Abarema alexandri (Urb.) Barneby & J.W.Grimes
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Authors
Rupert C. Barneby
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Authority
Barneby, Rupert C. & Grimes, James W. 1996. Silk tree, guanacaste, monkey's earring: a generic system for the synandrous Mimosaceae of the Americas. Part I. Abarema, Albizia, and allies. Mem. New York Bot. Gard. 74: 1-292.
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Family
Mimosaceae
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Scientific Name
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Type
"Habitat in Jamaica: Alexander [Prior]." - Holotypus, presumably †B; neotypus (dated 1850, fl.), Prior s.n., GOET!; isotypi, K!, NY!
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Description
Species Description - Trees attaining 12 m, either macro- or microphyllidious, the young branchlets, lf-axes and inflorescence at first villosulous with brown-gold spreading hairs ±0.1-0.25 mm but early glabrescent or finally glabrate, only the axillary buds of mature stems tomentulose, the thin-textured, delicately venulose lfts bicolored, bright green above, paler duller beneath, the loose spiciform racemes of small greenish- yellowish fls arising singly or 2-3 together from the axil of coeval lvs, the fruits long persistent, immersed in foliage. Stipules 0. Lf-formula (i—)ii—vii/4—15; lf- stks (2—)3—15 cm, the petiole 1.3-4.5 cm, the longer interpinnal segments 1.2-3 cm; nectary immediately below insertion of first pinna-pair sessile, shallow-cupular or almost plane, in vertical view round or broadly elliptic 0.8-1.7 mm diam, similar but smaller ones at some further nodes of lf-rachis and at all or most nodes of pinna-rachises; pinnae accrescent distally but the penultimate pair often longest, the rachis of these 5-12 cm, the longer interfoliolar segments 6-25 mm; lft-pulvinules in dorsal view 0.3-1.6 x 0.5-0.9 mm; lfts decrescent proximally but otherwise, except for proportionately narrower furthest pair (no further described), subequiform and all obtusely rhombic or rhombic-elliptic around a diagonal midrib, at base inequilaterally broad-cuneate (or postically rounded), obtuse muticous at apex, those at and beyond midrachis 11-60 x 6-41 mm, 1.5-2.4 times as long as wide; the midrib straight or slightly arched forward, the secondary veins ascending at ±45° to anastomosis well within the plane margin, these and random tertiary veinlets subequally prominulous on both faces of blade. Peduncles 3.5-8 cm; raceme-axis 2.5-8 cm, the fls horizontal or a little declined; bracts very quickly deciduous (none seen); pedicels of proximal fls 0.5-4 mm, those of distal fls progressively shorter, the furthest fls sessile or almost so; fls seemingly homomorphic, no dimorphic terminal one seen; perianth 5-merous, thinly puberulent externally or glabrate; calyx campanulate 2.2-3.8 x 1.3-2.5 mm, the ovate teeth (often unequal) to 0.5-0.9 mm; corolla narrowly trumpet-shaped 5.5-7.5 mm, the ovate lobes (1-) 1.7-3 x 0.8-1.6 mm; androecium 32-40-merous, the longest filaments 11-14.5 mm, the stemonozone 1.5-2.3 mm, the tube 3.5-5 mm; ovary glabrous, truncate at apex; style a little exserted, the stigma poriform or a trifle dilated, 0.1-0.2 mm diam. Pods 1 -4 per spike, in profile undulately broad-linear recurved through 3/4 to 1½ circle, 7-10.5 x 1-1.3 cm, contracted at base into a very short stipe or cuneate neck, minutely apiculate, the valves at first dark green and venulose, when ripe gray-tan and roughened, framed by thickened sutures shallowly impressed between seeds, low-convex over each of 6—10(—11) seeds, within tan between seeds but lustrous-castaneous in the seed-cavities, the interseminal constrictions 11-16 mm apart; dehiscence elastic, the valves coiling and the seeds dangling; funicles ribbonlike, coiled distally; seeds plumply obovoid, a trifle compressed, in broad view 5.5-7.5 x 4.3-6 mm, when fresh slate-blue or particolored blue and whitish, the more or less translucent testa 0.3-0.6 mm (restored by soaking) thick, in older seeds lustrous cream-colored proximally, brown or brown and indigo in a transverse band around the distal hemisphere outside the finely engraved, continuous pleurogram, this 3.3-3.8 x 2-3 mm; embryo aniline-blue.
Distribution and Ecology - In woods or thickets on limestone substrates, 350— 830 m, endemic to Jamaica, where represented by two, apparently partly sympatric varieties.
Local Names and Uses - Tamarind shadbark. [Jamaica]
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Discussion
The openly racemose units of inflorescence of A. alexandri, which are found in no other West Indian abarema, are technically indistinguishable from those of the Cordilleran species A. callejasii, A. lehmanii, A. killipii, and A. racemiflora. However, the cladogram (Fig. 4B) supports Britton & Rose in suggesting that this species is more closely related to Caribbean species of Abarema.
The foliage of A. alexandri is suprisingly variable. We maintain here two of the three infraspecific taxa traditionally based on leaf-formula.
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Common Names
Tamarind shadbark.
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Distribution
Jamaica South America|