Behuria lumiarensis Bochorny, Michelang. & R. Goldenb., 2017

Bochorny, Thuane, Michelangeli, Fabian A. & Goldenberg, Renato, 2017, Behuria lumiarensis (Melastomataceae), a new species on a mountaintop of the Brazilian Atlantic Forest, Phytotaxa 305 (2), pp. 111-111 : 111

Behuria lumiarensis Bochorny, Michelang. & R. Goldenb. sp. nov. Figures 1–2

Diagnosis: Behuria lumiarensis is similar to Behuria cordifolia Cogniaux (1886:13–14) by the sessile glands on the adaxial surface of the leaf, the calyx tube size and the glabrous ovary apex. It can be distinguished by the smaller petals, 10–12 × 4–6 mm (versus 13–17 × 8–10 mm in Behuria cordifolia ) and narrower sepals, 0.5 mm (vs. 1–1.5 mm wide) that are not apiculate in the apex (vs. apiculate). Type: ― BRAZIL. Rio de Janeiro: Nova Friburgo, Distrito de Lumiar, Área de Proteção Ambiental Macaé de Cima, no topo da Serra Queimada, 22°22’58’’S – 42°17’36W, 1450 m, 22 January 2016, fl., fr., T. Bochorny, Bacci & Bolson 200 (holotype: UEC!; isotypes: NY!, UPCB!).

Shrubs 1–1.5 m tall; branches, petioles, inflorescences, bracts and bracteoles sparsely covered with stalked glands, 0.5–1 mm long (the heads sometimes caducous). Branches terete, striate. Leaves opposite; petioles 1–3 cm long; blades 2–10.2 × 1–5.5 cm, ovate or elliptic, apex acute or acuminate, base rounded or subcordate (the insertion of the petiole into the base of the leafy is revolute on the adaxial surface), margins serrulate, plane, chartaceous, adaxial surface sparsely covered with sessile glands, 0.2–0.4 mm long, abaxial surface moderately covered with stalked glands, 0.5–1 mm long, only on the veins, acrodromous veins 5, with an additional faint submarginal pair, basal, main veins impressed adaxially and raised abaxially, transverse veins and reticulation barely visible on both surfaces. Thyrsoids 4.2–5.3 cm long, apical, with 5–10 flowers, these usually arranged in congested triads, but sometimes depauperate; bracts two, persistent, leafy, 1–1.8 × 0.5–0.8 mm long, petioles 1.5–2 mm long, blades elliptic or broadly elliptic; bracteoles two, persistent, leafy, 1–2 mm long, sessile, lanceolate. Flowers 6-merous, on pedicels 1.5–2 mm long. Hypanthium 4–6 × 4 mm, campanulate, green, sparsely covered with stalked glands, 0.5–1 mm long. Calyx tube 1 × 4–5.5 mm, green, with the same trichomes as the hypanthium; sepals 7–9 × 0.5 mm, green with pinkish apices, linear to very narrowly triangular, margins ciliolate (the cilia sometimes caducous), apex not apiculate, glabrous; external teeth absent. Petals 10–12 × 4–6 mm, left margin (in adaxial view) white, entire, right margin (in adaxial view), white to pinkish, obovate and asymmetric, apex rounded to emarginate, margin entire, not apiculate, both adaxial and abaxial surfaces glabrous. Stamens 10 to 12, yellow, subisomorphic, glabrous; filaments 6–10 mm long (antesepalous) or 4–8 mm long (antepetalous); connective not prolonged below the thecae, dorsal appendages ca. 3 mm long, yellow and pinkish in the apex, linear-subulate; anthers 3–4 mm long in both cycles, yellow, oblong-linear, the thecae prolonged up to 0.3 mm below the insertion of the filament, with a single, apical (but ventrally inclined) pore. Ovary 3–6 mm long, 2/3 basally adhered to the hypanthium, 4-locular, apex glabrous, without extended lobes; style 9–11 mm long, slightly curved or sigmoidal, glabrous. Capsules 5–8 × 6–8 mm, the carpels exceeding the hypanthium length by 1mm; seeds 1.5 × 0.5 mm, elongate or oblong, raphe almost equaling the seed length, testa granulate.

Distribution, ecology and phenology: ― Behuria lumiarensis has been collected only once at the hilltop of “Serra Queimada” peak (1.450 m elev.; see figure 3), in the district of Lumiar, municipality of Nova Friburgo, central Rio de Janeiro state. The “Serra Queimada” peak is located inside the region of Macaé de Cima Environmental Protection Area (“Área de Proteção Ambiental Macaé de Cima”), a partially protected area managed by the state. With 35.038 ha, it was established in September 2001 ( INEA 2016) and is mostly covered with montane Atlantic rainforest (“Floresta Ombrófila Densa Submontana/ Montana ”, following the official classification for Brazilian vegetation; IBGE 2012). This region includes a significant proportion of secondary vegetation, where wildfires are frequent (as suggested by the site name “Burned Mountain”). The trail that leads to “Serra Queimada” is also a crossing between the municipalities of Nova Friburgo and Macaé. Behuria lumiarensis occurs among small shrubs on steep slopes. It was collected with flowers and fruits in January.

Etimology: ―The epithet “ lumiarensis ” refers to the district of Lumiar, where the species was collected.

Conservation status: This species is known only from the type collection. The locality lies inside a partially protected area that allows private properties and small-scale agricultural activities, such as cattle raising on pastures, which leads to fragmentation of the natural vegetation. According to IUCN Standards and Petitions Subcommittee (2014) we used the criteria B1ab(ii) + B2ab(ii) based on geographic ranges: criterion B1 (EOO, Extent of Occurrence estimated to be less than 100 km ²) and criterion B2 (AOO, Area of Occupancy estimated to be less than 10 km ²). The values for Behuria lumiarensis were EOO = 0 km² and AOO = 4.000 km ², and by definition, is less than the threshold for classification as “critically endangered” (CR).

Discussion: ― Behuria lumiarensis can be distinguished from all other species in the genus by the combination of leaf blades with adaxial surface covered with sessile glands, abaxial surface moderately covered with stalked glands only on the veins, the hypanthium sparsely covered with stalked glands, long calyx tube, 1 × 4–5.5 mm, narrow sepals, 7–8 × 0.5 mm that are not apiculate in the apex, small petals, 10–12 × 4–6 mm, and glabrous ovary apex. This species is similar to three other ones (see table 1) from the state of Rio de Janeiro, among which it resembles most Behuria cordifolia (see details on the diagnosis above). Behuria lumiarensis differs from Behuria edmundoi Brade (1956: 221) by the smaller petals, 10–12 × 4–6 mm (vs. bigger petals, 13–14 × 6–6.5 mm in B. edmundoi ), longer and narrower sepals, 7–9 × 0.5 mm (vs. shorter and wider sepals, 5.5–6 × 0.8–1 mm), narrower calyx tube, 1 × 4–5.5 mm (vs. wider calyx tube, ca. 0.5 × 6 mm) and the glabrous ovary apex (vs. apex with stalked glands). It also differs from Behuria glazioviana Cogniaux (1891: 415) by the leaves with adaxial surface covered with sessile glands and abaxial surface sparsely covered with stalked glands only on the veins (vs. leaves with both adaxial and abaxial surfaces densely covered with stalked glands in B. glazioviana ), hypanthium sparsely covered with stalked glands (vs. densely covered with stalked glands), sepals not apiculate in the apex (vs. apiculate), larger petals, 14–18 × 7–11 mm (vs. 10–12 × 4–6 mm) and ovary apex covered by stalked glands (vs. glabrous apex).

Figures

FIGURE 1. Behuria lumiarensis.A) Branch with details of the petal apex and the stalked-glands on the abaxial leaf surface and petiole; B) Insertion of the petiole in the leaf blade, adaxial surface; C) Flower bud; D) Flower, lateral view; E) Antesepalous stamen; F) Antepetalous stamen; G) Hypanthium and ovary, longitudinal section; H) Immature capsule. (All from Bochorny et al. 200, UEC).

FIGURE 2. Behuria lumiarensis. A. Habit; B. Inflorescence with flower buds, flowers and immature fruits; C. Flower buds; D. Stamens with dorsal appendages and style; E. Flowers, lateral view; F. Vegetation of the “Macaé de Cima Environmental Protection Area”.