Subfamily: Faboideae.
Phylogenetic Number: 3.1.08.
Tribe: Swartzieae.
Group: Lecointea.
Species Studied - Species in Genus: 2 studied; 4 in genus.
Fruit: A legume; unilocular; 2.4–3.7 cm long; 1.5–4 cm wide; 1–4 cm thick; length less than twice as long as width; with deciduous androecial sheath; with deciduous corolla; with deciduous calyx; without orifice formed by curving of fruit or fruit segments; straight; not plicate; not twisted; symmetrical; circular, or elliptic (oblong), or oblong; not inflated; compressed, or terete; without beak, or with beak; straight; with solid beak the same color and texture as fruit; rounded at apex; aligned with longitudinal axis of fruit; short tapered at base, or rounded at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; fleshy (when fresh), or leathery (upon drying); seed chambers externally invisible; margin not constricted; margin without sulcus; margin plain; wing(s) absent; substipitate; indehiscent. Replum invisible. Epicarp dull; monochrome; green (when young), or brown (purplish); with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features; not veined; not tuberculate; wrinkled; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thick; surface not veined; 1-layered; without balsamic vesicles; without fibers; without reniform canals; solid; coriaceous. Endocarp present; visible; glossy; opaque; monochrome; reddish brown; spongy; without adhering pieces of testa; subseptate; with septa thicker than paper, firm; coriaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) (1–)2; length parallel with fruit length, or transverse to fruit length; touching, or neither overlapping nor touching; in 1 series. Funiculus 2 mm long; of 1 length only; thick; straight. Aril absent.
Seed: 8–30 mm long; 4–15 mm wide; 3.5–8 mm thick; overgrown, 1 seed filling entire fruit cavity; angular, or not angular; asymmetrical; circular, or D-shaped, or elliptic, or oblong, or ovate, or reniform (rarely); compressed; with surface smooth; without visible radicle and cotyledon lobes; without hilar sinus; without umbo on seed faces; without medial ridge on each face. Cuticle not exfoliating; not inflated; not wrinkled. Testa present; without pieces of adhering epicarp; not adhering to endocarp; free from endocarp; dull, or glossy (because of exudates from endocarp); not modified by a bloom; colored; monochrome; reddish brown; glabrous; not smooth; with elevated features; veined (oblique and parallel), or shagreen; coriaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible; without faboid split; larger than punctiform; 0.3–20 mm long; with angular outline; irregular; subapical to radicle tip; flush; not within corona, halo, or rim. Lens not discernible. Endosperm absent. Cotyledons without lobes; with the interface division terminating at base of radicle. Embryonic axis without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon.
Yakovlev (1976) revised the genus, and transferred the Central American Zollernia tango P.C. Standley into Lecointea. Barneby (1989a) reviewed the South American species of the genus. He synonymized Beliceodendron C.L. Lundell, of which B. tango (P.C. Standley) C.L. Lundell is the type species, with Lecointea, and proposed that L. tango may be synonymous with L. amazonica. The cotyledonary and embryonic structures of L. amazonica (Cid & Ramos 2941 (BARC)) and L. tango (Gentle 7043 (BARC)) are very different from each other and from the remainder of the Faboideae. In L. amazonica, the embryo is in the center of the cotyledons with a small cavity at its radicular end (Figs. E, F). One cotyledon is much smaller than the other one, and the larger cotyledon completely surrounds the smaller one. In L. tango, the cotyledons are apparently fused along their entire margins approximately 1/4 of their width, and tightly appressed at their centers, but not fused (Fig. G). On the funicular side of the fused cotyledons, there is a small discoid structure, approximately 2 mm in diameter and 0.6 mm in thickness, within which the embryo is located (Figs. G, H). On the inner side of the discoid structure, there is a small cavity into which the rudimentary plumule projects. Harendeen (1994) proposed that Lecointea belongs to a clade also including Holocalyx (3.1.12), Harleyodendron (1.09), Exostyles (1.10), and Zollernia (1.11) and that Lecointea is most closely related to Holocalyx. The seeds of Holocalyx are anomalous in Sophoreae (2) with their fused cotyledons and rudimentary embryo. The reduced embryo of L. amazonica and the fused cotyledons of L. tango are somewhat similar to those of Lecointea, and therefore support Herendeen's hypothesis.
Tribe Swartzieae
Swartzieae has been assigned to Caesalpinioideae (Cowan, 1968), Swartzioideae (de Candolle, 1825a, 1825b; Corner, 1976), and Faboideae (Bentham, 1865, Hutchinson, 1964, Cowan, 1981). In 1968, Cowan (1968) was unable "finally to resolve the sub-familial relationship of Swartzia," but in 1981, he (Cowan 1981) placed it in the Faboideae and stated, "... features appear to support the arrangement adopted here (Cowan 1981) with the Swartzieae representing a relatively less-advanced position in the Papilionoideae (Faboideae). This conclusion is now supported by wood anatomy ..., by nodulation proclivity ..., and by chemistry ...; chromosome numbers of n=8, 10 or 14 ..., as well as pollen morphology ..., do not negate this conclusion." In the most recent assessment of the Fabaceae, Polhill (1994a, 1994b) maintained Swartzieae as a basal tribe of Faboideae, "transitional to the Caesalpinioideae." He transferred four genera from Sophoreae (2) into the Swartzieae, Amburana (3.1.15), Ateleia (3.1.13), Cyathostegia (3.1.14), and Holocalyx (3.1.12), and arranged the genera in four groups corresponding to clades in Herendeen's (1994) cladistic analysis. Herendeen carried out cladistic analyses using morphological characters of all Swartzieae genera, 19 genera of Sophoreae, and three Caesalpinioideae genera. He concluded that Swartzieae is polyphyletic and that it should be disbanded and its genera transferred to Sophoreae. Preliminary rbcL data (Doyle et al. 1997) supported his conclusions. Ireland et al. (2000) also carried out molecular phylogenetic studies. They also concluded that Swartizeae is polyphyletic, and suggested that possibly tribe Swartzieae could be maintained with Swartzia (3.1.01), Bobgunnia (3.1.01A), Bocoa (3.1.02), Ateleia (3.1.13), Cyathostegia (3.1.14) and the current remaining Swartzieae genera transferred to other tribes. Our seed data neither support nor refute the overall outlines of Herendeen's cladograms; they are discussed below for a few genera. Ferguson and Skvarla (1991) reported on the pollen morphology of Aldina and Swartzia (1.01), and the nine other genera of Swartzieae are covered in Ferguson and Skvarla (1988). Their data are summarized in a computer-generated key in Vezey et al. (1991). The pollen data for the tribe should be compared with our seed-fruit morphological data.
Authors: J.H. Kirkbride, Jr., C.R. Gunn, A.L. Weitzman, M.J. Dallwitz, K.R. Thiele
Content last updated April 2003
Released April 2024 on idtools.org
