Phyllanthus novofriburgensis J.C.R.Mendes, J.M.A.Braga & Fraga, 2024

Mendes, Jone Clebson Ribeiro, Braga, João Marcelo Alvarenga, Fraga, Claudio Nicoletti de & Athiê-Souza, Sarah Maria, 2024, Phyllanthus novofriburgensis and P. pedrosae, two new species of Phyllanthus subsect. Clausseniani (Phyllanthaceae) from Southeastern Brazil, European Journal of Taxonomy 935, pp. 293-306 : 295-298

Phyllanthus novofriburgensis J.C.R.Mendes, J.M.A.Braga & Fraga sp. nov.

urn:lsid:ipni.org:names:77342725-1 Figs 1A‒F , 2–3 ; Table 1

Diagnosis

Diagnostic characteristics in relation to other species in the subsection: herbaceous to subshrubby habit, 0.6‒1 m tall, pendulous. Stem rugose. Leaf blade 10‒30 × 5‒9.5 mm, lanceolate, base and apex obtuse, apex sometimes mucronate, margin revolute. Staminate pedicel 1.8‒2 mm long and pistillate pedicel 3‒5 mm long. Staminate disc surface slightly papillose.

Etymology

The specific epithet is based on the type locality.

Type material

Type BRAZIL – Rio de Janeiro • Nova Friburgo, Ponte da Saudade, R. Antiga Linha Férrea, 200 m da Fábrica Ypu, Inselbergue ; 22°18′20″ N, 42°31′27″ W; 868 m a.s.l.; 28 Sep. 2021; fl., fr.; J.C.R. Mendes & J.M.A. Braga 233 ; holotype: PEUFR [ PEUFR55897 !]; isotypes: MBML, RB .

Paratypes BRAZIL – Rio de Janeiro • Nova Friburgo; 14 Feb. 1984; fl.; E. Costa 258; RB • ibid.; 1 Oct. 2007; fl., fr.; L.J.S. Pinto et al. 1142; RB • ibid.; 28 Oct. 2005; fl., fr.; L.J.S. Pinto & M.G. Santos 792; RB • ibid.; 26 Nov. 2004; fl., fr.; A.F.P. Machado & L.J.S. Pinto s.n.; RB [412853].

Description

Herb to subshrub 0.6‒1 m tall, pendulous, monoecious. Stem cylindrical, rugose, glabrous. Cataphylls present. Branching non-phyllanthoid. Branches erect, sometimes flexuose, cylindrical, rugose, glabrous, pinnatiform; stipules ca 2 mm long, triangular, glabrous. Petiole 2‒2.2 mm long, cylindrical, glabrous. Leaf blade 10‒30 × 5‒9.5 mm, membranaceous, lanceolate; base obtuse; apex obtuse, sometimes mucronate; adaxial and abaxial sides glabrous, adaxial side dark green and abaxial side light green; margin revolute; venation brochidodromous, 8‒9 pairs of secondary veins. Inflorescence a simple cyme, axillary, bisexual; cymules with 2 staminate flowers and 1 pistillate flower arranged along the branch; bracts up to 1 mm long, triangular. Staminate flowers with pedicel 1.8‒2 mm long; sepals 5, 1.5‒2 × ca 1 mm, uniseriate, obovate, apex largely obtuse, glabrous on both sides, whitish, midrib not very evident; glandular disc 5-segmented, alternisepalous, obtriangular, surface slightly papillose; stamens 3, filaments completely free, up to 1.2 mm long; anthers deeply emarginate, with oblique dehiscence; pollen grains 4-colporate. Pistillate flowers with a 3‒5 mm long pedicel; sepals 5, 2‒2.2 × ca 1 mm, uniseriate, orbicular, apex obtuse, glabrous on both sides, whitish-green, midrib evident; glandular disc entire, cup-shaped, smooth; ovary up to 1 mm in diam., 3-locular, depressed globose; styles 3, free at base, 1‒1.5 mm long; stigma 2-fid, descending, subcapitate. Capsules 1.8‒2 mm in diam., 6-mericarp, light green, glabrous, calyx and stigma persistent; fruit pedicel 2‒2.3 mm long. Seeds 1‒1.2 mm long, trigonous; hilum terminal, obtriangular; verrucose ornamentation with regularly arranged stellate ribs; light brown.

Distribution, habitat and phenology

Phyllanthus novofriburgensis sp. nov. is found in the phytogeographic domain of the Atlantic Forest in the city Nova Friburgo, state of Rio de Janeiro, Brazil, growing under rocky walls (inselberg), in altitudinal ranges between 868 and 1267 m ( Fig. 3 ). It was collected with flowers and fruits in September, October and November and only with flowers in February.

Preliminary conservation assessment

Phyllanthus novofriburgensis sp. nov. falls into the Critically Endangered (CR) category, sub-criterion B1+B2 ab(iii,iv), due its range size (EOO) of 7 km 2 and AOO of 4 km 2. We classified it in this category because the species is restricted to a single rocky wall where an old train line is located. The surrounding area faces intense demographic pressure and anthropization. Consequently, we anticipate an imminent threat to the conservation of P. novofriburgensis .

Figures

Fig. 1. A‒F. Phyllanthus novofriburgensis J.C.R.Mendes, J.M.A.Braga & Fraga sp. nov. A. Branches. B. Leaf blade. C. Cymule. D. Staminate flower. E. Pistillate flower. F. Capsule. G‒M. Phyllanthus pedrosae J.C.R.Mendes, J.M.A.Braga & Fraga sp. nov. G. Branches. H. Branch detail [angular]. I. Leaf blade [in detail the mucronate apex]. J. Staminate flower. K. Pistillate flower. L. Capsule. M. Seed. Illustration designs based on type specimens by Regina Carvalho.

Fig. 2. Phyllanthus novofriburgensis J.C.R.Mendes, J.M.A.Braga & Fraga sp. nov. A‒B. Habitat. C‒D. Branches (in detail the staminate and pistillate flowers). E. Capsule. Photos by J.C.R. Mendes (A, B, C, E) and R. Freitas (D with staminate flower detail).

Fig. 3. Distribution map of Phyllanthus novofriburgensis J.C.R.Mendes, J.M.A.Braga & Fraga sp. nov. (white square) and P. pedrosae J.C.R.Mendes, J.M.A.Braga & Fraga sp. nov. (white circle). State abbreviations: ES = Espírito Santo; MG = Minas Gerais; RJ = Rio de Janeiro; SP = São Paulo.