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Araceae
Dieffenbachia aurantiaca Engl.
SUMMARY
Stout herb, 0.7-2.3 m tall; sap fetid and caustic; stems erect at apical part, to 2 m long, the older portion reclining and up to 2 m long; internodes 2.0-4(6) cm long, 5-7(10) cm diam., dark green to pale green, semiglossy to glossy, streaked with paler green; petioles 13-33(48) cm long (averaging 24 cm long), C-shaped at base in cross sectione moderately spongy, medium green, semiglossy adaxially, matte and acutely l-ribbed abaxially, the surface finely dark striate, sometimes variegated with paler green markings, sheathing 1/3 to nearly throughout (35%- 97% their length and averaging 77Wo); sheath 6.5- 25.5(38) cm long (averaging 17.7 cm), medium green, finely dark green striate, sometimes variegated with paler green markings, adaxially acute margins sometimes much paler, with margins in- curled but usually not overlapping, the apex free-ending and obliquely rounded to rounded-auriculate distally; unsheathed portion 0.5-2 cm long, angular to ± triangular in cross section, flat to bloadly sulcate adaxially (sometimes with a medial keel), adaxial margins thin and revolute, acutely keeled abaxially, abaxial margins thickly winged, sometimes with a medial keel, thin, revolute, some- times medially keeled at malgins; blades oblong- elliptic to ovate-elliptic, slightly inequilateral, one side 1-1.5 cm wider than the other side, usually subcoriaceous, acuminate to abruptly acuminate at apex, slightly inequilateral and obtuse to rounded or subcordate (rarely attenuate on one side) at base, (26)31-57 x 11-27 cm (averaging 39 x 19 cm), 1.7-2.6 times longer than wide (averaging 2 times), ranging from about as long as petioles to 2.8 times longer than petioles (averaging 1.7 times longer); margins weakly undulate; upper surface dark green, concolorous or sometimes variegated, drying dark olive-green to medium gray-green, weakly glossy to semiglossy; lower surface moderately paler, matte to weakly glossy, drying pale yellowish green; midrib flat to broadly concave above (broadly sulcate near base), 5-20 mm diam., sometimes whitish, faintly stliate above, bluntly acute to V- shaped (a continuation of the triangular petiole) be- low, drying brown below, faintly striate; primary lateral veins (8)12 to 14 per side, departing midrib at a steep angle, spreading at a 50°-70° angle, gradually spreading in a broad curve, slightly to moderately paler than surface in the proximal one-half weakly raised to convex in valleys, flat and darker than surface toward margins, drying mostly paler, sometimes darker than surface above, weakly con- vex and slightly paler than surface below, drying yellowish and paler than surface or brownish and darker than surface below; interprimary veins present or absent, usually with 1 between each pair of primary lateral veins in the lower 1/3 of the blade; minor veins darker than surface, visible but moderately obscure below. INFLORESCENCES to 3 per axil; peduncle (7)10-18 cm long, acutely angular on one side, drying striate, 3-6 mm diam.; spathe 17-25(38) cm long, 2-3.5 cm wide, flattening to 5.7-8 cm wide on tube, 2.5-6.'S cm wide at constriction, 3-4.3 cm longer than the spadix, gradually long-tappered toward apex from the middle, uniformly light green to medium green throughout; weakly glossy outside, glossy inside; spathe blade 2.5-7 c m wide when flattened; spadix 16-20(33) cm long; free portion to 15.5cm long; pistillate portion 6.5-8.5(15.5) cm long. 1.5-2 cm diam. Throughout (mostly drying 6-9 mm diam.); fertile staminate portion 7-12.5 cm long, white, tapered toward apex and weakly tapered slightly toward base; intermediate sterile segment 1.5-4 cm long, with a few scattered staminodia in upper half; pistils 51 to 72, irregularly scattered, with 3 to 4(6 to 7) across the width of the spadix, seperated from one another by ½ to 4.0 times their width, depresses-globose, to 2 mm long, 1.2-1.6(2.8) mm diam., pale green; stigmas cushion-shaped, to 2 mm high, 2.5-3 mm wide, white; stamindoia 3 to 5 per pistil, 1.5-2(3.8) mm long, free or briefly united at base, held well above the stigmas sometimes united for much of their length; synandria 1-2(3.4) mm diam., margins irregularly angled with rounded, linear to 3-sided slit medially at apex. INFRUCTESCENCE 19-24 cm long; spathe orange outside; spadix 8-15 cm long; berries red-orange, B & K yellow-red 6/2.5 to B & K yellow-red 7/5 to red B & K red 6/10 (Berlin & Kay, 1969), subglobose, ovoid to ellipsoid, 7-10 mm long.