Thaumatococcus flavus A. C. Ley, 2012

Ley, Alexandra C. & Classen-Bockhoff, Regine, 2012, Five new species of Marantaceae endemic to Gabon, Adansonia (3) 34 (1), pp. 37-52 : 44

Thaumatococcus flavus A. C. Ley , sp. nov.

( Figs 1 ; 6 )

Thaumatocco daniellii similis sed inflorescentiae rhachidi fusca, bracteis floribusque, flavis bracteis pubescentibus, fructu juveni fusco cum verrucis, maturo rubro praecipue differt. TYPUS. — Gabon. Monts de Cristal, Tchimbele, in primary forest below the hydroelectrical station near the esplanade, 0°36.855’N, 10°24.159’E, 14.XI.2004, A. C. Ley 56 (holo- WAG!; iso- LBV!) .

PARATYPI. — Gabon. Monts de Cristal , Tchimbele, in the closed forest below the hydroelectrical station near the esplanade, 0°36.855’N, 10°24.159’E, 10.XII.2005, A. C. Ley 201, 202 ( LBV, WAG) . — Forest below airstrip towards the river, 0°37’30.6”N, 10°23’51.8”E, 13.XII.2006, A. C. Ley 218 ( LBV, WAG) . — Mikongo , 0°35.815’N, 11°12.413’E, 19.XI.2008, A. C. Ley 457 ( BRLU, LBV) . HABITAT AND DISTRIBUTION. — Primary forest along streams at around 500 m in Monts de Cristal in Gabon (Fig. 3) .

DESCRIPTION Rhizomatous herb, up to 2.5 m tall, forming clusters. Leaves arising solitary from rhizome; shoot base with sheaths of up to 20 cm in length, glabrous; petiole up to 2.5 m long, green, glabrous; pulvinus 10 cm long,glabrous; leaf lamina almost round, only slightly asymmetric,up to 40 × 30 cm, with a short broad tip, almost equally light green on both sides, pronounced parallel veins. Inflorescence arising from rhizome, up to 20 cm long, 2-3 partial inflorescences; peduncle 10 cm long with 2-4 sterile yellow bracts at the base of each branch; inflorescence axis brown, pubescent; internodes 3 cm at the base, 0.8 cm at the tip, long hairs around nodes; fertile bracts up to about 14 per partial inflorescence, yellow, about 22 mm long, pubescent; only one flower pair per bract; prophyll missing; axis of flower pair 1 mm, glabrous;pedicelles 0.5 and 1 mm long, glabrous, bearing one bracteole each, 1.5 × 0.9 mm, brown. Flower yellow, 2.5 cm long;sepals 12 × 3 mm; petals 28× 7 mm folded backwards; corolla tube about 15 mm; outer staminodes mostly absent, about 23 cm long; cucullate staminode about 25 mm long;callose staminode 24 mm; stamen 3 mm; petaloid appendage about 25 mm long; style about 30 mm long; ovary 3 × 2.5 mm, yellow/brown, pubescent.Fruit first brown then red at maturity, triangular, fleshy, surface verrucous, about 3.5 × 4 cm. Seeds white, 1.5 cm long.

REMARKS

Thaumatococcus flavus A.C. Ley , sp. nov. differs from the only other species in the genus, Thaumatococcus daniellii Benth. , in the colour of the inflorescence, bracts and flowers, the surface structure of the fruit and its restricted distribution range in the mountainous area of Monts de Cristal.

Figures

FIG. 1. — A-C, Hypselodelphys lopei A. C. Ley, sp. nov., inflorescence (A), flower (B) and fruit (C); D, E, Marantochloa montsdecristalii A. C. Ley,sp. nov., inflorescence (D) and flower (E); F-H, Marantochloa alba A. C. Ley,sp.nov., flower pair (F), habitus (G), inflorescence (H); I, J, Thaumatococcus flavus A. C. Ley, sp. nov., habitus (I), inflorescence (J); K-M, Marantochloa grandiflora A. C. Ley, sp. nov., habitus (K), inflorescence (L) and flower pair (M). Scale bars: 1 cm.

FIG. 6. — Thaumatococcus flavus A. C. Ley, sp. nov.: A, habitus with inflorescence arising from the rhizome bearing flowers and fruit; B, leaf; C, flower (note the long and narrow floral tube); D, fruit; E, open fruit with three seeds; F, seed cut in half. A-F, A. C. Ley 56. Abbreviations: br, bracteole; infl., inflorescence; o, ovary; p, petal; pa, petaloid appendage of fertile theca; pch, perispermatic channel; s, sepal; sd, seed. Scale bars: A, 10 cm; B-F, 1 cm.