Monotagma papillosum Hagberg & R.Erikss., 2011

Hagberg, Mats & Eriksson, Roger, 2011, New names in Monotagma (Marantaceae), Phytotaxa 20 (1), pp. 1-25 : 14

9. Monotagma papillosum Hagberg & R.Erikss. , sp. nov. ( Fig. 3A )

Bracteis roseis, synflorescentiae axe prinicipali nodis paucis, nodo inferiore folio frondoso instructo et laminae apice ± centrico Monotagmatis yapacanensi similis, sed ab eo differt lamina adaxiali pagina papillosa (vs. laevi), foliis caulinis pulvinis longioribus (2.4–4 vs. 1.1–2.1 cm) et laminis majoribus (35–51 vs. 25–36 cm longis), pedunculis florescentiarum lateralium brevioribus (ca 1 vs. ca 10 cm), et tubo corollae longiore (15–18 vs. 12–14 cm).

Type:— VENEZUELA. Amazonas: Tobogán de la Selva , 85 m, 19 April 1987, Hagberg & Medin 378 (holotype VEN, isotypes GB, INPA, MO, MYF, TFAV) .

Herb 1.5–2 m tall. Rhizomes subterraneous, branched to form clusters of up to ca 10 shoots, each shoot bearing 1–3 ± distichous basal leaves. Ultimate basal leaf with sheath 44–67 cm long, subcoriaceous to coriaceous, appressed-hirsute throughout, not auriculate; petiole 26–51 cm long, laterally ± flattened, without an adaxial groove, glabrous; pulvinus 3–4 cm long, laterally ± flattened, puberulent adaxially or ± glabrous, without annulus; blade ovate, ± chartaceous, base obtuse, apex acuminate, ± centric (apex displacement rarely up to 0.5 cm), 38–58 × 9.8–12 cm, length from base to broadest part 8–22 cm, adaxial surface papillose, matt green, appressed-hirtellous at apex, abaxial surface not papillose, greyish green, ± hirtellous at apex. Synflorescence 5–8-nodate with 9–30 florescences, lowermost node with a well-developed leaf, sheath 6–11 cm long, petiole 0.7–4.8 cm long, pulvinus 2.4–4 cm long, blade 35–52 × 6.5–12 cm, each subsequent node with a bladeless sheath, first internode 1.7–3.5 cm long, peduncle 90–140 cm long, glabrous. Main florescence 7.5–17 cm long, with 10–18 ± distichous bracts, first internode 0.7–1.1 cm long, peduncle 0.9–1.2 cm long; lowermost bract 1.8–2.1 × 0.8–0.9 cm, scarlet red, chartaceous, glabrous except for a tuft of hairs at apex; first prophyll 11–12.5 mm long, glabrous or slightly hirtellous at apex. Flowers 3–4 per bract; pedicel 0.5–1 mm long; ovary 1–2.5 mm long, puberulent to hirtellous throughout or rarely apically; sepals 7–9.5 × 1.5–2 mm, white, apex obtuse; corolla tube 15–18 × ca 1.5 mm, orange red towards lobes, base white, outside glabrous, inside hirsute in mouth, or rarely hirsute throughout except for a glabrous basal portion, lobes 4.5–5 × 2.5–3.5 mm, only slightly open, leaving a small pore at apex, red, dark red adaxially towards apex; outer staminode absent; stamen and inner staminodes orange red, stamen 4–5 mm long, appendage tapering to base of theca, theca 1–2 mm long; callose staminode 3.5–4 × 2.5–3.5 mm, fleshy throughout, with a shelf-shaped callus at 1–1.5 mm from apex; cucullate staminode 3.5–4 mm long, appendage 1 mm long; style 3.5–4 mm long (tripped). Capsule 14–16 × ca 3.5 mm; seed ca 14 × ca 3 mm; aril ca 4 mm long, with two flattened unilateral lobes.

Distribution and habitat:—Southern Venezuela (Amazonas), around Puerto Ayacucho. At the type locality it was found along streams in slightly disturbed primary forest with igneous outcrops, at 80–150 m elevation.

Discussion:— Monotagma papillosum is most similar to M. yapacanensis , from which it differs by having a papillose epidermis on the adaxial surface of the leaf blades (vs. smooth), a synflorescence leaf with longer pulvinus (2.4–4 vs. 1.1–2.1 cm) and usually longer blade (35–52 vs. 25–36 cm), lateral florescences with shorter peduncles (up to ca 1 vs. to ca 10 cm), longer bracts (1.8–2.1 vs. 1.5–1.7 cm), and longer corolla tubes (15–18 vs. 12–14 mm).

Paratypes:— VENEZUELA. Amazonas: Hills and base of hills near Cachama , 23 km NE of Puerto Ayacucho , April 1978, Davidse & Huber 15227 ( GB, MO) ; 23 km NE of Puerto Ayacucho , April 1978, Davidse & Huber 15400 ( MO) ; Tobogán de la Selva, February 1979, Plowman 7717 ( F, GB, K, NY) ; May 1977, Steyermark & Huber 113850 ( F, MO, VEN) ; May 1980, Steyermark et al. 122464 ( MO, VEN) ; September 1985, Steyermark et al. 131529 & 131564 ( GB, MO) ; March 1979, Trujillo & Pulido 15190 ( MY) . CULT. Lyon Arboretum (orig. from El Tobogán, Venezuela ) , December 1985, Nagata 3435 ( GB) .

Figures

FIGURE 3. Monotagma isotypes at GB. A, M. papillosum; B, M. remotum; C, M. humile; D, M. flavicomum.