Key D (a)
Leaves simple, cordate or subcordate at base, with posterior lobes, epunctate below.
1a. Plants scandent and twining or at least with lone slender stems with elongate Plants scandent and twining or at least with long slender stems with elongate internodes, held erect usually by rooting onto or being supported by trees; blades mostly less than 27 cm long. If not
2a. Leaves bullate; peduncle nearly non-existent, obscured by the base of spathe, rarely to 5 cm... A. clidemioides Standl.
2b. Leaves not bullate (except A. davidsoniae}; peduncles conspicuous.
3a. Stems mostly more than 2 cm diam.; blades 16-48 cm long, 11-44 cm wide....A. subsignatum Schott
3b. Stems mostly less than 1 cm diam.; Blades mostly less than 27 cm, long, 16 cm wide.
4a. Stems 2-4 mm diam., usually several meters long, twining, flexible; internodes with many short roots; sea level to 1,700 m.
5a. Leaves usually palminerved, lanceolate, cordate at base and broadest below the middle of the blade; spadix usually with a conspicuous stipe 1-2 cm long; Mexico to northern Guatemala, 1,000-1,700 m......... A. flexile ssp. muelleri (Macbr.) Croat & Baker
5b. Leaves palminerved, elliptic to narrowly elliptic, narrowly subcordate at base, broadest at or near the middle of the blade; spadix sessile or with the stipe to 2 mm long; Mexico to Panama, sea level 10 1,000 m. .... A. flexile Schott ssp. flexile
4b. Stems usually 5-10 mm diam., Usually 1 m or less long, usually stiffly erect, usually supported by a tree, not twining, the internodes lacking roots; roots long, few, restricted to the nodes; usually 1,200-2,300 m.
6a. Leaf blades all cordate or, rarely, subcordate........ A. davidsoniae Standl.
6b. Leaf blades subcordate intermixed with blades that are rounded or truncate, rarely cordate.... A. microspadix Schott
1b. Plants not scandent; internodes short.
- 7a. Species of Costa Rica and Panama, often extending into South America, sometimes into Nicaragua (A. ravenii as far north as Honduras). IF not
- 8a. Geniculum situated at least 10 cm below the base of the blade; blades subcordate; terrestrial....................... A. oerstedianum Schott
8b. Geniculum immediately subtending the leaf blade.
9a. Spadix more or less clavate, broader in circumference at apex than at base; spathe ovate-elliptic with a long-cuspidate apex, long-decurrent at base; blades drying dark brown or gray-brown; middle elevations, Cordillera de Talamanca. .................. A. clavatum Croat & Baker
9b. Spadix cylindroid or tapering from base to apex, never clavate; spathe mostly oblong, lanceolate, or ovate.
10a. Spathe purple to dark maroon or mottled green and purple throughout (excluded are species with spathe predominantly green with purple tinged margins and/or veins). If not
11a. Spathe twisted and contorted; peduncle short (less than 20 cm), dwarfed by the elongate petioles (to 1 m long); sinus narrow; Atlantic lowlands near bribrí, 100 m. ............................ A. schottianum Croat & Baker
11b. Spathes flat; peduncles more than 20 cm long, or if shorter, not dwarfed by the petioles; sinus narrow or broad; mostly 400-2,400 m.
12a. Leaf blades shallowly cordate or subcordate at base; spathe solid maroon to more commonly green and purple mottled; leaves basically lanceolate in outline.
13a. Leaf blades thin; spadix sessile, berries purple-violet becoming red; major veins of leaf reddish beneath on drying. ....A. cuspidatum Mast.
13b. Leaf blades subcoriaceous; spadix on a stipe 3-25 mm long; berries orange; major veins of leaf not reddish beneath............ A. ranchoanum Engl.
12a. Leaf blades deeply cordate at base or shallowly cordate and triangular in outline.
14a. Spathe usually dark purple-violet; stipe 0.5-2.5 cm long; stamens long-exserted ..... A. watermaliense Hort. ex L. H. Bailey
14b. Spathe usually green tinged with purple; stipe 2-6 mm long; stamens weakly exserted...... A. cotobrusii Croat & Baker
10b. Spathe white, yellow, green, or green with purple-tinged veins and/or margins.
15a. Leaf blades generally lanceolate or broadly lanceolate in outline, cordate or subcordate nasally, the lobes never overlapping each other; spathe green or green tinged with purple, never white.
16a. Petiole 4-sided; blades pendent; peduncle less than 25 cm long, much shorter than the petioles...... A. spectabile Schott
16b. Petioles terete or subterete; blades not pendent; peduncles usually more than 25 cm long, slightly shorter to longer than petioles.
17a. Spathe oblong-lanceolate; berries purple-violet to reddish-violet; major veins of leaf maroon below; blades almost always drying with a purplish tint or with purplish blotches; 400-1,700 m..... A. cuspidatum Mast.
17b. Spathe lanceolate to ovate; berries orange; major veins of leaf not maroon below; blades not drying purplish or with purplish blotches; (500)1,000-2,300 m. ....... A. ranchoanum Engl.
15b. Leaf blades generally heart-shaped in outline, with conspicuous and deep basal sinus, the lobes often overlapping each other; spathe white, green or green tinged with purple.
18a. Blades hastate, the posterior lobes usually orbicular; spadix golden yellow..... A. panduriforme Schott
18b. Blades not hastate, the posterior lobes not orbicular; spadix white, green, purple, or occasionally yellow.
19a. Plants growing at elevations above 2,000 m; flowering spadix 5-26 cm long, on a stipe 1-2.5 cm long...... A. concinnatum Schott
19b. Plants usually growing at elevations below 2,000 m; spadix various lengths, usually sessile (A. standleyi with a stipe 0.6-6 cm long.)
20a. Largest leaf blades less than 55 cm long. If not
2 la. Spadix dark purple; spathe dark green, sometimes tinged purple.
22a. Blades subcoriaceous, the basal veins coalesced 4-6 cm, the sinus much broader than deep when flattened; spathe ovate to narrow; berries pale orange. ................. A. cotobrusii Croat & Baker
22b. Blades thin, the basal veins scarcely or not at all coalesced, the sinus much deeper than broad, sometimes closed with the lobes overlapping; spathe lanceolate; berries deep red-violet. ............................ A. williamsii K. Krause
21 b. Spadix white to yellow or pale green, sometimes tinged purplish.
23a. Collective vein continuous from near base of basal lobe to apex of blade. ... A. obtusilobum Schott
23b. Collective vein formed only in upper half of blade, arising from upper basal veins, the lower basal veins running to margin.
24a. Blades ovate-triangular, the sides of the anterior lobe nearly straight; cataphylls weathering into tan fibers; spathe usually purple, at least tinged purplish; plants terrestrial. ...................... A. watermaliense Hort. Ex L. H. Bailey
24b. Blades ovate, the sides convex; cataphylls persisting more or less intact, reddish-brown; spathe pale, not tinged purplish plants epiphytic or terrestrial.
25a. Spathe 5-6(8.5) cm wide, broadly ovate. A. monteverdense Croat & Baker
25b. Spathe less than 3 cm wide, lanceolate to oblong-ovate... A. hoffmannii Schott
20b. Largest leaf blades more than 55 cm long.
26a. Leaf blades with tertiary veins sunken above, giving the blade a bullate appearance, drying pale yellow-green with a wrinkled, chartaceous character; sub-marginal collective vein usually continuous from near the base; spathe pale green, brittle; spadix pale green; berries pale green brittle white. .... A. caperatum Croat & Baker
26b. Leaf blades not appearing bullate; submarginal collective vein often beginning well above base; spathe color various, often tinged purplish; spadix white, yellow, purple, or green tinged with purple; berries orange, reddish, or purplish.
27a. Plants epiphytic.
28a. Spadix violet-purple, long tapered, to 28 cm long; blade prominently undulate. ..................... A. brownii Mast.
28b. Spadix white, pale green, greenish-yellow, or violet, short and only slightly tapered, to 18 cm long.
29a. Spathe soon reflexed; spadix cream, white or pale yellow-green; berries red, round at apex....................... A. ravenii Croat & Baker
29b. Spathe remaining close to spadix even in fruit; spadix white to violet; berries dark purple-violet with red-orange base, sharp pointed at apex. ....................... A. formosum Schott
27b. Plants terrestrial.
30a. Collective vein arising well above the middle; spathe green; spadix green when immature, soon heavily tinged violet-purple, turning yellow-brown; berries orange. ................................................... A. standleyi Croat & Baker
30b. Collective vein usually arising from one of the basal veins; spathe white, pale green or pale violet or tinged with pale violet; spadix white, yellow, lavender, or pale green tinged with lavender; berries not orange.
3 la. Blades usually drying with large, conspicuous, purplish blotches; spathe pale green becoming pale violet; spadix white to violet; berries dark purple-violet with red-orange base; common plants of the Atlantic slopes at middle elevations, sometimes seen as the dominant plant on disturbed steep banks.............................................. A. formosum Schott
31b. Blades lacking dark splotches; spathe and spadix various colors; berries not colored as above.
32a. Spadix bright yellow at anthesis, the anthers not visible (pollen oozing out in slender ribbons); leaf blades with the posterior lobes elongated, the anterior lobe usually somewhat straight along its margins; petiole rounded and smooth abaxially................... A. ochranthum C. Koch
32b. Spadix pale lavender or green tinged with lavender; anthers clearly visible, held just above the tepals; leaf blades with posterior lobes scarcely longer than broad; anterior lobe usually broadly convex along its margins; petiole subterete with seven or eight low ridges around its circumference. ........ ... A. pluricostatum Croat & Baker
7b. Species of Mexico and northwestern middle America, northwest of Río San Juan depression (Nicaragua), sometimes in El Salvador and Honduras, rarely in Nicaragua.
33a. Petioles broadly sulcate or D-shaped in cross-section, the adaxial margins often acute, sometimes merely obtuse. If Not
34a. Leaf blades merely subcordate, lacking well developed posterior lobes. If not
35a. Leaf blades with the basal veins and primary lateral veins usually reddish; Sierra de Oaxaca in northern Oaxaca...... A. subovatum Matuda
35b. Leaf blades with all veins greenish; Guerrero and southern Oaxaca to Chiapas, Guatemala, El Salvador, or Honduras.
36a. Blades less than 12 cm long; southwestern Chiapas near border with Oaxaca................ A. cerrobaulense Matuda
36b. Blades usually more than 15 cm long; Oaxaca, Chiapas, Guerrero in Mexico, Guatemala, Honduras, or El Salvador.
37a. Collective vein arising from one of the lower basal veins; posterior lobes usually longer than broad and directed prominently outward; ╚ northern Chiapas to Guatemala. ......... A. seleri Engl.
37b. Collective vein arising from the first (or second) basal vein or one of the primary lateral veins, the posterior lobes usually not longer than broad and not directed prominently outward.
38a. Blades more or less oblong, three to four times longer than broad, often broader near the base....................... A. nakamurae Matuda
38b. Blades triangular to ovate, less than three times longer than broad, broadest at base.
39a. Leaf blades with margins of the anterior lobe usually concave............ A. cerrobaulense Matuda
39b. Leaf blade with margins of the anterior lobe broadly convex.
40a. Spadix pale green; blades with the collective vein often arising from the first basal vein, frequently with a secondary collective vein extending irregularly along the margin to the apex or nearly to the apex; second basal vein merging with the margin in the upper half of the blade; Mexico, in Guerrero and southern Oaxaca and Chiapas................ A. rzedowskii Croat
40b. Spadix dark violet-purple or green tinged with violet-purple; blades with the collective vein arising from the first or second basal vein, lacking a secondary collective vein; the second basal vein often merging with the margin below the middle of the blade; Oaxaca and Chiapas, Guatemala, El Salvador╚ , and Honduras.
4 la. Leaf blades with tertiary veins obscure above (fresh); western Guatemala to northern El Salvador and western Honduras. .........A. chamulense Matuda, A, subcordatum Schott, A. subcordatum ssp. chlorocardium (Standl. & L. 0. Wms.) Croat, A. subovatum Matuda
41 b. Leaf blades with tertiary veins minutely sunk en and visible above when fresh; Oaxaca and Chiapas. :
42a. Leaf blades with tertiary veins below scarcely visible; blades subcoriaceous; occurring in "bosque pinencino" (see Flores, et al., 1971)..... A. chamulense Matuda ssp. chamulense
42b. Leaf blades with the tertiary veins clearly visible below; blades of medium thickness; occurring in "selva alta perrennifolia" ....... A. chamulense ssp. oaxacanum Croat
43a. Spathe ovate to narrowly ovate;berries orange (?); Honduras on Cerro Santa Barbara (Dept. Santa Barbara).......................... . A. subcordatum ssp. chlorocardium(Standl. & L.0. Wms.) Croat
43b. Spathe lanceolate (rarely narrowly ovate); berries bright red; western Guatemala to El Salvador and Honduras along the Continental Divide. .... A. subcordatum Schott ssp. subcordatum
Continue to next page...