Anthurium superimpendens López-Flor., Marco Correa & Zuluaga, 2023

López-Floriano, Oscar Mauricio, Correa-Munera, Marco A., Escalante, Daniela Villamizar- & Trochez, Alejandro Zuluaga, 2023, New Species Of Anthurium Schott Sect. Xialophyllium (Schott) From The Eastern Slope Of The Andes In Colombia, Phytotaxa 607 (4), pp. 249-254 : 250-253

Anthurium superimpendens López-Flor., Marco Correa & Zuluaga , sp. nov. ( Figs. 1 , 2 )

Anthurium superimpendens is characterized by its epiphytic habit with pendent stems and leaves, internodes short, 1.2–2.0 cm long, cataphylls persisting intact, blades narrow oblong-elliptic, 24.4–28.5 × 2.8–3.9 cm, primary lateral veins arising at an angle of 25°–35°, inflorescences pendent with a spathe adpressed to the stipe, oblong–lanceolate reddish brown, and an elongated stipe, 12.7–13.1 cm long.

Type: — COLOMBIA. Caquetá: municipality of Florencia, Corregimiento El Caraño , Vereda La Ruidosa , 1°52’17.34 N, 75°40’2.95’’ W, 2197 m, 1 November, 2021, Oscar López-Floriano, Marco Correa, Albeiro Moreno, Claudia Ortiz, John Camargo, Nasly Cutiva, Juan 215 (holotype HUAZ!, isotypes CUVC!, COL!) .

Epiphytic herb, stems pendent; internodes short 1.2–2.0 cm long, 3.8–4.0 mm diam. (All measurements were made on dry material unless otherwise mentioned); cataphylls 3.9–8.3 cm long, pale green, 1-ribbed, acuminate to apex, persisting intact at nodes, drying reddish brown. Leaves pendent; petioles 7.0– 10.7 cm long, 1.1–2.1 mm diam., light green, drying light brown, glabrous, terete, sheathed 4.6–5.1 cm, 42–50 % of its total length; sheath decurrent towards the apex of the petiole, the apex of the sheath acute; geniculum purplish red, 1.0– 1.5 cm long, 1.1–2.3 mm diam.; blades oblong-elliptic, 24.4–28.5 × 2.8–3.9 cm, 6.3–8.7 times larger than wide, 0.3–0.4 times larger than the petiole, glabrous, obtuse at base, long-acuminate at apex, coriaceous, discolorous, adaxial surface dark green, drying dark yellow green, abaxial surface pale green, drying light dull green; midrib acute and slightly raised on the adaxial surface, convexly raised on the abaxial surface; primary lateral veins 13–15 per side, arising at an angle of 25°–35°, prominent abaxially; collective veins arising at base of the blade, as prominent as the primary lateral veins, 0.4–0.6 cm from the margin; tertiary veins conspicuous. Inflorescence pendent; peduncle 7–9 cm long, 0.9–1.4 mm diam. (11.2 cm long, 2.3 mm diam. in vivo, terete, reddish brown, drying dark brown; spathe covering the base of the stipe, oblong-lanceolate 6.2–6.9 × 0.5–0.6 cm, reddish brown, drying light brown, abruptly acuminate at apex; spadix (measurements of flower and fruits taken from an inflorescence preserved in alcohol) bluntly tapered towards the apex, 5.9–7.4 cm long, 2.4–2.7 mm diam. at base, 1.5–1.6 mm in diam. at apex, greenish brown, drying very pale creamy brown; stipe elongated, 12.7–13.1 cm long, 2.2 mm diam. in vivo, drying 0.9–1.1 mm diam., terete, reddish brown; flowers 3–4 visible per spiral, 1.4–2.5 × 1.7–1.9 mm., rhombus-shaped flowers; lateral tepal 0.7 × 0.6 mm, posterior tepal 1.0 × 0.8 mm, anterior tepal 1.1 × 0.7 mm. Infructescence 7.5 cm long, 5.1 mm diam. at base, greenish brown, berries emerging; berries obovoid, light green, 2 mm long, 1.6 mm in diam., two seeds per berry; seeds cream color, ellipsoid, 1.3 mm long, 0.7 mm in diam., 1 per locule.

Etymology: —The name “superimpendes” (meaning overhanging) refers to the growth form of the plant, pendent from the host, and to its pendent inflorescences which have an elongated stipe, longer than the spadix, an uncommon character in the genus.

Distribution and ecology: — Anthurium superimpendens is only know from the type locality in the eastern slopes of the Andes mountain range, in the Caquetá Department of Colombia, where few individuals have been recorded ( Fig. 3 ). It grows in disturbed forests and was found growing on a tree of the genus Chrysochlamys , at an elevation of 2197 m, in lower montane wet forest according to Holdridge et. al. (1971) ( Fig. 2 ).

Taxonomic notes: — Anthurium superimpendens is a member of the section Xialophyllium for its elongated stems, long internodes, leaf blades longer than wide, and inflorescences with pistils that are not prominently exserted before the anthesis. Within Xialophyllium it can be confused with A. stipitatum and A. mindense but differs from those two species by its inflorescence with the spathe adpressed to the stipe (vs. erect-spreading), and an elongated stipe, 12.7–13.1 cm (vs. 2–5 cm). Additionally, A. superimpendens differs from A. stipitatum by the epiphytic habit (vs. terrestrial), stems pendent (vs. terrestrial with climbing branches), petioles 7.0– 10.7 cm long (vs. 12.70–15.24), blades 24.4–28.5 × 2.8–3.9 cm (vs. 15.24–20.32× 5.08 cm), blades drying dark yellow-green in adaxial surface and light dull green in abaxial surface (vs. reddish brown in both surfaces), primary lateral veins arising at an angle of 25–35° (vs. primary lateral veins arising at an angle of 62–80°), spathe reddish brown (vs light green), and spadix greenish brown (vs spadix purple). Finally, A. superimpendens differs from A. mindense by its shorter internodes 1.2–2.0 cm long (vs. internodes 1–12 cm long), cataphylls persisting intact at nodes, drying reddish brown (vs. cataphylls drying reddish, bases persisting in fibers), leaves thinner, 2.8–3.9 cm width (vs. 4–12 cm), leaves drying dark yellow green in adaxial surface and light dull green in abaxial surface (vs dark greyish brown in adaxial surface and light greyish brown in abaxial surface), inflorescence with spathe covering the stipe, reddish brown (vs. spathe erect to spreading or reflexed, cream, pale to medium green, or yellow green), spadix greenish brown (vs. green becoming dark purple, or greenish orange, green towards tip), stipe elongate, 12.7–13.1 cm vs 0.4 cm), infructescence with berries light green (vs berries orange-red).

Figures

FIGURE 1. Anthurium superimpendens. (A) Habit; (B) Internodes showing intact cataphylls; (C) Cataphylls; (D) Leaf blades, adaxial and abaxial surfaces; (E) Inflorescence; (F) Stipe with spathe; (G) Spadix; (H) close-up to flowers; (I) Extended spathe.

FIGURE 2. Plant habit in situ (A), Understore habitat where Anthurium superimpendens was recorded (B).

FIGURE 3. Location of Anthurium superimpendens in Vereda La Ruidosa, county Florencia, Caquetá department, Colombia.