Dinizia excelsa Ducke

Lewis GP et al. 2017. The majestic canopy-emergent genus Dinizia (Leguminosae: Caesalpinioideae), including a new species endemic to the Brazilian state of Espírito Santo. Kew Bulletin 72:48. DOI 10.1007/S12225-017-9720-7

Type

Type: Brazil, Obidos, Serra do Curumu, 4 Jan. 1914, Ducke s.n. (lectotype MG 15304!, designated here), remaining syntypes: Ducke s.n. (MG nos. 15774, 15826, 15989, 16177, 17073).

Morphology General Habit

A canopy emergent tree, (15-)30- 60 m+, unarmed, trunk cylindrical, bole of larger specimens 15 - 22.5 m, up to 3 m in diam at soil level, DBH (23 -)80cm- 2 m, moderately to strongly buttressed, the buttresses to 4 - 5 m tall (and these “continue off into the forest as raised, laterally compressed roots up to 80 cm high”, Zarucchietal. 2936), crown spreading; bark smooth, white, breaking off in woody plates to reveal a light red-brown or brick-red under bark; heartwood brown to red, without streaks

Morphology Leaves Stipules

Stipules subulate, 3 – 6 mm long, caducous

Morphology Leaves

Leaves bipinnate, eglandular, the petiole terete, 2- 7.5 cm long, the rachis(4-)6- 28 cm long, caniculate, puberulent; pinnae in 3 - 6 subopposite to strongly alternate pairs, or odd- pinnate with one extra pinna on one side (i.e. total pinnae per leaf 7 to 11 (- 13)),the pinnae 6.5- 12.5 cm long, the rachis caniculate with raised ridges along each side of the channel, puberulent to pubescent; leaflets alternate, in 7 - 14 pairs per pinna, subsessile, oblong, subelliptic, to trapeziform, 12 - 25x5- 11 mm, leaflet apex retuse to rounded, base truncate, inequilateral about the midvein, the lamina much broader on the distal side of the midvein base, the midvein otherwise subcentral to diagonal, secondary venation brochidodromous, but hardly visible, lamina discolorous, the upper surface darker, glabrous (except for a few hairs on the slightly immersed midvein) and nitid, the lower surface sparsely puberulent to glabrescent, including on the prominent midvein, the margins revolute, the pulvinule fleshy, cone-shaped, puberulent

Morphology Reproductive morphology Inflorescences

Inflorescence a multi-branched, terminal com­pound raceme, its rachis puberulent; individual racemes over 150-flowered, the peduncle 3 - 15 (- 20) mm long, the rachis (8-) 12.5 – 16 cm long, the raceme 1 - 1.5 (-2) cm wide in open flower; flowers mostly functionally male (the gynoecium supressed or lacking), fewer flowers in each individual raceme hermaphrodite, all flowers 4 - 5 mm long (from base of pedicel to apex of petals), whitish green to greenish yellow, fragrant, short-pedicel­late, the pedicel 0.5 - 1 mm, a persistent to caducous, lanceolate, pubescent, 0.5 mm bract at the base of each flower pedicel, bracteoles lacking, buds globose, the petals exposed early in development; the pedicel, hypanthium, calyx tube and its 5 equal, short, broadly triangular lobes all puberulent with white hairs, the lobe margins ciliate, the hypanthium and calyx tube together 1 - 1.25 mm long; petals 5, free, imbricate, obovate to elliptic, lacking a distinct claw, slightly hooded to dorsally concave, 3 - 4 x 2 - 2.25 mm, sparsely hairy along a central vertical line on the dorsal surface, glabrescent, the margin sparsely to moderately ciliate

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 10, white, 3x petal length, the filaments 10 - 12 mm long, very shortly fused at their bases and attached as a ring to the rim of the hypanthium, anthers uniform, dorsifixed, 0.6 - 0.7 mm, anther glands lacking, staminodes lacking

Morphology Reproductive morphology Flowers Gynoecium

Gynoecium red, glabrous, the base short-stipitate, style terminating in a slightly flared (funnel-shaped) hollow stigma

Morphology Reproductive morphology Fruits

Fruit wine-red coloured when fresh (Simon et al. 1452), laterally compressed, coriaceous, glabrous, indehiscent, 20.5 -35 (including a 1.5 - 2 cm stipe) x 4.5 - 8.5 cm, the sutures longitudinally wrinkled and appearing almost winged, the upper “wing” ± 1 cm wide, 7 - 12-seeded

Morphology Reproductive morphology Seeds

Seeds oblong to elliptic, sometimes slightly narrower in the middle, (10 -)14 - 15 x 6 - 7 mm, laterally compressed, black, hard (the texture of a pebble), the surfaces with a network of minute fracture lines, pleurogram absent, the apex narrowing to a terminal funicle attachment, < 1 mm

Morphology Reproductive morphology Flowers Pollen

Pollen in acalymmate tetrahedral tetrads with the individual grains 3- colporate, and ornamentation gemmate in the polar areas and clavate in mesocolpial areas

Morphology Roots

Root nodules lacking.

Distribution

Guyana, Suriname and Amazonian Brazil (in the northern and central-western states of Amapa, Amazonas, Mato Grosso, Para, Rondonia, Roraima and Tocantins). Also recorded from the state of Acre by Lorenzi (1992).

Ecology

The species clearly prefers non-flooded environments and is recorded from non-inundated moist forest, non-flooded upland mixed forest, “floresta ombrofila mista”, tropical forest on terra firme, tropical upland evergreen forest and tropical dry forest, at elevations from 50 - 490 m.

Conservation

Dinizia excelsa is geographically widely dispersed in seven Brazilian states, Guyana and Suriname and has a tendency to be gregarious ( Forest Dept. of British Guiana field no. D128, record no. 2119; and da Silva et al.1977). The estimated extent of occurrence (EOO) exceeds the thresholds for a threatened category according to IUCN criteria version 3.1 (IUCN2012) and it is suspected that the area of occupancy (AOO) also exceeds these thresholds. It is therefore assessed as being of Least Concern, although it is not known how frequently encountered the tree is today across its distribution range, and it is evident from the literature that its wood has been widely used (see under notes). The species is not protected under CITES regulations.

Phenology

Collected in flower in Brazil from April to August, and in fruit throughout the year (no fruiting collections seen from February or March); in Brazil the main flowering period in most states is July and August; collected in flower in Guyana in August and September and in fruit in May and July, and in Suriname a single fruiting specimen (in K) was collected in February.

Vernacular

“Angelim”, “angelim pedra”, “angelim vermelho”, “parica” (Brazil); “Awaraime” (Trio, Suriname); “parakwa” (Wapisiana, Guyana). Lorenzi (1992: 176) also includes the popular names: “angelim falso”, “faveira”, “faveira-dura”, faveira-ferro” and “faveiro-do-grande”.

Note

The species is notable for the hardness of its wood and its bark breaking off in woody plates which accumulate in piles at the base of the tree. Usually the most terminal raceme in the compound inflorescence flowers first, then the basal racemes open, followed by those above; the flowers in each raceme open somewhat irregularly, but generally from the base to the apex of the raceme; freshly opened flowers are strongly fragrant( Nee &Dick46239). Dinizia excelsa is reported to be pollinated by bees (Ribeiro et al. 1999). The wood is very resistant and difficult to work, but has been widely used for railway sleepers, in civil and naval construction, cabinetwork and joinery (da Silva et al. 1977), and for battens, props, beams, girders, posts, stakes, door and window frames, floor boards, carts, wagons and bridges (Lorenzi 1992). The wood density of D. excelsa is recorded as between 0.83 - 0.91 g/cm3 by Fearnside (1997) and as 0.9 - 1.2 g/cm3 by Richter & Dallwitz (online version 2009), who also describe the wood odour as distinct, very unpleasant and persistent. In the protologue of Dinizia excelsa, Ducke (1922) cited six specimens that he had collected in Para between 1914 and 1918 (MG herbarium numbers: 15304, 15774, 15826, 15989, 16177 and 17073) without choosing a holotype. The six collections should thus be considered as syntypes; all are still housed in the Museu Goeldi (MG) herbarium, with some duplicated in the herbarium of the Rio de Janeiro Botanic Gardens (RB). A number of the specimens in MG carry original field labels in Ducke's handwriting, but no one specimen bears both flower and fruit material. The specimen in the best condition, which fits the description of foliage and fruits presented in the original description, and which includes an original label in Ducke's hand, is MG15304 from the Serra do Curumu collected on the 4th of January 1914. This specimen is thus designated as the lectotype of D.excelsa. The other specimens cited in the species’ protologue become remaining syntypes.