A New Species of Palicourea (Rubiaceae, Psychotrieae) from Southern Brazil

Abstract

The new species Palicourea australis C. M. Taylor is described and illustrated. This new species is distinguished from R marcgravii A. St.Hilaire by its shorter corollas with dense external pubescence that is confined to the tube and corolla lobes with appendages or pronounced thickenings. During study of Brazilian Palicourea Aublet for the Phanerogamic Flora of Sao Paulo State project, the following well-marked species was discovered to be undescribed, due largely to confusion in the identities of previously described species. As circumscribed by Taylor (1997), Palicourea is distinguished within the Rubiaceae by its persistent stipules that are united around the stems into a continuous sheath and bilobed in the interpetiolar portion; generally colored inflorescences with the flowers usually pedicellate; corollas that are usually brightly colored, usually five-lobed, and have welldeveloped tubes that are somewhat swollen at the base and glabrous internally except for a dense ring of pubescence situated just above this basal swelling; and drupaceous fruits with usually two pyrenes. This Neotropical genus includes about 200 species found from sea level to high montane regions. The species are typically distylous and apparently pollinated by hummingbirds. Palicourea australis C. M. Taylor, sp. nov. TYPE: Brazil. Parani: Mpio. Mangueirinha, Cachoeira, 6 Dec. 1989, G. Hatschbach & V Nicolack 53679 (holotype, MBM; isotype, MO4224516). Figure 1. Haec species a Palicourea marcgravii corollae tubo extus velutino-pubescente et lobulis incrassationes projecturasve abaxiales gerentibus distinguitur. Flowering 0.7 m tall, to 2 m tall; stems terete, glabrous to puberulous. Leaves paired; blades elliptic to narrowly so, 6-17 x 2-6.5 cm, at apex acute to somewhat acuminate, at base acute to cuneate, papyraceous, adaxially and abaxially glabrous to minutely puberulous, often more densely so along costa; secondary veins 6 to 10 pairs, extending to near margins but not uniting with them, with 1(to 3) weak to well-developed intersecondary veins usually present between pairs of secondary veins, adaxially costa prominulous and remaining venation plane to a little thickened, abaxially costa prominulous to prominent, secondary veins prominulous, and reticulated minor venation sparse, plane to thickened; margins thinly to distinctly cartilaginous, minutely ciliolate; petioles 3-7 mm long, glabrous to puberulous; stipules puberulous to glabrescent, persistent at least with the leaves, united around the stem into a continuous truncate sheath 0.2-1 mm long, lobes narrowly triangular to somewhat lanceolate, 3-7 mm long, acute to acuminate or bidentate. Inflorescences terminal, erect, with peduncles 3.5-11.5 cm long; panicles shortly pyramidal to somewhat corymbiform, 2.5-8.5 x 3-6 cm excluding corollas, with 4 to 6 pairs of developed secondary axes, these often subopposite to alternate, with flowers pedicellate in cymules of 3 to 7; bracts entire to ciliolate, those subtending secondary axes triangular, 0.5-6 mm long, acute, those subtending pedicels deltoid to narrowly triangular, 0.3-1 mm long, acute; pedicels 1-4 mm long; peduncle, axes, bracts, and pedicels puberulous to glabrescent, red;flowers distylous, with hypanthium cylindrical to turbinate, ca. 1 mm long, glabrous to puberulous; calyx limb puberulous to usually glabrous, divided nearly to base, lobes ovate to deltoid or shortly trilobed, 0.8-1.1 mm long, acute to cuspidate, entire to laciniate; corolla tubular, yellow on tube and pink to purple on lobes, a little swollen at base, generally straight at base and in tube, externally densely pubescent on tube with stout trichomes 0.3-1 mm long, glabrous on lobes, internally glabrous except for a sparsely pilosulous ring ca. 1 mm wide at ca. 2 mm above base, tube 8-11 X ca. 2.5-4 mm, lobes triangular, 1.5-2 mm long, acute, thickened and shortly involute adaxially at apex, abaxially with a thickened and rounded appendage to 0.5 mm long; anthers in short-styled form ca. 4 mm long and partially exserted, in longstyled form ca. 3 mm long and positioned ca. 2/3 of length of corolla tube above base; stigmas in shortstyled form ca. 2 mm long and positioned ca. 2/3 of length of corolla tube above base, in long-styled form ca. 1 mm long and exserted; disk ca. 1-1.2 NovoN 10: 161-163. 2000. This content downloaded from 157.55.39.255 on Tue, 24 May 2016 05:29:34 UTC All use subject to http://about.jstor.org/terms