Rinorea guianensis Aubl.

  • Authority

    Hekking, W. H. A. 1988. violaceae Part l—Rinorea and Rinoreocarpus. Fl. Neotrop. Monogr. 46: i-ii, 1-208. (Published by NYBG Press)

  • Family

    Violaceae

  • Scientific Name

    Rinorea guianensis Aubl.

  • Type

    Type. French Guiana: s.l., s.d. (fl), Aublet s.n. (holotype, P (herb. Rousseau-Denaiffe 5: 169, illustrated in reverse in Aublet, 1775, t. 93); isotype, BM (type locality Caux (=Kaw) (fide Blake, 1924)).

  • Synonyms

    Conohoria rinorea A.St.-Hil., Alsodeia rinorea Spreng., Alsodeia floribunda Moric., Alsodeia castaneifolia Spreng.

  • Description

    Species Description - Tree or treelet 2-20 m tall. Branchlets appressed puberulous to strigulose when young, glabrescent when older. Leaves alternate; petioles 3-15 mm long, sparsely pilosulous when young, glabrescent when older; stipules deciduous, narrowly ovate to deltoid, acuminate, 2-13 x 1 mm, striate, pilosulous along the costa, margin ciliolate; lamina (narrowly) elliptic to obovate, acuminate to cuspidate, (3.5-)4.5-19 x (1-)2.5-9.25 cm; coriaceous to papery, glabrous on both sides; both sides of costa completely glabrous to strigulose near the base; lateral veins (8-)9-13(-16) pairs (acumen excluded); tertiary venation reticulate, sometimes varying to ± scalariform; base rounded to cuneate; margin (sub)serr(ul)ate, (sub)cren(ul)ate or subentire, mucronulate; acumen 0.5-1.5(-2.75) cm long, apex subobtuse to subacute, mucronulate. Inflorescences axillary, lateral and subterminal, solitary or often accompanied by one or two distinctly smaller inflorescences, thyrsoid, (3-)4-15.5 x 1.5-8 cm; central axis golden puberulous to hirtellous; cymules (1-)3-9 flowered, sometimes accompanied by 2-12 juvenile or undeveloped flowers; common peduncles 2-12.5 mm long, puberulous to hirtellous; ‘pedicels’ 1.5-7.5 mm long, articulate below the middle, puberulous to hirtellous; bracts and bractlets deciduous, ovate to deltoid, subobtuse to subacute, puberulous along the median part, ciliolate; bracts 0.5-1.5 x 0.5-1 mm; bractlets subopposite, 0.25-1.25 x 0.25-1 mm. Flower buds narrowly tolpoid, (sub)acute. Flowers drooping, creamy or yellowish-white, fragrant. Sepals subequal, ovate, (1-)1.5-2.75 x 1-1.75 mm, herbaceous, carnose near the base, appressed yellowish pilosulous along the median part outside and sometimes also inside, 1-5 veined, ciliolate, obtuse, mucronulate. Petals narrowly ovate, 3.5-5.5 x 1.25-1.75 mm, herbaceous, appressed yellowish pilosulous to glabrescent outside, appressed yellowish pilosulous near the apex inside, margin sometimes sparsely ciliolate, apex obtuse. Stamens 3-4.5(-5) mm long; filaments and dorsal glands fused to a tube, rarely one posterior filament free; filamental tube 0.2-0.75 mm high, carnose, appressed pilosulous to glabrous; dorsal glands sometimes differentiated, adnate to the filamental tube, deltoid, carnose, glabrous; anthers narrowly ovoid, 1-1.75 x 0.6-1 mm, apex obtuse, appendaged by 1-2 cusps, 0.1-1 x 0.1-0.2 mm; connective outside narrowly deltoid to ovate, acute to subobtuse, 0.75-1.75 x 0.25-0.75 mm, usually glabrous, rarely with 1-4 pilose hairs; connective scales lateral as well as apical, narrowly ovate to deltoid, 2.5-3.5(-4) x 0.75-1 mm, scarious, orange-brown, margin subentire near the base, apex subobtuse and suberose. Ovary subglobose, subconical or trapezoid, 0.75-2 x 0.5-1 mm, yellowish puberulous to strigulose; ovules one per placenta. Style filiform, erect or slightly sigmoid at the base, 2.5-3.5 mm long, exceeding the stamens by 0-0.5(-0.75) mm, pilosulous near the base; stigma truncate, obtuse. Capsule asymmetric, slightly oblique, ellipsoid, acuminate, subtended by subpersistent floral parts, coriaceous to subligneous, greenish when fresh, densely yellowish puberulous to strigillose; valves three, unequal, the larger one 7-10 x 4-5 mm, the two smaller ones 45 x 1.5-3 mm. Seeds one per valve, globose, ca. 2 mm in diam., glabrous, shining.

  • Discussion

    Rinorea guianensis is closely related to R. bahiensis and R. paniculata, less so to R. bicornuta. For remarks differentiating between the two latter species, see under those species. Rinorea guianensis differs from R. bahiensis mainly by: (1) sepals only 1-1.75 mm wide, versus 1.75-2 mm wide; (2) petals 2.5-3 x as long as wide, versus only 2-2.5 x; (3) anthers 1.5-2 x as long as wide, versus only 1-1.5 x; and (4) connective scales 34 x as long as wide, versus ca. 2.5 x.

    In general, floral parts of Rinorea guianensis are narrower and relatively longer than those of R. bahiensis. Floral parts such as peduncles, pedicels, bracts, bractlets, sepals and petals, are golden-whitish velutinous in R. bahiensis but in R. guianensis are less densely pilosulous to glabrescent. Inflorescences of R. bahiensis are more compact than those of R. guianensis. Leaves of R. bahiensis are usually more elliptic than those of R. guianensis and often also smaller.

    Typical specimens of Rinorea guianensis can be easily distinguished by these differentia, but in SE Brazil there occur specimens of R. guianensis with flowers tending to those of R. bahiensis and in turn there occur specimens of R. bahiensis in French Guiana with leaf characters of R. guianensis and R. paniculata. In such specimens introgressive hybridization is not excluded.

    Even within Rinorea guianensis itself there occur three different kinds of local races: (1) specimens with (sub)entire leaves and tertiary venation ± scalariform just as in R. paniculata, occurring in Amazonia (a) and in the Coastal Cordillera of Venezuela (c); (2) specimens with subserrate to subcrenate, rarely subentire leaves and tertiary venation reticulate; predominantly in Amazonia and adjacent French Guiana (a); and (3) specimens with distinctly crenulate or serrulate leaves and tertiary venation densely reticulate; predominantly in SE Brazil (b).

    Distribution and Ecology: Probably flowering and fruiting throughout the year. Its main area of distribution is Amazonia (Brazil, Peru) and adjacent French Guiana, but it is found also in two disjunct areas: (a) SE Brazil with the forest refugia Pernambuco, Bahía, Rio de Janeiro and the area between Rio de Janeiro and Brasilia-Araguia; and (b) the Coastal Cordillera of Venezuela including the forest refuge Rancho Grande. The disjunction in SE Brazil, isolated from its main center of distribution, was probably caused by a climatic change from a warmer humid climate to a cooler and dryer type since the early Tertiary (van der Hammen, 1974), by which process a formerly coherent area of tropical rain forest became fragmented. Human influences also caused the areas of the SE Brazilian rain forests to become still more limited. The next disjunctum, mainly on the northern slopes of the Coastal Cordillera in Venezuela, is probably due to the same climatic change over the whole continent, combined with the gradual uplift of this Cordillera since the Pliocene. This resulted in an additional rain shadow S of this Cordillera. In the meantime Rinorea guianensis could survive on the northern slopes of the rising Cordillera, which was catching still more rain, so that the humid tropical rain forest habitat was maintained. This species occurs as undergrowth in primary, secondary and disturbed rain forests, from 0 to 425 m; it inhabits uninundated as well as periodically inundated areas. It is often collected along rivers and creeks, in sandy to clayish soil.

  • Common Names

    Rinoré, Ajará, Amarelinho, Aquariquara(na), Can(n)elha de Jacamín, Cinzeiro, Imbiribatan, Pau de Gamba

  • Distribution

    Venezuela South America| Miranda Venezuela South America| Peru South America| Loreto Peru South America| Brazil South America| Amapá Brazil South America| Pará Brazil South America| Amazonas Brazil South America| Bahia Brazil South America| Mato Grosso Brazil South America| Minas Gerais Brazil South America| Pará Brazil South America| Pernambuco Brazil South America| Rio de Janeiro Brazil South America| Rondônia Brazil South America| Bahia Brazil South America|