Monotagma flavicomum Hagberg & R.Erikss., 2011

Hagberg, Mats & Eriksson, Roger, 2011, New names in Monotagma (Marantaceae), Phytotaxa 20 (1), pp. 1-25 : 17-18

12. Monotagma flavicomum Hagberg & R.Erikss. , sp. nov. ( Fig. 3D )

Differt a speciebus caeteris Monotagmatis pilis longis flavis. Monotagmatis smaragdini similis sed ab eo differt lamina omnino viridi (vs. variegata) et corollae tubo breviore (17 vs. 25–27 mm longo); etiam M. aurantispathi similis sed ab eo differt pulvino longiore (0.9–1.3 vs. 0.5–0.7 mm in folio basali superiore), bracteis ad anthesin patentibus (vs. imbricatis) et staminodio exteriore spathulato (vs. elliptico).

Type:— PERU. Loreto: Jenaro Herrera, ca 1.5 km N of the Centro Agroforestal Camp , 120 m, 25 February 1987, Hagberg, Medin & Watson 375 (holotype AMAZ, isotypes F, GB, HHAP, NY) .

Herb 0.4–1 m tall. Rhizomes subterraneous, branched to form clusters of up to ca 10 shoots, each shoot bearing 4–11 irregularly arranged basal leaves. Ultimate basal leaf with sheath 17–29 cm long, subchartaceous to chartaceous, hirsute throughout, not auriculate; petiole 7.5–35 cm long, laterally flattened, hirsute; pulvinus (0.5–) 0.9–1.3 cm long, laterally flattened, hirsute throughout, without annulus; blade narrowly elliptic, ± papyraceous, scalloped, base obtuse, apex caudate, ± centric, 26–30 × 8.5–10 cm, length from base to broadest part 9.5–12.5 cm, adaxial surface usually not papillose, matt green, hirtellous to hirsute throughout, abaxial surface not papillose, greyish green, hirsute throughout. Synflorescence 2–3-nodate with 3–7 florescences, lowermost node with a well-developed leaf, sheath 8–11 cm long, petiole 0.5–6.7 cm long, pulvinus 0.6–0.8 cm long, blade 15–26 × 7.5–8.3 cm, each subsequent node with a bladeless sheath, first internode 3.2–6.3 cm long, peduncle 14–64 cm long, hirsute. Main florescence 4.8–14 cm long with 6–20 usually unilaterally arranged bracts, first internode 0.5–1.1 cm long, peduncle 0.9–2.1 cm long; lowermost bract 2.2–2.6 × 0.9–1.1 cm, yellowish green, chartaceous, hirsute throughout; first prophyll 12.5–16.5 mm long, hirtellous throughout or puberulent on back and at apex. Flowers 7–16 per bract, white; pedicel 0.5–1.5 mm long; ovary 2–2.5 mm long, glabrous throughout or puberulent apically; sepals 8–10.5 × 1–2 mm; corolla tube ca 17 mm long, outside glabrous, inside hirtellous except for a glabrous basal portion, or hirtellous in mouth, lobes 4.5–5.5 × 2–3 mm; outer staminode ca 7 × ca 5.5 mm, spathulate, emarginate; stamen 3.5–4.5 mm long, theca ca 1 mm long; callose staminode 3.5–6 × 2.5–5 mm, 1–2 mm petaloid apically, with a shelfshaped callus at 2–3 mm from apex; cucullate staminode ca 3.5 mm long, appendage 0.5–1 mm long; style 3– 3.5 mm long (tripped). Capsule 17–19 × 3–4 mm; seed 15–18.5 × 3–3.5 mm, dark red, ± cylindrical; aril 3–4 mm long, beige, tubular without lobes.

Distribution and habitat:—Known from Jenaro Herrera on the Río Ucayali, Peru, and from Serra da Moa near Cruzeiro do Sul, Brazil. At the type locality it was growing in a primary lowland forest with thick humus layer on white sand.

Discussion:— Monotagma flavicomum is readily recognized by its long yellow hairs. It is most similar to M. smaragdinum , from which it differs by having plain green leaves (vs. variegated) and shorter corolla tubes (ca 17 vs. 25–27 mm). It is also similar to M. aurantispathum , from which it differs by having a longer pulvinus on the ultimate basal leaf (0.9–1.3 vs. 0.5–0.7 cm), bracts spreading during anthesis (vs. imbricate), and spathulate outer staminodes (vs. narrowly elliptic).

The Brazilian collections have a longer synflorescence peduncle, three synflorescence nodes, and shorter florescences, but agrees with the Peruvian ones in all other respects.

Paratypes:— BRAZIL. Acre: Cruzeiro do Sul, slopes of Serra da Moa , April 1971, Prance et al. 12104 ( GB, INPA, K, L, NY) ; Bacia do Alto Juruá, Rio Moa , May 1996, Silveira et al. 1269 ( GB, NY) . PERU. Loreto: Jenaro Herrera , Río Ucayali, February 1987, Gentry et al. 56137 ( MO) ; February 1987, Gentry et al. 56334 ( MO) ; February 1987, Hagberg & Medin 369 ( AMAZ, GB, HHAP) ; November 1988, Maas et al. 6343 ( GB, L) ; August 1988, van der Werff et al. 10032 ( GB, MO) ; Requena, January 1984, Vásquez & Jaramillo 4740 ( GB, MO) .

Figures

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