Cassiinae pt 1 NY-Botanical_gardens_Vol. 35_1 - Copy.pdf - Antbase

1982] CASSIINAE—SENNA 173
petiole; gland ascending from slightly above first pair, slenderly lance-ellipsoid
acute or obtuse 0.5-1 mm diam, short-stipitate or sessUe, glabrous or rarely his­
pidulous, in profile (2-)2.4-3.8 mm taU; pulvinules variably swollen (l-)1.3-2.7
mm; distal pair of lfts sharply divaricate from If-stalk, very obhquely ovate-obovate
or ovate-eUiptic, broadly obtuse to broadly deltate-acute 23-60 x 12-32
mm, ±2-1.3 times as long as wide, at base cordate on proximal and rounded to
cuneate on distal side, the margin revolute, the ± excentric, almost always in­
curved midrib and 5-8(-9) pairs of camptodrome secondary veins finely promi­
nulous on upper and sharply so on lower face, the rare intercalary secondary and
tertiary venulation faint, further reticulation yet fainter or obsolete.
Peduncles with raceme-axis stiffly incurved-ascending, proximally stout but
tapering distally, mostly (1-) 1.5-5.5 cm, the racemes (2-)3-9(-12)-fld, when
young or when few-fld subumbellate; bracts ovate or lanceolate acute or acuminulate
1.5-3.5(-4) X 1-2.4 mm, at base not or only narrowly embracing base of
pedicel, deciduous before or very soon after anthesis; pedicels (9-)12-20(-24)
mm, early thickened except at very base; buds subglobose, subappressed-pUo­
sulous, rarely glabrescent; sepals yellowish or sometimes red-hneolate, the inner
subpetaloid, strongly graduated, the smallest outermost Vi-% the largest inner­
most, all ovate-, obovate-orbicular or broadly oblong-obovate very obtuse, faintly
veined, the longest 8.5-11.5 mm; petals yellow or orange-yellow, puberulent dorsally,
3 adaxial broadly obovate- or flabellate-cuneate up to 13-18(-21) mm, the
2 abaxial longer and narrower, up to (15-) 17-29 mm, one of them obhque and
incurved around 2 longer stamens; filaments glabrous, those of 4 median stamens
1.5-2.6 mm, those of 3 abaxial ones 2.2-5 mm; anthers glabrous or exceptionally
very sparsely puberulent, those of median stamens 4.5-6 mm, with introrsely
2-porose beak 0.2-0.4 mm, those of abaxial ones no longer and usually a trifle
smaller, 3.5-5 mm with porrect 2-porose beak 0.5-0.9 mm; ovary densely yellowish-pUosulous;
style glabrescent 2-2.7(-3) mm, at apex gently incurved and
0.35-0.6 mm diam, the stigmatic orifice 0.2-0.3 mm diam; ovules 76-108.
Pod stiffly spreading-ascending, stoutly short-stipitate, the stipe 3.5-7 mm, the
narrowly cyhndroid body 4-9.5 x 0.7-0.95 cm, abruptly contracted at each end,
usually a little decurved, the valves becoming papery blackish lustrous, thinly
pilosulous, apparently indehiscent, the seeds released only by rotting ofthe fruit;
seeds biseriate, turned broadside to the septa, embedded in fetid pulp (black when
dry), compressed-obovoid 4.1^.6 mm, the testa briUiantly glossy-castaneous, a
faintly differentiated areole ±3.5-3.8 x 2.3-2.7 mm on each face equally glossy
or slightly roughened.—CoUections: 72.
Open forest, riverine forest and thickets of sand-savanna, both on varzea and
terra firme, becoming locally abundant in capoeira and along highways, mostly,
perhaps always, below 300 m, common on the coastal plain and interior lowlands
of Guyana (Courantyne vaUey), French Guiana, Surinam, and n.-e. BrazU (Ama­
pa, Para and Maranhao), ascending the Amazon and Rio Branco w., in e. Ama­
zonas and Terr, do Roraima, to ±6rW, and s. on Rio Araguaia into extreme
n.-w. Mato Grosso.—Fl. (VI-)VII-XII(-III).
In its area of dispersal S. chrysocarpa is readUy recognized by a combination
of relatively small leaflets, a soUtary petiolar gland, a narrow thyrsiform panicle
of subumbellate racemes, and short indehiscent pulpy pods spreading-ascending
on stiffened pedicels. It is closely related to the somewhat smaller-flowered,
almost isandrous S. insularis endemic to Cuba and to 5. rizzinii, which replaces
it in Brazil east- and southward from Ceara; when better known these three may
well emerge as no more than geographic expressions of one polymorphic species.