22 28 ' S 44 45 ' W, 7 Dec 1995, Braga et al. 3084 (RB fl); 21 Nov 1995, Nadruz et al. 1100 (RB fl); Parati, 20 Oct 1993, Marquete 1293 (RB fl). Santa Catarina: 2 Nov 1953, Reitz & Klein 1098 ( MO ster). Brusque, 10 Nov 1949, Reitz 3194 (U ster). São Paulo: Reserva Ecológica da Juréia , 19 Feb 1996, Costa et al. 127 (SP fr) ; 10 Mar 1982, Hatschbach & Kummrow 45527 (CEPEC, K ster); 28 Nov 1991, Rossi 950 (SP fl); 18 Dec 1990, Mamede et al. 382 (SP fl).