Behuria mestrealvarensis D.T.Iglesias & R.Goldenb., 2016

Iglesias, Diego Tavares, Dutra, Valquíria Ferreira & Goldenberg, Renato, 2016, Behuria mestrealvarensis (Melastomataceae): a new species on an inselberg in Espírito Santo, Brazil, Phytotaxa 255 (3), pp. 281-286 : 281-285

Behuria mestrealvarensis D.T.Iglesias & R.Goldenb. sp.nov. ( Figures 1–3 )

Type:― BRAZIL. Espírito Santo: Serra, Área de Proteção Ambiental Mestre Álvaro , trilha principal, escadaria no topo, 20º 10’ 13” S, 40º 18’ 51” W, 15 January 2014 (fl., fr.), D. T. Iglesias, P. H. D. Barros & A. D. Firmino 169 (holotype: VIES!; isotypes: MBML!, NY!, RB!, UPCB!) .

Behuria mestrealvarensis is apparently similar to B. capixaba , from which it differs by the glabrous petioles and hypanthia, by the solitary flowers or these in simple or compound triads up to 7 flowers, elliptic bracteoles almost the same size of the pedicel and hypanthium, sepals with eciliate margins and ovary apex with trichomes up to 0.5 mm.

Shrubs 0.6–1 m tall, glabrous. Young branches terete and striate when dry, older ones nodose. Leaves opposite; petioles 3–8 mm long; blades 1.8–4.6 × 1.1–2.3 cm, oval or elliptic, apex acute or acuminate, base obtuse or decurrent, margins serrulate, not ciliate, plane, chartaceous, slightly discolorous in dried specimens, longitudinal nerves three, sometimes with an additional faint submarginal pair, acrodromous, basal, main veins impressed adaxially and raised abaxially, their bases joined by a very short membrane (domatia) on the abaxial surface, transverse veins and reticulation barely visible on both surfaces. Flowers isolate or in frondose dichasia, and sometimes in compound dichasia (with up to 7 flowers), apical; bracts two, persistent, leafy, sessile or with a short petiole up to 2 mm long, blades 10–15 × 5–9 mm, elliptic to broadly elliptic, base acute to decurrent, apex acute to acuminate, margins serrulate; bracteoles two, persistent, leafy, 5–8 × 2–4 mm, elliptic, base decurrent, apex acute, margins entire or serrulate, glabrous. Flowers (5–)6-merous, pedicels 1.5–2 mm long. Hypanthium 4–5 × ca. 3.5 mm, campanulate, green or green with pinkish spots, glabrous, torus glabrous. Calyx persistent, adaxial and abaxial surfaces pink; tube ca. 1 mm long, glabrous; sepals 3.5–4.5 mm long, triangular to hemi-elliptic, margins serrulate-ciliolate (the cilia sometimes caducous), glabrous; external teeth absent. Petals 12–13 × 6–8 mm, obovate and asymmetric, the left margin (in adaxial view) pink, entire, and thick, right margin (in adaxial view), white to pinkish, undulate, and thin, apex rounded, adaxial surface glabrous, abaxial surface subapically and submarginally covered with glandular trichomes 0.5–1mm long, otherwise glabrous. Stamens 10–12, subisomorphic, glabrous; filaments 6–7 mm long (antesepalous) or 5–6 mm long (antepetalous), white, strongly flattened; connective yellow, not prolonged below the thecae, dorsal appendages ca. 1.5 mm long, yellow, linear-subulate; anthers 4.5–5 mm longin both cycles, yellow, oblong-linear, apex acute, the thecae prolonged up to 0.3 mm below the insertion of the filament, with a single, apical (but slightly ventrally inclined) pore. Ovary 2.5–3.5 mm long, ca. 1/3 to 1/2 basally adhered to the hypanthium, 4-locular, apex with few glandular trichomes ca. 0.5 mm long; style 8.5–12 mm long, slightly curved or sigmoidal, glabrous. Capsules 6–8 × 4–6 mm, the carpels exceeding the hypanthium length by ca. 1mm; seeds ca. 1.5 × 0.5 mm, elongate or oblong, raphe almost equaling the seed length, testa granulate.

Distribution and ecology:— Behuria mestrealvarensis has been collected only on the top of an isolated inselberg ( Figure 3 ), at 800–833 m elev. As in similar environments, the place is frequently covered with mist or clouds, and the soil in is very thin. The inselberg is surrounded by montane rain forest (“Floresta Ombrófila Densa Montana ”, according to the official Brazilian vegetation classification system, Veloso et al. 1991), but have a particular vegetation on its top, consisting mostly of herbs and shrubs up to 1m tall. According to Iglesias et al. (2014) the following species are common in the area: Barbacenia spectabilis L.B. Smith & Ayensu (1976: 17) , Vellozia variegata Goethart & Henrard ( Henrard 1937: 381), Tibouchina radula Markgraf (1927: 49) , Epidendrum secundum Jacquin (1760: 29) , Cyperus hermaphroditus ( Jacquin 1791: 174) Standley (1916: 88) , Achetaria azurea ( Linden 1862: 6) V.C.Souza ( Souza & Giulietti 2009: 90) and Axonopus graniticola P.L.Viana ( Viana & de Paula 2013: 9). This species was collected with flowers from November to February, with fruits in January and February.

Etymology:—“Mestre Álvaro” is the name of the isolated, 833 m elev. inselberg where all specimens of B. mestrealvarensis have been collected. From its location in the municipality of Serra, it dominates the landscape of Vitória, the capital of Espírito Santo, and neighboring areas to the north. It is said that the weather in the region depends on Mestre Álvaro’s “hat”, i.e. the clouds that typically cover its top are believed to indicate incoming rain. A very good description of this locality was made by Saint-Hilaire (1833; 1936). He climbed the mountain, then known as “Mestre Alvo”, in 1818, but curiously did not collect plants in this trip and hence missed this Behuria .

Conservation status:―This species is known from only one locality. This is inside a partially protected area (“Área de Proteção Ambiental Mestre Álvaro”), managed by the State of Espírito Santo. This kind of protected area allows private properties and small-scale agricultural activities, such as cattle raising on pastures, which leads to fragmentation of the natural vegetation. Moreover, the area is naturally isolated, close (and partially surrounded) by urban areas, and the species’ area of occupancy is very restricted (ca. 0.2 km 2). Based on IUCN criteria ( IUCN 2001, 2011), this species must be assigned as Critically Endangered (CR).

Paratypes:― BRAZIL. Espírito Santo: Serra, Mestre Álvaro , 21 November 1982, J. R. Pirani, O. Yano & D. P. Santos 170 ( SP!, SPF!) ; 11 November 1990, P. C. Vinha 1166 ( VIES!) ; 24 February 2013, D. T. Iglesias & W. C. Cardoso 98 ( VIES!) ; 15 January 2014, D. T. Iglesias , P. H. D. Barros & A. D. Firmino 170 ( VIES!) .

Discussion:― Behuria mestrealvarensis differs from the other species in the genus (except B. capixaba Goldenberg & Reginato 2009: 293 ) by the chartaceous leaves with 3 nerves (plus a faint, submarginal pair) and a membrane domatia, hypanthium with a glabrous torus and glandular-pubescent petals (the characters listed here are the ones analyzed by Goldenberg & Reginato 2009). The species most similar to B. mestrealvarensis is B. capixaba , collected about 100–120 km to the north, in the municipalities of Marilândia and Governador Lindenberg, both in Espírito Santo. Behuria capixaba differs from the former due to the short glandular trichomes found almost all over the plant, mostly on petioles and hypanthia (vs. glabrous petioles and hypanthia in B. mestrealvarensis ), and the cymose inflorescences, with 3–30 flowers without a dichasial organization (vs. solitary flowers or simple or compound triads up to 7 flowers), linear-lanceolate bracteoles that are much shorter than the pedicel + hypanthium (vs. elliptic bracteoles almost the same size of the pedicel + hypanthium), sepals with glandular-ciliate margins (vs. with eciliate margins), and ovary apex covered with trichomes 1.4–2.5 mm long (vs. trichomes up to 0.5 mm).

Figures

FIGURE 1. Behuria mestrealvarensis. A. Flowering branch. B. Leaf, abaxial surface, with details of the margin and base. C. Flower bud with bracteoles. D. Flower, longitudinal section. E. Antesepalous stamen. F.Antepetalous stamen. G. Immature capsule (all from Iglesias et al. 169, UPCB).

FIGURE 2. Behuria mestrealvarensis. A. Vegetation on Mestre Álvaro, where the plants have been found. B. Plant with flowers. C. Flower buds. D. Flower, frontal view. E. Dichasium in lateral view. F. Immature capsule.

FIGURE 3. Distribution map of Behuria mestrealvarensis.