Phyllanthus carmenluciae R.T.M. Ribeiro & Loiola, 2017

Ribeiro, Rayane De Tasso Moreira, Neto, Raimundo Luciano Soares & Loiola, Maria Iracema Bezerra, 2017, Phyllanthus carmenluciae, a supreme species of Phyllanthus (Phyllantaceae) from Brazil, Phytotaxa 305 (1), pp. 35-40 : 36

Phyllanthus carmenluciae R.T.M. Ribeiro & Loiola , sp. nov. ( Figs. 1–3 )

Type:— BRAZIL. Ceará: Sítio Jardim, Mulungu, Serra de Baturité, 4.481ºS, 39.018ºW, 740 m, 14 February 2003, A. P. Silveira 855 (holotype: EAC!, isotypes: EAC!, RB!).

Diagnosis:— Phyllanthus carmenluciae resembles P. niruri Linnaeus (1753: 981–982) , differing from the latter by having pubescent cylindrical branches (vs. glabrous), mucronate leaf apex (vs. rounded, not mucronate), inflorescences in bisexual cymules, with two proximal staminate flowers and two distal pistillate flowers (vs. unisexual cymules, staminate cymule with 2–4 proximal flowers and pistillate cymule with solitary distal flower), stamens completely united to form a column (vs. free to partially fused), anthers with vertical clefts (vs. anthers with horizontal to oblique clefts).

Description:— Herb ca. 30 cm tall, monoecious. Stems erect, cylindrical, main axis glabrous and with phyllanthoid branching. Branchlets pinnatiform, densely pubescent. Cataphylls 3, at the base of the branchlets, 1.2‒4.2 mm long, broadly triangular, apex acuminate. Stipules 2, 0.3‒1.4 mm long, triangular, apex acuminate, deciduous, escarious. Petiole 0.2‒0.5 mm long, cylindrical. Leaves 6‒15 × 3.7‒8.0 mm, simple, alternate; blades membranaceous, oblong, oblong-elliptic to obovate, base slightly cordate or truncated and asymmetric, apex obtuse to rounded and often mucronate, margin entire; venation brochidodromous, midvein slightly prominent and secondary veins impressed abaxially. Cymules bisexual axillary with 2 proximal staminate flowers and 2 distal pistillate flowers along the branchlets; bracteoles 2, ovate, 0.7‒1.1 mm long. Staminate flowers 2.0 × 2.5 mm; pedicel cylindrical, 5.0‒ 6.5 mm long; sepals 5, 0.7‒1.0 × 0.8‒1.0 mm, membranaceous, obovate, margin entire, apex rounded; petals absent; glandular disk ca. 1 mm diam., entire, fleshy, margins slightly undulate, 5-lobate; stamens 3, completely connate in column, ca. 1.4 × 0.5 mm, anthers sagittate, sessile at the apex of the column, vertical. Pistillate flowers ca. 1.7 × 1.4 mm; pedicel 4‒6 mm, cylindrical; sepals 5, ca. 0.6 × 0.5 mm, obovate, margin repand, apex rounded; glandular disk 0.7 mm diam., entire, 5-lobate, margins slightly undulate; ovary 0.6 × 0.7 mm, conical-ovoid, glabrous, tricarpellate, trilocular, ovules 2 per locule; ovules piriform, axial; style 3, free, bifid, curved, stigma capitate. Capsule 1.5‒2.0 × 1.4‒3.0 mm, subglobous, calyx and style persistent in fruit. Seeds 1.0‒1.3 × 0.4‒1 mm, trigonous; seed coat brownish, lucid, warty along longitudinal lines and transverse ribs.

Distribution and habitat:—The species is currently known only from the Serra de Baturité mountains, which are characterized by their dense ombrophilous forest vegetation ( IBGE 2012). The specimen was collected on a private property known as Sítio Jardim, in the municipality of Mulungu, Ceará State, Brazil, at> 700 m.

Phenology:—Flowering and fruiting in February.

Etymology:—The epithet honors the current president of the Brazilian Federal Supreme Court, Cármen Lúcia Antunes Rocha, an exemplary woman and capable judge who has fought, and still does, for justice in Brazil. The species described here produces small flowers and thrives under environmental conditions that are often quite adverse—mirroring the daily struggle for life and justice in Brazil. As such, this plant symbolizes to the first author all that is good about botany, law, and the magistrate being honored by the species epithet.

Conservation Status:—As this species is known only from its type locality and following recommendations from the IUCN (2012), we have classified P. carmenluciae as data deficient (DD). We have conducted more field excursions to sites near the type locality or to other areas with similar habitats but no additional specimens have been encountered.

Figures

FIGURE 1. Phyllanthus carmenluciae R.T.M. Ribeiro & Loiola (A.P. Silveira 855). A. Habit. B. Leaf, detail of mucronate apex. C. Branch with cataphylls. D. Branch and detail of trichomes. E. Staminate flower. F. Pistillate flower. G. Fruit. H. Seed, lateral view. (Drawing by F. M. Guedes).

FIGURE 2. Scanning electron micrographs of features of Phyllanthus carmenluciae (A.P. Silveira 855). A. Leaf, detail of adaxial surface. B. Branch, detail of trichomes. C. Staminate flower showing details of calix, disk and staminal column. D. Fruit. E. Seed trigonous in a frontal view. F. Detail of seed coat with verruculous along longitudinal lines and transverse ribs. Bars of 2 mm (A), 200 μm (B), 500 μm (C, D, E), 250 μm (F).