A remarkable new species of Ormosia (Leguminosae: Papilionoideae: Sophoreae) from Bahian Atlantic Rain Forest, Brazil
- First Online:
- Cite this article as:
- Cardoso, D.B.O.S., Meireles, J.E. & de Lima, H. Brittonia (2009) 61: 22. doi:10.1007/s12228-008-9051-y
- 79 Views
Ormosia timboënsis is described and illustrated as a new species based on fruit and leaf material collected in a fragment of Atlantic Rain Forest in central Bahia State, Brazil. This new species can be recognized by possessing the largest seed and hilum of those that have been reported in Ormosia. In addition, O. timboënsis has leaves that in combination with the fruit characters do not match any species currently described in the genus.
Key WordsAtlantic rain forestBahiaLeguminosaeOrmosiaSophoreae
Ormosia timboënsis é descrita e ilustrada como nova espécie baseada apenas em material com folha e fruto coletado em um fragmento de Floresta Atlântica ombrófila na região central da Bahia, Brasil. Esta nova espécie pode ser diferenciada por possuir semente e hilo dentre os maiores já vistos em Ormosia. Além disso, O. timboënsis apresenta folhas que em combinação com os caracteres do fruto não permitem acomodá-la em nenhuma das espécies atualmente descritas no gênero.
Ormosia Jacks. comprises ca. 130 species of predominantly tropical papilionoid legume trees, about 80 of which occur in the neotropics and with the rest in eastern Asia to northeastern Australia (Rudd, 1965; Polhill, 1981; Pennington et al., 2005). Within the Neotropics, the genus reaches its greatest diversity in Brazil with approximately 40 species, the bulk of which occur in the Amazon region (Ducke, 1939; Rudd, 1965). Ormosia is traditionally assigned to the tribe Sophoreae (Bentham, 1862; Ducke, 1939; Rudd, 1965) because of its free keel petals and staminal filaments. Recent phylogenetic evidence, however, reveals that Sophoreae is polyphyletic (Käss & Wink, 1997; Doyle et al., 2000; Pennington et al., 2001), and that Ormosia is the sister of the Genistoid clade (Pennington et al., 2001; Wojciechowski et al., 2004; Lavin et al., 2005). Although Yakovlev (1971, 1972) segregated Ormosia in six genera, it has been accepted as a single genus (Polhill, 1981; Pennington et al., 2005), which can be diagnosed by the combination of its well formed, clearly imbricate calyx lobes; incurved style with a terminal or oblique (usually bilobed) stigma, and seed with a hard testa that is often red, black, or bicolored (Rudd, 1965; Polhill, 1981).
Ormosia had its American species revised by Rudd (1965). It is among the several papilionoid genera bearing a very conservative floral morphology (Polhill, 1981; Pennington et al., 2000), and so, presents few taxonomically useful floral characters for distinguishing between species (Rudd, 1965). As a result, Rudd (1965) based her work almost entirely on fruiting and leaf features for improving the taxonomy of Ormosia. Moreover, the use of floral characters has been neglected due to the difficulty in finding complete material among herbarium specimens.
During the course of a taxonomic study of the tribe Sophoreae in Bahia State (Cardoso et al., unpublished data), it was found that one specimen of Ormosia recently collected only in fruit presents a set of striking characters that does not match any known species of the genus. As the present taxonomic species circumscription within Ormosia is mostly based on overall fruit morphology (Rudd, 1965), the new species is herein described and illustrated based only on the fruit sample.
Ormosia timboënsis inter species sectionis Ormosiae seriei Coccinearum venis tertiaribus foliolorum tenuiter reticulatis, fructibus laevibus, seminibus bicoloribus, rubris et nigris pertinens, sed seminibus manifeste amplioribus, 18–23 × 18–19 × 12.5–13.5 mm et 9.5–11 × 2–3.9 mm (species seriei ceterae minores 6–17 × 6–17 × 5–11 mm et 1–3.5 × 1–1.5 mm) et fere omnino nigris praeterea aream circum hilum rubram (non seminibus pariter bicoloribus rubris et nigris vel in speciebus seriei ceteris seminibus rubris praeter aream cristam chalazianam secus nigram) differt.
Tree up to 20 m high, stem with bark shallowly fissured, with apex of branchlets finely fulvo-puberulent. Stipules not seen. Leaves 8–18 cm long, imparipinnate, rarely paripinnate, (2–)3–5-foliolate; pulvinus 3.5–5 × 2 mm, terete; petiole 1.8–3.5 cm long, fulvo-puberulent; rachis 1.5–4 cm long, or absent in the 2-foliolate leaves, interfoliolar segments decreasing in length distally, larger segment 1.5–3 cm long; petiolule 4–7 × 1.4–1.7 mm, terete; leaflets 5.5–11 × 2.3–4 cm, opposite, chartaceous, elliptic, base obtuse, apex acute, the upper surface glabrous or nearly so, sparsely and minutely apressed-pubescent, the lower surface finely puberulent, midvein abaxially prominent, major secondary veins in 9–11 pairs, brochidodromous, conspicuous on both surfaces, mostly 4–9 mm apart, forming angles of ca. 60° with the midvein. Flowers not seen. Fruit ca. 5.5 cm long, ca. 3.5 cm broad, ca. 2 cm thick, dehiscent, widely obovate, apex rounded, surface not rugose, glabrous at maturity, 1-seeded, the valves lignous, 2.4–3.5 mm thick. Seed 18–23 mm long, 18–19 mm broad, 12.5–13.5 mm thick, bicolored black and red, almost entirely black, red only around the hilum, discoid, slightly compressed; hilum narrowly elliptic, 9.5–11 mm long, 2–3.9 mm broad.
Etymology.—The epithet “timboënsis” is after Serra do Timbó mountain range, the type locality.
Distribution and ecology.—Ormosia timboënsis seems to be narrowly endemic to the Serra do Timbó mountain range, a remnant of Atlantic Rain Forest at municipality of Amargosa, in central Bahia State, Brazil. This new species was found as a very small population occurring in a fragment of dense humid montane forest at 750–900 m above sea level. It was collected only in fruit in January.
Conservation.—The Atlantic Rain Forest remnant in central Bahia State where O. timboënsis occurs has only recently had its flora intensively studied (Jardim et al., unpublished data). As a result, putatively new species of different families have also been collected there, such as Bertolonia (Melastomataceae, A. Amorim - CEPEC, pers. comm.), Dichorisandra (Commelinaceae, L. Aona - UNICAMP, pers. comm.), Eremocaulon (Poaceae, F. Moreira - HUEFS), and Passiflora (Passifloraceae, T. S. Nunes - HUEFS, pers. comm.). This suggests it is possible that the Atlantic Rain Forest remnants may still contribute considerably for improving even more the impressive richness and endemism observed in the Bahian Atlantic Forest (Thomas et al., 1998, 2003; Martini et al., 2007). Considering that the distribution range of O. timboënsis is so restricted and its place of occurrence is being indiscriminately exploited for gathering timber trees, we consider the species critically endangered (following the criteria B-1-a, b of IUCN 2001).
Comparison of the diagnostic morphological characters of Ormosia timboënsis with the different American sections and series of the genus according to Rudd (1965).
Lower surface of leaflets
Secondary veins of leaflets
Seed size (mm long)
Hilum (mm long)
Ormosia timboënsis (series Coccineae)
9–11 pairs, straight
dehiscent, glabrous, not septate, valves lignous, smooth
bicolored black with red patch around the hilum
All remaining species of series Coccineae
pubescent, puberulent or nearly so
9–20 pairs, straight
dehiscent, glabrous, not septate, valves lignous or coriaceous, smooth
bicolored red with black patch along the chalazal edge
pubescent to tomentose
8–18 pairs, straight
dehiscent, glabrous, not septate, valves coriaceous to sublignous, reticulate-rugose
bicolored red and black
glabrous or puberulent to sericeous
9–15 pairs, straight
indehiscent or tardily dehiscent, pubescent, not septate, valves coriaceous to sublignous, smooth
unicolored yellow to red or bicolored yellowish with red or red with black
glabrescent or pubescent to tomentose
8–20 pairs, straight
dehiscent, densely velutinous or tomentose, not septate, valves lignous, smooth
bicolored red and black or rarely unicolored red
sericeous, minutely velutinous, or tomentose
10–50 pairs, straight
dehiscent, minutely velutinous to sericeous or glabrescent, not septate, valves coriaceous, smooth
irregularly bicolored red and black or completely unicolored red to nearly all black
glabrescent to sericeous
10–16 pairs, straight
dehiscent, glabrous, septate between the seeds, valves carnose-coriaceous, smooth
unicolored dark red
pubescent or glabrous
5–12 pairs, straight
dehiscent, glabrous, not septate, valves coriaceous to lignous, smooth
5–9 pairs, arcuate
indehiscent, glabrous, not septate, valves lignous, smooth
unicolored red or reddish brown
5–9 pairs, arcuate
dehiscent, glabrous, not septate, valves coriaceous, smooth
unicolored red or black
< 3, elliptic
Within series Coccineae the most similar species to O. timboënsis is O. arborea (Vell.) Harms, which is also a large tree occurring in the Atlantic Forest of Eastern Brazil. Nevertheless, O. timboënsis is easily distinguished by leaves that are mostly 3–5-foliolate (vs. 7–11-foliolate in O. arborea) and 8–18 cm long (vs. up to 45 cm long in O. arborea), and by leaflets that are elliptic (vs. elliptic-oblong to ovate in O. arborea), in addition to the larger seed and hilum.
Although the long hilum is reported for several Asian species of Ormosia, in the neotropics this character is known only within the small section Macrocarpae (Rudd, 1965). This section includes two species bearing large seeds with a linear hilum that is 25–40 mm long. In section Macrocarpae the leaflets are glabrous on both surfaces, the secondary veins are arcuate and in 5–9 pairs, and the fruit is indehiscent with seeds that are unicolored red or reddish brown, which are all characters that distinguish this section from O. timboënsis (Table I).
Thanks are due to Dr. Luciano Paganucci de Queiroz for writing the Latin diagnosis and numerous suggestions that greatly improved the manuscript; Carla de Lima for the beautiful drawing; Márcia Neves, José Lima, Josival Souza, and Sr. Manoel for the assistance in the field work; and Centro Sapucaia and Projeto Timbó MMA/PDA for providing financial support during field work. The critical comments by Dr. Ana Maria Goulart de Azevedo Tozzi and an anonymous referee are gratefully acknowledged. This paper is part of the MSc. thesis of DBOSC prepared in the Programa de Pós-graduação em Botânica (PPGBot-UEFS) and supported by a grant from CNPq (Process 131147/2007-2).