Monotagma grallatum Hagberg & R.Erikss., 2011

Hagberg, Mats & Eriksson, Roger, 2011, New names in Monotagma (Marantaceae), Phytotaxa 20 (1), pp. 1-25 : 4-5

1. Monotagma grallatum Hagberg & R.Erikss. , sp. nov.

Synflorescentia congesta M. spicati et M. ovati similis , sed ab eis differt capsula majore (14–15 vs. 9–12 mm longa); differt fere a M. spicato internodio primo florescentiae longiore (0.8–1.1 vs. 0.3–0.9 cm) et corollae tubo longiore (21–27 vs. 17–23 mm); differt fere a M. ovato pedicello longiore (1.5–1.4 vs. 1.0– 1.5 mm) et lobis corollae brevioribus (4.5–5.5 vs. 5.5–8.0 mm).

Type:— BRAZIL. Espírito Santo: reserve of the Companhia do Vale do Rio Doce , E of BR-101, 20 km N of Linhares , ca 2 km E of administration buildings, 20 February 1986, Andersson, Hagberg & Mattos Silva 1715 (holotype CEPEC, isotypes GB, INPA, S, US).

Herb 0.4–1.7 m tall. Rhizomes of mature shoots trailing partly above ground (to ca 40 cm) and supported by “stilt” roots, branched to form clusters of 3–30 shoots, each shoot bearing 0–13 irregularly arranged to ± distichous basal leaves. Leaf sheath (7–) 9–36 cm long, with scarious reddish margins, chartaceous to subcoriaceous, appressed-hirsute to rarely appressed-hirtellous throughout, the sheath margins tapering in broad bows to petiole; petiole (6.6–)12–44(–53) cm long, terete or laterally ± flattened, with an adaxial groove, puberulent or ± glabrous; pulvinus (1.3–)2.1–4.6(–5.1) cm long, laterally ± flattened, puberulent adaxially, a prominent hirtellous annulus present at transition to petiole; blade narrowly ovate to elliptic, chartaceous to coriaceous, base obtuse to truncate, very rarely cuneate, apex acuminate to caudate, centric or oblique (apex displacement 0–5.2 cm), (21–)26–47 × (4–) 7–22 cm, length from base to broadest part 7–17 cm, adaxial surface not papillose, puberulent to hirtellous along midrib, major lateral veins and margins, and at apex, abaxial surface not papillose, glabrous or rarely appressed-puberulent at apex. Synflorescence 2–6- nodate with 4–25(–35) florescences, each node with a bladeless sheath, lowermost 3.2–8.3(–13) cm long, first internode 2.2–4.7(–5.3) cm long, peduncle (9.5–)12–21(–25) cm long, appressed-hirsute to appressedhirtellous or rarely glabrous to slightly puberulent. Main florescence 7.3–17.5 cm long, with 8–24 ± unilaterally arranged bracts, first internode 0.8–1.1 cm long, peduncle 0.9–1.3(–1.6) cm long; lowermost bract 2.4–3.2 × 0.8–1.0 cm long, dull orange, subcoriaceous, puberulent to hirtellous at apex and along margins or rarely throughout; first prophyll 14–18 mm long, puberulent to hirtellous on back and at apex, rarely hirtellous at base or glabrous, ecarinate; interphylls and bracteoles absent. Flowers 4–6 per bract; pedicel 1.5–4 mm long; ovary 2–3.5 mm long, puberulent apically or rarely throughout; sepals 12–19 × 2.5–3.5 mm, white; corolla tube 21–27 × 1–1.5 mm, whitish, outside glabrous or rarely slightly hirtellous towards lobes, inside hirsute except for a glabrous basal portion or at least hirsute in mouth, lobes 4–5.5 × 2.5–3 mm, whitish; outer staminode 5.5–7 × 2–3.5 mm, narrowly obovate, purplish, very rarely two ± equal staminodes, apex usually entire; stamen 4–5 mm long, appendage tapering to base of theca, theca 1–1.5 mm long; inner staminodes whitish to purplish; callose staminode 4.5–5.5 × 3–5 mm, fleshy throughout, with a shelf-shaped callus at 2.5– 3 mm from apex; cucullate staminode 4–5 mm long, appendage 1–1.5 mm long; style 4–5 mm long (untripped), or 3–4 mm long (tripped). Capsule 14–15 × ca 3.5 mm; seed 12.5–14.5 × 3–3.5 mm; aril 2.5–3.5 mm long, with two flattened unilateral lobes.

Discussion:— Monotagma grallatum is similar to M. spicatum and M. ovatum , from which it differs by having longer capsules (14–15 vs. 9–12 mm) and longer seeds (12–15 vs. 8–11 mm). It also differs from M. spicatum by usually having a longer first florescence internode (0.8–1.1 vs. 0.3–0.9 cm) and longer corolla tubes (21–27 vs. 17–23 mm), and from M. ovatum by having longer pedicels (1.5–4 vs. 1–1.5 mm) and shorter corolla lobes (4–5.5 vs. 5.5–8 mm).

Monotagma grallatum consists of two ± allopatric morphotypes which differ in leaf shape. The northern morphotype has small (21–29 × 4–11 cm), narrowly ovate to very narrowly ovate, centric to subcentric leaves, whereas the southern morphotype has large (36–47 × 16–22 cm), elliptic to ovate, ± distinctly oblique leaves. Since they do not show any differences in synflorescence and flower morphology, or habitat, and since they have ± allopatric distributions, we recognize them as subspecies.