Standleya glomerulata J.G.Jardim

Jardim, Jomar Gomes & COSTA, CRISTINA BESTETTI, 2015, A new species of Standleya (Rubiaceae, Coussareeae) with a new record for Bahia, Brazil, Phytotaxa 206 (1), pp. 74-78 : 75-77

Standleya glomerulata J.G.Jardim & C.B.Costa, sp. nov. ( Figures 1 , 2 ).

Type:— BRAZIL. Bahia: Mun. Rui Barbosa, Serra do Orobó , caminho para o Pátio das Orquídeas, floresta estacional semidecidual, 12 o 18’10’’S, 40 o 29’ 14’’W, 550 m, 20 August 2005, fl., fr., L. P. de Queiroz et al. 10835 (Holotype: HUEFS!; Isotypes: CEPEC!, K!, MBM!, NY not seen, RB!, SP!) .

Diagnosis:— Ab omnibus ceteris speciebus generis Standleyae inflorescentia dense glomerulata pluriflora sessili, calycis lobis 2, inaequalibus, lanceolatis vel lineari-lanceolatis distincta.

Herbs with prostrate and creeping stems, to 20–30 cm, perennial. Stems 1–1.5 mm diam., densely tomentose, hairs soft whitish; internodes short, 2–6(–8) cm. Stipules interpetiolar, 2 at each node, connate at the bases, narrowly triangular, unilaciniate, lobes 3.5–5 mm, persistent, densely tomentose, crowned by one colleter-tipped awn and two colleters in the middle of each side of the lobe, sheath ca. 1 mm, tomentose, with a group of 4–6 additional small colleters inside the sheath, the latter 0.4–0.6 mm, triangular-setaceous, dark-brown. Leaves petiolate to subsessile, petioles 0.3–0.7 cm, tomentose, blades 1.8–3.8 × 0.6–1.5 cm, lanceolate to ovate-lanceolate, membranaceous, slightly discolorous, base cuneate or, less commonly, broadly rounded, apex acute, margins tomentose, velutinous to tomentose; venetation brochidodromous, secondary veins 4(–5) per side. Inflorescences glomerulate cymose, globose, terminal to pseudoaxillary, with the secondary development of the branches, sessile, densely tomentose, 15–20-flowered, bracts foliaceous 1.5–3.2 × 0.5–1.3 cm, ovate-lanceolate, bracteoles 0.8–0.12 × 0.2–0.3 cm, linear-lanceolate to lanceolate, tomentose on both sides. Flowers 4-merous, presumably distylous, sessile, buds clavate, with an obtuse apex; hypanthium turbinate, 2–2,5 mm, tomentose, calyx lobes 2, unequal, linear-lanceolate to lanceolate, erect, apex acute, the bigger ones 4–6 × 1–2 mm, the smaller 2–4 × 0.3–0.5 mm, tomentose on both sides, with 2 colleters in the sinuses between the lobes; corolla infundibuliform, 4–6 mm, tube 1.5–3 mm, pubescent externally, especially in the upper part of the lobes, internally with a moniliform hair band in the middle of the tube, tube and throat whitish, lobes 1.5–2.5 mm, lilac, lanceolate, valvate in bud; disk 2-lobed; stamens 4, included in the upper half of the corolla tube, 1.5 mm, filaments 1 mm, anthers dorsifixed, 0.5 mm, oblong-elliptic, style included, 0.5–3 mm; stigma bifid, 1.5–2.5 mm, ovary 2-locular, ovules on a short and centrally inserted linear placenta attached to the middle of the septum, placenta 1–1.5 mm, ovules 7–8 in each locule. Fruit septicidal capsular, coriaceous, obovoid to conic, laterally compressed, 4–5 × 3–4 mm at maturity, pubescent, sessile, pale brown when mature, crowned by 2 persistent and unequal calyx lobes and a nectar disc. Seeds more than 10 per fruit, orbicular, subangular or plano-convex, 0.5–0.6 mm diam., seed coat granulate, pale to dark brown; embryo 0.3–0.4 mm, linear, cotyledons ovate.

Additional specimens examined (paratypes):— BRAZIL. Bahia: Andaraí, Chapada Diamantina , 12°54’S, 41 o 14’’ W, 30 April 2001, fl, D. L. Santana, L. J. Alves & M. L. Guedes 188 ( ALCB) ; Lençóis, estrada para a cidade, 12°33’19’’S, 40 o 21’52’’W, 460 m, 02 February 2009, fl, fr, D. Cardoso N. P. Smith & C. O. Azevedo 2398 ( HUEFS) ; estrada para o povoado de Remanço, Parque Nacional da Chapada Diamantina , 12°32’32’’S, 40 o 21’41’’W, 12 November 2012, fl, fr, J. A. Oliveira, R. C. Forzza & R. F. Monteiro, E. L. Assis , L. Daneu 236 ( RB, CEPEC) ; Rui Barbosa, Serra do Orobó, caminho para o Pátio das Orquídeas , 12°18’10’’S, 40 o 29’14’’W, floresta estacional semidecidual, 550 m, 18 September 2005, fl, fr, D. Cardoso 764 ( HUEFS, K, RB) ; ib., ARIE da Serra do Orobó, Riacho do Meio , 12 o 18’33’’S, 40 o 29’22’’W, 560 m, 26 July 2004, fl, fr, L. P. de Queiroz J. G. Carvalho Sobrinho, D. Cardoso & T. Costa 9261 ( HUEFS, CEPEC, JPB) ; 16 November 2006, fl, L. P. de Queiroz & D. Cardoso 12001 ( HUEFS) .

Etymology. The specific epithet refers to the densely glomerulate inflorescence.

Distribution and ecology. This species is known only from very small populations within forest fragments after intense human action, at altitudes of 550–600 m, of the relict seasonally-dry forests on Orobó Mountain and “Chapada Diamantina ”, Bahia, Brazil. This is the first record of the genus for Bahia. Specimens in the flowering/early-fruiting stage have been observed in February, April, July, September, and November.

Conservation. Endangered (EN), B1 a, b(i,ii,iii, iv). Area of occupancy estimated at <5000 km ². This new species was found in four areas, with only two of them protected, the ARIE (Area of Relevant Ecological Interest) of the Serra do Orobó, and the Chapada Diamantina National Park.

Taxonomy. Standleya glomerulata differs from other Standleya species notably by its densely-glomerulate multiflowered sessile inflorescences, and by the two linear-lanceolate to lanceolate and unequal calyx lobes. Bradea had been separated from Standleya for having only two calyx lobes (vs. four in Standleya ), and its orbicular and winged seeds (vs. suborbicular, unwinged, plano-convex and granular seeds in Standleya ). Additionally, the habit of Standleya is that of prostrate herbs with erect branches, while that of Bradea is shrubby ( Brade 1932, 1949). Although in most species of Bradea the calyx is 2-lobed, in B. anomala Brade (1949:16) and B.bicornuta Brade (1949:15) it may be 2–3-lobed. In all known species of Bradea seeds are winged and orbicular, whereas in Standleya they are unwinged. Some of the characters differentiating the two genera are presented in Table 1.

Figures

FIGURE 1. Standleya glomerulata. A. Habit. B–C. Leaves, dorsal and ventral view respectively. D. Stipule with colleters, ventral view. E. Stipule in bud with colleters, trichomes removed. F. Corolla. G. Flower and ovary, in longitudinal section. H. Immature fruit and bract, detached from the infructescence. (Drawn from the holotype, except for the habit (A–C), drawn from Queiroz et al. 9261).

FIGURE 2. Standleya glomerulata. A. Habit. B. Inflorescence with flowers at anthesis, frontal view (photo A, by R. Monteiro; B, by D. Cardoso).