Lavoisiera nervulosa Naudin (1844: 149)

Martins, Angela B. & Almeda, Frank, 2017, A Monograph of the Brazilian endemic genus Lavoisiera (Melastomataceae: Microlicieae), Phytotaxa 315 (1), pp. 448-450 : 448-450

27. Lavoisiera nervulosa Naudin (1844: 149) . Type:— BRAZIL. Bahia: “In provincia Bahiensi, Igreja Velha, Serra da Jacobina ,” J. Blanchet 3333 (holotype: G!; isotypes: B, destroyed, BM!, BR-3!, C!, F-2!, G-2!, K!, LE!, MO!, NY!, P!, US-2!, W-2!, photos of B isotype: F!, NY!).

Erect, laxly to densely branched subshrubs 0.6–1 m or shrubs to small trees 2–3 m tall, viscous, the young branches, leaves, hypanthium and calyx lobes sparsely to moderately covered with somewhat spreading glandular trichomes up to 1 mm long that are sometimes inconspicuous and early caducous. Branches and branchlets rounded to subquadrangular, furrowed longitudinally on opposite faces, defoliating basally, more or less glabrescent with age; internodes 3–10 mm long, with knobby thickenings that persist where a leaf has fallen away; nodes with inconspicuous semi-orbicular leaf scars and short glandular trichomes (not always visible and conspicuous). Leaves sessile, semi-amplexicaul, spreading to somewhat imbricate at the ends of branchlets; blade (20–)30–45 × (8–) 10–15 mm, chartaceous, oblong-lanceolate to oblong-elliptic, base rounded or inconspicuously subauriculate, apex acute (sometimes bluntly so) to rounded, margin subcallose, subserrulate and glandular-ciliolate (the cilia 1–1.5 mm long), occasionally entire or obscurely glandular-ciliolate and slightly revolute, adaxial surface with subappressed trichomes, abaxial surface somewhat viscid, especially on juvenile leaves, the

LAVOISIERA ( MELASTOMATACEAE )

Phytotaxa 315 (1) © 2017 Magnolia Press • 133 erect trichomes 0.5–1 mm long and typically distributed along the veins, reticulation conspicuous, frequently intermixed with a sparse cover of sessile glands on both surfaces, flat, green to yellowish-green, 6–11(–14)-nerved, only the midvein and the inframarginal pair extending to the apex. Flowers typically 6-merous, sometimes 7–8- merous, solitary on pedicels 3 mm long, terminal, but commonly overtopped by lateral branches. Bracts subtending the flowers 4–6, subsessile, petioles 1–3 mm long, blade 20–25 × 15 mm, ovate-lanceolate, base rounded to subcordate, membranaceous, glandular-puberulous on both surfaces, margins glandular-ciliate. Hypanthium (at anthesis) 10–12 mm long, 4 mm wide basally and ca. 7 mm wide distally below the calyx, urceolate and strongly constricted at the ovary apex, moderately to densely covered with smooth glandular trichomes. Calyx tube 2–3 mm long; calyx lobes (at anthesis) ca. 3 mm long, 2–3 mm wide basally between sinuses and 1–1.5 mm wide distally, persistent, triangular, acute at the apex tapering to a sometimes caducous 1 mm long gland-tipped trichome, glandular-puberulous on both surfaces, margins glandular-ciliate. Petals 20–23 × 10–12 mm, reportedly yellow with an asymmetrical red marking on one side of the petal abaxially, rarely lavender to pink, obovate, apex rounded to obtuse, base attenuate, margins eciliate. Stamens 12 (sometimes 14 or 16), dimorphic, yellow throughout: large (antesepalous) stamens 6(–7–8), filaments 11 mm long, anther thecae 6 × 1 mm, oblong, rostrum 0.5–1 mm long, pedoconnective 8–9 mm long, appendage 2.5–3 mm long, bilobed; small (antepetalous) stamens 6(–7–8), filaments 7–8 mm long, anther thecae 5 × 1.2 mm, oblong, rostrum 0.5 mm long, pedoconnective 3–4 mm long, appendage ca. 1 mm, bilobed. Ovary 6–7-locular, completely inferior, style 13–15 mm long, curved, yellow, stigma punctiform. Fruiting hypanthium (including calyx lobes) 15 × 4–5 mm, sessile to semi-sessile, conspicuously constricted and prolonged above the ovary. Capsule (at maturity) 8–12 mm long, enveloped by the persistent hypanthium and calyx lobes, dehiscing from the base to the apex. Seeds 0.71–1.15 × 0.37–0.50 mm, oblong to reniform, yellowish-brown, periclinal cell walls of the testa concave (foveolate), the raphal zone about 50% the length of the seed. Chromosome number unknown.

Illustration:— Figure 50 .

Photographic images:— Figures 11A, B .

Phenology:—Flowering sporadically all year; fruiting collections have been made in February, June, July, and December.

Distribution and habitat:—Largely centered in Bahia on the Chapada Diamantina (municípios of Andaraí, Morro do Chapéu, Mucugê, and Jacobina). It typically grows in damp sites in campo rupestre, alluvial sandy areas, and riverside vegetation at 900–1200 m. Figure 22 .

Conservation status:—This species is restricted to the Chapada Diamantina and vicinity and Serra da Jacobina in Bahia. A majority of the known collections come from the município of Mucugê but only two populations appear to be afforded some protection within Parque Nacional Chapada Diamantina . The EOO is 19 km ² and the AOO is 12 km ². The area does not appear to be suffering from expanding urban populations but fires do create periodic threats. In view of its limited EOO and AOO we recommend a classification of Critically Endangered (CR): B1ab(iii).

Discussion:—The most distinctive features of L. nervulosa include its spreading glandular trichomes (to 1 mm long) on young branches, leaves, hypanthia, and calyx lobes, subauriculate leaf bases, markedly constricted hypanthia at the ovary apex that creates a cup-like vessel with flaring calyx tube and persistent lobes, and uniformly pink/lavender or yellow petals with asymmetrical reddish markings or flushing on the abaxial surface.

For a species with a comparatively limited geographic distribution L. nervulosa exhibits notable variation. The population centered in the Mucugê region consists of plants 2–3 m tall with yellow petals that are sometimes flushed with red on the abaxial surface and in bud, and oblong-lanceolate leaves that are glabrate with laxly reticulate venation abaxially and an acute apex. The type specimens and those from the Morro do Chapéu population are 0.6–1 m tall (based on five collections), with pink/lavender petals, and oblong-elliptic leaves with more pronounced reticulate venation abaxially, and a distinctly rounded apex.

Three collections from Goiás have foliar morphology, overall indumentum, and 6-locular ovaries that are like typical Lavoisiera nervulosa . Glaziou 21307 (BR-2!, C!, G!, P!) from Morro do Abbade and Glaziou 21308 (BR- 2!, C!, F, G!, K!, LE!, P!, R) from Serra do Arruda, both of which were collected near Pico dos Pireneus over 100 years ago, are only in mature fruit so it has not been possible to identify them with certainty. They differ from typical L. nervulosa by their thick semi-woody capsules with a conic apex, glabrous hypanthia, and deciduous calyx lobes. Another collection, Glaziou 21309 (BR-2!, C!, F!, G!, K!, LE!, P!) from Goiás (Fazenda Boa Vista), is also reminiscent of L. nervulosa but its leaf blades are coarsely serrulate, glabrous with more pronounced reticulate

134 • Phytotaxa 315 (1) © 2017 Magnolia Press

MARTINS & ALMEDA venation abaxially, and its capsules are also woody and enveloped by a glabrous hypanthium that has caducous calyx lobes. Flowering material of these populations is needed for comparison with the distinctive and unmistakable hypanthia, calyx tube and calyx lobes of typical L. nervulosa .

LAVOISIERA ( MELASTOMATACEAE )

Phytotaxa 315 (1) © 2017 Magnolia Press • 135

The only species with which L. nervulosa might be confused are L. glandulifera and L. harleyi . The former, a Minas Gerais endemic, is readily separated by its pink (rarely uniformly pale yellow) 5-merous flowers, 5-locular ovary, and spreading glandular trichomes on the foliar surface that are surrounded at the base by minute sessile glands ( Figure 38B ). Lavoisiera harleyi , which is also endemic to Bahia but allopatric with L. nervulosa , has 6- merous flowers and a 6-locular ovary but it has dark pink to pink-magenta petals with a yellow base, hypanthia that are glabrous distally just below the torus on the outer surface, and spreading glandular trichomes on the abaxial foliar surface that are surrounded at the base by minute sessile glands.

Additional specimens examined:— BAHIA: Mpio. Morro do Chapéu , 11°35'S, 41°13'W, Bautista 395 ( K!, R!, RB!) ; without exact locality, Blanchet 214 ( W!) ; a 6 km N de Mucugê , estrada Mucugê-Andaraí, Cerati et al. 331 ( CAS!, CEPEC, SP!, SPF) ; Mpio. Mucugê , Furlan et al . CFCR 442 ( CAS!, K!, SPF!) ; Mpio. Mucugê , Alto do Morro do Pina. Estrada de Mucugê a Guiné, a 25 km N of Mucugê, Giulietti et al . CFCR 1553 ( CAS!, SPF!, UEC!) ; Mpio. Mucugê , ca. 2–3 km SW of Mucugê on the road to Cascavel, 13°1'S, 41°24'W, Harley 18788 ( CEPEC!, K!, NY!, US!) ; Mpio. Mucugê , Serra do Sincorá, 3 km SW of Mucugê on the Cascavel road, 13°1'S, 41°24'W, Harley 21040 ( CEPEC!, NY!, RB!, US!) ; Mpio. Mucugê, Córrego Moreira, Hatschbach 47520 ( CEPEC!, MBM!, US!) ; Mpio. Mucugê , arredores de Mucugê, Hatschbach & Kummrow 47915 ( BR!, CAS!, F!, MICH!, NY!, US!) ; Mpio. Mucugê , ca. 7 km N of Mucugê on road to Andaraí, Kral et al. 72889 ( CEPEC!, SP!) ; Mpio. Morro do Chapéu , Morro da torre de televisão, Martinelli et al. 5231 ( RB!) ; Mpio. Andaraí, Serra de Andaraí , Capa-bode, estrada para Mucugê , Martinelli et al. 5435 ( RB!) ; Mpio. Mucugê , margem da Estrada Mucugê-Cascavel, Km 3 a 6, próximo ao Rio Paraguaçu, Menezes et al . CFCR 1442 ( CAS!, UEC!) ; Mpio. Mucugê, ca. 3 km S de Mucugê , na estrada para Jussiape, Mori & Benton 13167 ( CEPEC!, NY!, US!) ; Mpio. Morro do Chapéu , Telebahia Tower, ca. 6 km S of Morro do Chapéu, Mori & Boom 14441 ( CEPEC!, NY!, RB!, US!) ; Mpio. Mucugê , ca. 3 km S de Mucugê, na estrada para Jussiape, 13°S, 41°24'W, Mori et al. 12551 ( CEPEC!, UEC!, US!) ; Mpio. Morro do Chapéu , Utinga, ca. 5 km do Morro do Chapéu, Wanderley et al. s.n. ( CAS!) .

Figures

FIGURE 11. SEM images of seeds for representative Lavoisiera species showing lateral symmetrical plane (left) and detail of testa cells and cell wall microrelief (right). A–B. L. nervulosa (Mori & Benton 13167). C–D. L. pulchella (Rossi & Catharino 1540). E–F. L. pulchella (Reitz & Klein 17495). Scale bars: A & C=300 µm; B=75 µm; D=30 µm; E=380 µm; F=38 µm.

FIGURE 22. Distributions of Lavoisiera arachnoidea, L. confertiflora, L. daviesiana, L. harleyi, L. mellobarretoi, L. nervulosa, and L. rundeliana.

FIGURE 38. Lavoisiera glandulifera. A. Habit. B. Adaxial leaf surface with enlarged surface detail (lower right). C. Flower. D. Hypanthium and calyx lobes. E. Ovary cross-section. F. Petal. G. Ventral view of antesepalous stamen. H. Ventral view of antepetalous stamen. I. Seed. (Based on: A–I, Almeda et al. 8592, CAS, UEC.)

FIGURE 50. Lavoisiera nervulosa. A. Habit. B. Abaxial leaf surface (from young branch) with enlargement of surface detail (upper right). C. Abaxial bract surface. D. Flower. E. Hypanthium and calyx lobes. F. Ovary cross-section. G. Petal. H. Ventral view of antesepalous stamen. I. Ventral view of antepetalous stamen. J. Seed. (Based on: A–J, Giulietti et al. CFCR 1553, CAS, UEC.)