Monotagma floribundum Hagberg & R. Erikss. 2011, sp. nov.
Creators: name: Hagberg, Mats
name: Eriksson, Roger
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Zingiberales
Marantaceae
Monotagma
Monotagma floribundum

description: 5. Monotagma floribundum Hagberg & R.Erikss., sp. nov.  (Fig. 2E)   
 Monotagmatis rhodanthi et M. rosei similis, sed ab eis differt nodo inferiore synflorescentiae folio frondoso (vs. vagina tantum) instructo, et lamina ad basin cuneata (vs. cordata); etiam M. densiflori et M. angustissimi similis, sed ab eis differt axe principali synflorescentiae nodis pluribus (10–11 vs. 4–7).   
 Type:— BRAZIL. Amazonas: Itaituba–Jacareacanga road, km 85, Parque Nacional do Tapajós (I. B. D. F.), Reserva Biológica Ramal do Pau Rosa, 14 November 1978, Silva & Rosario 3715 (holotype MG, isotype NY).   
Herb 1.5–2 m tall. Rhizomes subterraneous. Shoots bearing up to ca 7 distichous basal leaves. Ultimate basal leaf with sheath ca 80 cm long, ± coriaceous, appressed-hirtellous throughout, not auriculate; petiole 11–28 cm long, laterally ± flattened, without an adaxial groove, puberulent to rarely appressed-hirtellous; pulvinus 2–5.5 cm long, laterally ± flattened, appressed-hirtellous throughout, without annulus; blade narrowly oblong, ± subchartaceous when dry, base cuneate, apex acuminate, oblique (apex displacement 0.5–1.5 cm), 39–72 × 7.5–13 cm, length from base to broadest part 16–38 cm, adaxial surface not papillose, hirtellous to hirsute at apex, abaxial surface not papillose, hirtellous to hirsute throughout. Synflorescence 10–11-nodate with 15–60 florescences, lowermost node with a well-developed leaf, sheath 5–12 cm long, petiole 0–2.5 cm long, each subsequent node with a bladeless sheath, first internode 0.7–6.5 cm long, peduncle ca 120 cm long, appressedhirtellous to appressed-hirsute. Main florescence 4.4–8.3 cm long with 5–13 unilaterally arranged bracts, first internode 0.3–0.5 cm long, peduncle 0.4–0.6 cm long; lowermost bract 1.4–1.9 cm long, reddish, papyraceous, puberulent throughout or at least apically; first prophyll 10–11 mm long, glabrous or puberulent throughout. Flowers ca 3 per bract; pedicel 0.5–1 mm long; ovary 1–1.5 mm long, puberulent apically, rarely throughout; sepals 4.5–7 × ca 1 mm, apex obtuse; corolla tube 8.5–15 × 1–1.5 mm, outside towards lobes hirtellous to puberulent, rarely glabrous, inside hirtellous in mouth, lobes 3.5–5 × 2–3 mm, only slightly open, leaving a small pore at apex; outer staminode rudimentary or absent; stamen 3–3.5 mm long, appendage tapering to base of theca, theca 1–1.5 mm long; callose staminode 3–3.5 × ca 3 mm, 0.5–1 mm petaloid apically, with a shelf-shaped callus at 1.5–2 mm from apex; cucullate staminode 3.5–4 mm long, lateral appendage 1–1.5 mm long; style ca 3.5 mm long (untripped), or 3–3.5 mm long (tripped). Capsule 7–11.5 × 3–4 mm; aril with two flattened unilateral lobes.  
 Distribution:— Brazil, in the eastern part of the lowland Amazon Basin.   
 Discussion:— Monotagma floribundum usually has rudimentary (<0.5 mm long) outer staminodes. It is most similar to M. rhodanthum and M. roseum, from both of which it differs by having a leaf blade subtending the synflorescence (vs. a bladeless sheath) and cuneate leaf blade bases (vs. cordate). It is also similar to M. densiflorum and M. angustissimum, from which it differs by having a more richly branched synflorescence (10–11 vs. 4–7 nodes).   
 Paratypes:— BRAZIL. Amazonas: 4 km S of Terra Preta, Rio Abacaxis, July 1983, Hill et al. 12967 (INPA); Manicoré, August 1976, Mota s. n. (INPA); Manaus–Porto Velho road km 498, October 1983, Rodrigues 10454 (INPA). Pará: Rio Tapajós, morros de Quataguara (Coatáqurá), Ducke s. n. (RB); Rio Madeira, Rio Abacaxis, October 1957, Fróes 33667 (IAN); Monte Dourada, November 1978, Pires & Silva 1463 (GB); Santos 424 (MG, NY).
description: Published as part of Hagberg, Mats & Eriksson, Roger, 2011, New names in Monotagma (Marantaceae), pp. 1-25 in Phytotaxa 20 (1) on page 11, DOI: 10.11646/phytotaxa.20.1.1, http://zenodo.org/record/4776634