James L. Luteyn and Paola Pedraza-Peñalosa
The New York Botanical Garden
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Agarista D. Don ex G. Don (Ericaceae, Vaccinioideae, Andromedeae) includes 31 species of trees and shrubs and occurs in both Africa (including Madagascar) and the Americas. Agarista is closely related to Craibiodendron, Lyonia, and Pieris (Stevens, 1970, 1971; Judd, 1979, 1984). The African taxa have often been treated as the genus Agauria, and the American species as a section of the eastern Asian-North American genus Leucothöe (Sleumer, 1938, 1959; Judd, 1984). Agarista, however, is considered here to be a monophyletic group based on the apomorphy of densely reticulate-veined leaves that are usually revolute in bud (Judd, 1979, 1984). The American species of Agarista were monographed by Judd (1984, 1995a; see also Sleumer, 1959, as Leucothöe), and the present floristic treatment has been modified from these recent revisions. |
George Don described the genus Agarista in 1834 and included several South American and African taxa (which had up to this point usually been considered species of Andromeda). His circumscription is essentially that employed here and by Judd (1984). He included in this genus evergreen shrubs with reticulate-veined, entire-margined leaves, racemose inflorescences, flowers with cylindrical/urceolate corollas, stamens lacking spurs, and loculicidal capsules. Judd (1979, 1984) in a phenetic and cladistic study of certain genera of Andromedeae concluded that the American and African species of this complex form a phenetic and phylogenetic unit and should be recognized as a single genus: Agarista. Thus, the generic delimitation adopted by Judd (1984) and employed in this treatment is essentially that of G. Don (1834). Judd (1984) placed the American species of Agarista in section Agarista and the African species in section Agauria.
Characters most useful in species delimitation in Agarista include: 1) leaf vernation, size, shape, apex and base types, petiole length, and extent to which the margin is revolute, 2) inflorescence length, 3) unicellular indumentum of the abaxial leaf surface and of the inflorescence axes and other reproductive structures (especially calyx, corolla, and ovary), 4) calyx length and, to a lesser extent, corolla color and length, 5) placenta position (in fruit), and 6) seed length.
The genus is not of economic importance; a few species are occasionally cultivated as ornamentals. Several Brazilian species, especially in very diverse Minas Gerais region, have very limited geographical ranges and are endangered due to habitat destruction. Species of special concern include: A. angustissima, A. duartei, A. ericoides, A. organensis, and A. virgata. Agarista subcordata and A. bracamorensis likely are endangered as well; the latter as not been collected in ca. 170 years and may be extinct. The recently described Mexican species, A. villarrealanais very rare being limited to the Sierra de Cuale, in Jalisco.
AGARISTA D. Don ex G. Don, Gen. hist. 3: 837. 1834. Leucothöe D. Don sect. Agastia A. P. de Candolle, Prodr. 7: 603. 1839. Leucothöe D. Don subgen. Agarista (D. Don ex G. Don) Drude in Engler &
Prantl, Nat. Pflanzenfam. IV. 1: 42. 1889; Meissner, Fl. brasil.
7: 154-166. 1863; Sleumer, Bot. Jahrb. Syst. 69: 374-393.
1938; Sleumer, Bot. Jahrb. Syst. 78: 435-480. 1959; Judd,
J. Arnold Arbor. 65: 255-342; Judd, Fl. Neotrop. Monogr. 66: 295-344.
1995. Lectotype species. Agarista nummularia (Chamisso &
Schlechtendal) G. Don.
Leucothöe D. Don sect. Agauria A. P. de Candolle, Prodr. 7: 602. 1839. Agauria (A. P. de Candolle) J. D. Hooker in Bentham & Hooker, Gen. pl. 2: 586. 1876. Lectotype species. Agauria salicifolia (Commerson ex Lamarck) J. D. Hooker [=Agarista salicifolia (Commerson ex Lamarck) G. Don].Amechania A. P. de Candolle, Prodr. 7: 578. 1839. Lectotype species. Amechania subcanescens A. P. de Candolle [=Agarista chlorantha (Chamisso) G. Don].
Agarista D. Don ex G. Don sect. Leucothoides Niedenzu, Bot. Jahrb. Syst. 11: 186. 1890. Lectotype species. Agarista serrulata (Chamisso) G. Don [=Agarista chlorantha (Chamisso) G. Don].
Evergreen (rhizomatous) shrubs or trees
to 20 m, with longitudinally furrowed bark and terete to slightly angled
branches; indumentum of unicellular hairs and often multicellular,
multiseriate, long-stalked, gland-headed hairs; buds with 2 to 4
(to 6) imbricate scales. Leaves alternate (to subopposite or nearly
3-whorled at some nodes), petiolate; blades revolute (convolute)
in bud, coriaceous, frequently with gland-headed hairs on midvein or along
margin (also on lamina), often with unicellular hairs on midvein and sometimes
densely covering abaxial surface [sometimes papillose abaxially];
margin entire or undulate, to obscurely to clearly serrate, or serrulate/ciliate
due to presence of gland-headed hairs; venation reticulodromous, the vein
reticulum rather dense and with all orders more or less equally prominent.
Inflorescences resting within bud with meiosis probably occurring after
emergence, axillary or terminal racemes or panicles; floral bracts
solitary, small (to large and foliaceous); pedicels with 2 (several)
bracteoles at or near base to near midpoint. Flowers perfect, 5-merous,
usually fragrant; calyx of imbricate lobes, articulate with pedicel,
persistent in fruit; corolla cylindrical to urceolate, with short,
imbricate lobes, (greenish) white to red, glabrous to densely covered with
unicellular hairs abaxially, glabrous adaxially; stamens 10 in 2
whorls, inserted at base of corolla, included; filaments flattened,
somewhat expanded near base, geniculate, with long unicellular hairs, lacking
spurlike appendages; anthers more or less ovoid, minutely papillose
to nearly smooth, lacking apical awns, dehiscing by large, introrse-terminal,
elliptic pores, with white line or triangular patch of disintegration tissue
on back of each lobe near apex; ovary 5-locular, glabrous to densely
covered with unicellular hairs (with few gland-headed hairs), placentae
subapical to central [basal], slightly bilobed; nectariferous disc
an enlargment of base of ovary wall, variously developed and lobed;
style columnar, slightly swollen [not swollen] near apex, straight, slightly
to strongly impressed into apex of ovary and usually slightly exserted;
stigma truncate to capitate, obscurely lobed, minutely papillose.
Capsules erect, with sutures unthickened (or very slightly thickened near
apex), not separating from valves at dehiscence (margins of valves whitish);
placentae persistent on columella; seeds very small, brown, scobiform,
the testa thin, composed of a single layer of much elongated, thin-walled
cells; chrmomsome number: 2n=24.
A genus of 31 species occurring in South America --SE Brazil (from Bahia and Goiás south to Rio Grande do Sul), Uruguay, N Argentina, and Paraguay, along Andes from NW Argentina, Bolivia, and N Peru to Colombia, mountains of S Venezuela and adjacent Brazil (Pará); Central and North America--mountains of El Salvador and Honduras north to Mexico (Hidalgo, México, Jalisco), and on United States Atlantic Coastal Plain (from Florida to South Carolina); see Judd (1984). Also in central Africa, Madagascar, Réunion, and Mauritius (Sleumer, 1938).
Key to Neotropical Species Back to Top
[Notes on key measurements and terminology.
All measurements (except plant height, which was taken from information
included on specimen labels) included in the descriptions of species have
been taken directly from dried herbarium material. The width of the
calyx lobes was measured midway between the apex and the point where they
join the adjacent lobes; the width of all other structures was measured
at the widest point. The values for inflorescence length refer to
the range of variation in the longest inflorescence per specimen (and were
determined by surveying total available herbarium material). As used
here, "glabrous" and "pubescent" refer to the presence or absence of unicellular
hairs; the presence, distribution, and density of multicellular,
gland-headed hairs are described separately. Leaves are alternate
unless otherwise indicated.]
1. Leaves moderately to strongly adaxially folded.
2. Leaves 0.6-2.5(-3) cm wide, narrowly
to widely ovate,
petiole 10-45
mm long ................................. A.
glaberrima.
2. Leaves 0.1-0.5 cm wide, ±
linear, petiole 2-15(-20) mm
long.
3. Stems glabrous; inflorescences
axillary or terminal
racemes
or panicles to 2-6 cm long; leaves (1.7-)
3-9 cm
long ............................................. A.
angustissima.
3. Stems glabrous to densely pubescent;
inflorescences
axillary
racemes to 0.3-1.5 cm long; leaves 1.2-3.7
(-4) cm
long .................................................... A.
duartei.
1. Leaves plane to strongly revolute, always revolute in
bud.
4. Petiole slender, flexuous, elongate,
6-40 mm long.
5. Inflorescence
axis glabrous; capsules 4-8 x 6-8 mm;
leaves often slightly adaxially folded ........ A.
glaberrima.
5. Inflorescence
axis moderately to densely pubescent;
capsules 3-5 x 4-6.5 mm; leaves ± flat.
6. Leaves ovate; inflorescence rachis with whitish
hairs .................................................. A.
boliviensis.
6. Leaves oblong to ovate; inflorescence rachis
with ferrugineous hairs .................. A.
eucalyptoides.
4. Petiole stout and/or short, not flexuous,
0.5-15(-18)
mm long.
7. Leaves
0.4-2.5(-3.5) x 0.1-1.6(-2) cm.
8. Leaf margin ± plane (to very slightly
revolute, especially near base), blade ±
flat.
9. Inflorescence rachis glabrous.
10. Leaf blade with length/width quotient
> 1.8; corolla 7.5-13 mm long;
filaments 5-6.5 mm long ............ A.
pulchella.
10. Leaf blade with length/width quotient
< 1.8; corolla 6-8.5 mm long; filaments
3.5-5 mm long.
11. Multicellular, gland-headed hairs
present on leaves and twigs;
branches rigidly ascending and wand-
like, with internodes usually only
ca. 0.5 cm long; leaves 0.4-1.3 cm
wide ..................................... A.
virgata.
11. Multicellular, gland-headed hairs
lacking; plants ± widely to erectly
branched, with internodes to 0.5-2
cm long; leaves 0.8-2.2 cm wide .......
............................................ A.
pulchra.
9. Inflorescence rachis sparsely to densely
pubescent.
12. Abaxial leaf surface ± densely
pubescent .............................. A.
subrotunda.
12. Abaxial leaf surface ± glabrous (but
often with few unicellular hairs on
midvein).
13. Sepals 2.5-5 mm long ........ A.
nummularia.
13. Sepals 0.8-2.7 mm long.
14. Capsules with ± central
placentae.
15. Inflorescence rachis to 0.5-
1.5 (-2.5) cm long; leaf
blade with length/width
quotient usually > 3, cuneate
to truncate at base ... A.
minensis.
15. Inflorescence rachis to 2-7
(-12) cm long; leaf blade with
length/width quotient usually
< 3, cordate to rounded at
base ......................... A.
pulchella.
14. Capsules with ± subapical
placentae.
16. Hairs of inflorescence rachis
to (0.15-)0.2-0.4 mm long,
straight to curved ...... A.
albiflora.
16. Hairs of inflorescence rachis
to 0.05-0.15(-0.17) mm long,
curved.
17. Leaves cuneate to rounded
at base; inflorescence
rachis usually 1.5-3.5 cm
long ............... A.
niederleinii.
17. Most leaves at least
slightly cordate at base;
inflorescence rachis
usually 2-28 cm long.
18. Stems moderately to
densely pubescent;
inflorescence rachis to
(1.5-)2-5.5 cm long ....
.................. A.
pulchella.
18. Stems glabrous to
sparsely pubescent;
inflorescence rachis to
4-28 cm long.
19. Petioles 1-2.5 mm
long, lamina lacking
prominent abaxial
glands along midvein,
margin usually at
least slightly
undulate and
frequently very
slightly revolute;
Peru ... A. subcordata.
19. Petioles 1.5-6 mm
long, lamina without
above combination of
characters, with or
without conspicuous
abaxial glands,
margin usually plane;
SE Brazil.
20. Leaf blades with
length/width
quotient (1.3-)
1.8-2.5, prominent
abaxial glands
present along mid-
vein; inflores-
cence rachis
moderately to
densely pubescent.
......... A. coriifolia.
20. Leaf blades with
length/width
quotient 0.9-1.7,
usually lacking
prominent abaxial
glands; inflores-
cence rachis very
sparsely to
moderately pubes-
cent ..... A. pulchra.
8. Leaf margin slightly to strongly revolute
and/or whole blade slightly to clearly
abaxially curved.
21. Corolla very sparsely to densely
pubescent abaxially.
22. Calyx lobes 2-5.5 mm long; corolla
abaxially sparsely to densely
pubescent; seeds ca. 0.6-1.5 mm long;
erect shrub 1-2.5 m tall, of inland
habitats ............................................. A.
hispidula.
22. Calyx lobes 0.9-1.6 mm long; corolla
abaxially with very few unicellular
hairs near apex (or glabrous); seeds
ca. 2-3.5 mm long; shrub or gnarled
tree to 3(-6) m tall, of coastal scrub.
.......................................................... A.
revoluta.
21. Corolla glabrous abaxially.
23. Capsules with ± central placentae;
leaves 0.1-0.25 cm wide .................. A.
ericoides.
23. Capsules with ± subapical placentae;
leaves 0.15-2.2 cm wide.
24. Flowers solitary in leaf axils or
borne on fascicle-like racemes to
1.5 cm long; plants lacking gland-
headed hairs; calyx lobes 1-2 mm
long; Serra dos Orgãos .......... A.
organensis.
24. Flowers in axillary (terminal)
racemes to (1-)1.5-9.5 cm long;
plants with or without gland-
headed hairs; calyx lobes variable;
not from the Serra dos Orgãos.
25. Calyx lobes 2.5-5.5 mm long;
corolla 7-11.5 mm long; leaves
clearly cordate at base;
inflorescence rachis and pedicels
with or without gland-headed
hairs ............................... A.
chlorantha.
25. Calyx lobes 0.5-2.7 mm long;
corolla 4.5-9 mm long; leaves
cuneate to rounded or slightly
cordate at base; inflorescence
rachis and pedicels lacking
gland-headed hairs.
26. Leaves 0.4-2.2 cm wide, with
margins revolute frequently to
varying degrees even within
single plant; valves of mature
capsules frequently ± whitish
bordered; capsules ovoid to
globose or subglobose; coastal
"restingas" ................. A.
revoluta.
26. Leaves 0.25-1.3 cm wide, with
margins more uniformly
revolute within single plant;
valves of capsules not
obviously bordered; capsules
subglobose or short-ovoid;
mountainous habitats.
27. Capsules robust, 4.5-6.5 x
6.5-8.5 mm; inflorescence
rachis to 1.5-3.5(-4.5) cm
long; SE Brazil ..............
.................... A.
niederleinii.
27. Capsules smaller, 4-5 x
4.5-6 mm; inflorescence
rachis to 5-10 cm long;
Peru.
28. Leaves 0.25-0.7 cm
wide, 0.8-1.5 cm long,
margin ± strongly
revolute; pedicels 1.5-3
mm long .. A.
bracamorensis.
28. Leaves 0.6-1.3 cm wide,
1.2-3.1 cm long, margin
plane to slightly revo-
lute; pedicels 3.5-7 mm
long ......... A.
subcordata.
7. Leaves
1.5-11.2 x 0.3-4.5(-5) cm.
29. Lamina with ± strongly revolute margins,
whole surface slightly to strongly abaxially
curved.
30. Inflorescence rachis to 0.7-1.5 cm long;
leaf apex short-acuminate to elongate-
mucronate, mucro usually to 1.5-2 mm
long; Venezuela (Bolívar, T.F. Amazonas),
Brazil (Pará and Mato Grosso) ............... A.
duckei.
30. Inflorescence rachis to 1.5-10 cm long;
leaf apex acute- to rounded-mucronate,
mucro usually to only 1 mm long.
31. Leaf apex obtuse- to retuse-mucronate;
valves of mature capsules ± white
bordered; coastal "restingas," E Brazil
..................................................... A.
revoluta.
31. Leaf apex acute- to obtuse-mucronate;
valves of capsules ± unbordered;
mountainous habitats, Andes from
Venezuela to Peru ......................... A.
albiflora.
29. Lamina with plane to only very slightly
revolute margin, surface ± flat.
32. Abaxial leaf surface ± densely covered
with unicellular hairs, at least parts of
surface completely obscured.
33. Capsules with ± central placentae;
seeds 0.9-1.8 mm long; pith ± solid to
hollow, often with very sparse, thin
septa; Paraguay, Argentina .............
............................................ A.
paraguayensis.
33. Capsules with ± subapical placentae;
seeds 1.3-3 mm long; pith ± solid to
irregularly chambered, the septa thick
to thin, closely spaced.
34. Inflorescence rachis to 0.5-2(-4) cm
long; leaves ovate, apex acuminate;
Mexico and C America ........ A.
mexicana.
34. Inflorescence rachis to 4-7 cm long;
leaves ovate to elliptic or oblong,
apex acute- to retuse-mucronate; E
Brazil.
35. Leaf base cordate; pedicels 5-
12.5 mm long ............ A.
subrotunda.
35. Leaf base rounded to cuneate;
pedicels 3-7 mm long ...........
.............................. A.
chapadensis.
32. Abaxial leaf surface lacking unicellular
hairs to ± sparsely pubescent, surface not
obscured.
36. Capsules with ± central placentae;
seeds 0.5-1.5 mm long.
37. Corolla very sparsely to sparsely
pubescent (glabrous); pith ± solid
to hollow or with very sparse,
thin septa; Paraguay, Argentina .....
................................... A.
paraguayensis.
37. Corolla glabrous; pith ± solid to
irregularly or clearly chambered,
the septa thin to thick, ± closely
spaced; SE Brazil.
38. Inflorescence rachis to 0.5-1.5
cm long; leaves 0.3-1(-1.7) cm
wide, length/width quotient
usually >3, ± straight sided,
base cuneate to truncate, apex
rounded- to bluntly acute-
mucronate (never narrowly acute),
petiole 2-6 mm long ..... A.
minensis.
38. Inflorescence rachis to 2-12 cm
long; leaves various, but without
above combination of characters.
39. Leaves ovate, 1.2-4.5(-5)
cm long, base ± cordate,
petiole 1.5-5 mm long.
40. Lamina with abaxial glands
lacking or very incon-
spicuous along midvein near
base, thinly coriaceous and
flexible when dry; Paraná,
Santa Catarina, São Paulo.
....................... A.
pulchella.
40. Lamina with prominent
abaxial glands along mid-
vein near base, thickly
coriaceous and quite in-
flexible when dry; Minas
Gerais.
41. Infloresence rachis ±
moderately pubescent ..
................. A.
coriifolia.
41. Inflorescence rachis
glabrous ..... A.
pulchra.
39. Leaves ovate to elliptic or
oblong, 2-12.5 cm long, base
cuneate to slightly cordate,
petiole 2-11.5 mm long ........
.............................. A.
oleifolia.
36. Capsules with ± subapical placentae;
seeds 1-3.2 mm long.
42. Inflorescence rachis usually
moderately to densely covered with
ferrugineous unicellular hairs .....
..................................... A.
eucalyptoides.
42. Inflorescence rachis glabrous to
densely pubescent, but hairs not
ferrugineous.
43. Inflorescence rachis to 0.5-3.5
(-4) mm long.
44. Leaves uniformly ovate, apex
acuminate (to acute).
45. Shrubs to 0.5 m tall,
rhizomatous; corolla red ..
...................... A.
villarrealana.
45. Shrubs to 3-20 m tall,
non-rhizomatous; corolla
white.
46. Leaf margin
conspicuously crisped/
undulate .... A.
boliviensis.
46. Leaf entire to serrate,
margin not conspicuously
crisped/undulate.
47. Capsules (3-)4-6 mm
long, with thick-
ened, ± warty/rough-
ened walls; SE
Brazil ...... A. uleana.
47. Capsules 3-4.5 mm
long, with thin, ±
smooth walls; N &
C America, and N
Argentina.
48. Ovary very
sparsely to
densely
pubescent; pith
nonseptate to
septate.
49. Filaments 3.5-
4.5 mm long;
inflorescence
rachis to 1-4
cm long;
corolla
glabrous; N
Argentina ...
. A. boliviensis.
49. Filaments 4.5-
6 mm long; in-
inflorescence
rachis usually
to only 0.5-2.5
cm long; corolla
glabrous to
sparsely pubes-
cent; Mexico &
C America ....
.... A. mexicana.
48. Ovary glabrous;
pith always
clearly septate.
50. Calyx glabrous
on abaxial
surface;
pedicels
glabrous;
corolla 8.5-13
mm long; leaves
entire; bark
furrowed, corky;
Mexico ........
..... A. sleumeri.
50. Calyx sparsely
to moderately
pubescent on
abaxial sur-
face; pedicels
sparsely to
moderately
pubescent;
corolla 6.5-
9.5 mm long;
leaves entire
to serrate;
bark very
shallowly fur-
rowed, not
corky; SE
United States.
[A. populifolia.]
44. Leaves of single plant
varying from ovate to elliptic
or oblong (obovate), apex
acute- or rounded-mucronate
to acuminate.
51. Capsules roughened/
warty; leaves with apex
acute- or rounded-mucronate
to acuminate, margins
convex-curved to ± straight
and parallel when viewed
from above; SE Brazil.
52. Leaves ± ovate to
elliptic, margin very
slightly revolute from
base to near apex;
Guanabara, Rio de
Janeiro ................ A.
uleana.
52. Leaves ovate to
elliptic/oblong,
at least a few per
plant ± parallel sided,
margin plane to very
slightly revolute at
base only; Rio Grande
do Sul to Paraná ......
..................... A.
niederleinii.
51. Capsules ± smooth; leaves
with apex elongate-
mucronate to short-
acuminate, margin convex-
curved when viewed from
above; Brazil (Mato Grosso,
Pará) & Venezuela (Bolívar,
Amazonas) ............... A.
duckei.
43. Inflorescence axis to 3-15 cm long.
53. Inflorescence rachis with
hairs to 0.15-0.4 mm long,
straight to curved; calyx
lobes 0.7-1.8 mm long; corolla
(3.7-)4-9 mm long; leaves
thinly coriaceous, flexible
when dry; Andes from Venezuela
to Peru ......................... A.
albiflora.
53. Inflorescence rachis glabrous
or with hairs to 0.05-0.15 mm
long, curved; calyx lobes 1-
2.7 mm long; corolla 6.5-11 mm
long; leaves thickly
coriaceous, rather inflexible
when dry; SE Brazil ..... A.
coriifolia.
This is an electronic version of the taxonomic treatment of the neotropical species of Agarista (Ericaceae) by Walter S. Judd (In: Ericaceae--Part II. The Superior-Ovaried Genera (Monotropoideae, Pyroloideae, Rhododendroideae, and Vaccinioideae p.p.). The full treatment including specimen citations may be see in Flora Neotropica Monograph 66: 295-344 (Judd, 1995a). This on-line synthesis is published with permission of The New York Botanical Garden and Walter S. Judd.