Ormosia altimontana Meireles & H.C. Lima, 2013

Meireles, Jose Eduardo & Lima, Haroldo Cavalcante De, 2013, A new species of Ormosia (Leguminosae, Papilionoideae, Sophoreae) from the Brazilian Atlantic Rain Forest, Phytotaxa 143 (1), pp. 54-60 : 55-58

Ormosia altimontana Meireles & H.C. Lima , sp. nov. ( Figures 1 and 2 )

Ormosia altimontana differs from O. friburgensis and O. ruddiana by a combination of fewer leaflets (5–7 versus 9–13), with longer pulvinules (4 –10 mm versus 1–4 mm), a densely tomentose golden to fulvous abaxial surface, and prominent secondary veins, and slightly longer flowers (11–12 mm long versus 8–10 in O friburgensis , flower length unknown in O ruddiana ).

Type:— BRAZIL. Rio de Janeiro: Nova Friburgo, Reserva Ecológica de Macaé de Cima , Rio das Flores, Trilha para o Pirineus , 13 December 1997 (fl), H.C. de Lima et al. 5515 (holotype RB!, isotypes NY!, K!, SPF!)

Trees to 20 m high; young branches, stipules, leaves, inflorescences and fruits densely to sparsely tomentose with golden to fulvous hairs; stipules triangular, 10–12 × 8–10 mm, tomentose, early caducous. Leaves alternate, imparipinate, petiole (1.5–) 2.5–3.5 (–5) cm long, rachis (2.8–) 4.5–6.5 (–9) cm long; leaflets 5–7, opposite, the pulvinule wrinkled, (4–)5–7(–10) mm long, the blade elliptic to oblong, rarely ovate, coriaceous, 4–10 × 1.5–4 cm, basally attenuate to obtuse, apically acute, rarely obtuse, the margins revolute, the adaxial surface glabrous, the abaxial surface tomentose with golden to fulvous hairs, the secondary veins prominent abaxially, 9 to 14 pairs, essentially straight and parallel, diverging from midrib by 45º to 60º angles. Inflorescences paniculate, terminal, densely to sparsely tomentose; bracts lanceolate, 3.5–4 × 1 mm. Flowers papilionoid, 11–12 mm long; pedicel 1 mm long, bracteoles 2, lanceolate, 2.5 × 0.5 mm, attached to the base of calyx; calyx campanulate, 8 mm long, the base gibbous, the tube 5 mm long, the teeth triangular, 3 × 2,5– 3 mm, the apex acute; corolla violet, the standard orbicular with the blade 9 × 9 mm and the claw 3 mm long, the wings oblong with the blade 8 × 2.5–3 mm and the claw 2 mm long, the keel petals free, obovate in outline, with the blade 7–7.5 × 3–3.5 mm and the claw 2.5 mm long. Stamens 10, filaments free, alternating long and short, varying from 4 – 7 mm long; anthers slightly dimorphic, ca. 0.5 mm long on the long stamens and ca. 0.3 mm on the short ones. Gynoecium 8.5 mm long; stipe 0.5 mm; ovary 4.5 mm long, tomentose; style 3.5 mm long, curved; stigma entire, papillate. Fruits indehiscent, 3–4.5 × 2– 2–7 cm, woody, the seed chamber inflated; young fruit wrinkled, densely tomentose with golden to fulvous hairs; mature fruits sparsely tomentose to glabrous, brown. Seeds 1 (–2) per fruit, essentially globose to slightly elliptic, rarely dorsoventrally compressed, 1.2–1.6 x 1.4–2.2 x 1.4–1.8 cm, testa deep red, orange/yellow surrounding the hilum; hilum elliptic to oblong, 4–6 × 2 mm.

Additional specimens: — BRAZIL. Rio de Janeiro: Mun. Nova Friburgo, Reserva Ecológica de Macaé de Cima, trilha para pedra da Bicuda, 22ºS, 43º03’W, 17 August 1990 (fr), M.P.M. de Lima et al. 201 (RB! K! SP!); Sitio Bakus, elevacão na frente da casa, 22º22’30.2’’S, 42º29’44.8’’W, 1450 m elev., 26 January 2006 (fr), H.C. de Lima et al. 6417 (RB!, UEC, K, MBM, NY); Sitio Bakus, Mata de encosta no topo do morro, 16 January 2008 (immat fl), H.C. de Lima et al. 6844 (RB!); Sitio Bakus, CTI, Mata de encosta no topo do morro, 17 January 2008 (immat fl), H.C. de Lima et al. 6852 (RB!); Sitio Sophronithes. Trilha por trás da casa, beirando o Rio das Flores, 16 February 2008 (immat fr), J.E.Meireles et al. 575 (RB!); Picada da Pedra Branca , 28 December 1989 (fr), M. Nadruz 547 (RB!) .

Distribution and phenology:— Ormosia altimontana is known only from the municipality of Nova Friburgo, occurring at elevations above 1000 m in the upland Atlantic forest. Ormosia altimontana was collected with flowers in December and February, and with fruits from the end of February to December.

Discussion:— According to Rudd (1965) in her infrageneric classification for the American species of Ormosia , O. altimontana should be assigned to section Ormosia , series Excelsae Rudd (1965:309) due to the secondary veins of the leaflets being essentially straight and parallel and the pods indehiscent.

The new species is morphologically related to O. friburgensis Taub. ex Harms (1924: 290) and to O. ruddiana Yakovlev (1970: 129) . All three species have large, globose, deep red to orange colored seeds. However, O. friburgensis and O. ruddiana have more numerous [(7–) 9–13 versus 5–7], thinner leaflets with less conspicuous secondary veins, a glabrate (versus tomentose) abaxial surface, and shorter pulvinules [(1–)2–3(–4) mm long]. The flowers of O. ruddiana are unknown, but the flowers of O. friburgensis tend to be shorter than those of O. altimontana [8–10(–11) mm versus 11–12 mm].

The results of the Principal Component Analysis of morphometric measurements of vegetative traits for the three closely related species is presented in Figure 3 . The ordination shows that O. altimontana specimens form a distinct cluster that is clearly separate from another cluster containing specimens of O. friburgensis and O. ruddiana . That separation occurs mainly along Component 1 (x axis on figure 3), which seems to be mostly associated with the traits: hair density (‘HairDensity’), secondary vein number (‘SecondVein_N’), pulvinule length (‘Pulvinule’), and leaflet number (‘Lflt_N’). On the other hand, traits related to leaflet dimension (‘Lflt_W’ and ‘Lflt_L’) and rachis length (‘Rachis’) were mostly associated with intra specific variation. The distinction between specimens of O. friburgensis and O. ruddiana is less clear, but revisiting the delimitation of these two species is beyond the scope of this study.

In spite of growing in the same geographic region, O. altimontana does not co-occur with O. friburgensis . The new species is only found in elevations above 1000 m whereas O. friburgensis grows at lower altitudes. Extensive fieldwork has been conducted in the Macaé de Cima region and these two species were never found together. More importantly, no specimen with intermediate morphology between the O. friburgensis and O. altimontana was ever found.

Thus, we conclude that morphological and ecological differentiation between O. altimontana and O.ruddiana and O.friburgensis are sufficient to support the recognition of O.altimontana as a new and distinct species.

Figures

FIGURE 1. Ormosia altimontana A. fruiting branch. B. abaxial leaflet surface, showing the tomentose indument. C. seeds in hilar and lateral view. D. flower. E. standard petal. F. wing petal. G. keel petal. H. anthers, slightly dimorphic. I. dimorphic stamens. J. gynoecium. K. stigma. Branch and fruits (A–C) after M.P.M. de Lima 201. Flower (D–L) after H.C. de Lima 5515.

FIGURE 2. Ormosia altimontana A. Leaflets showing golden indument on the abaxial surface. B. Globose, red to orange seeds.

FIGURE 3. Principal Component Analysis of vegetative traits in O. altimontana, O friburgensis and O. ruddiana (See Appendix 1).