Ericaceae-Neotropical Blueberries
James L. Luteyn and Paola Pedraza-Peñalosa
The New York Botanical
Garden
Family Description and Keys to the Genera
ERICACEAE A. L. de Jussieu (1789)
Vacciniaceae Lindley (1836)
Monotropaceae Nuttall (1818) nom. conserv.
Pyrolaceae Dumortier (1829) nom. conserv.
Siphonandraceae Klotzsch (1851)
Terrestrial or epiphytic shrubs, subshrubs, perennial herbs, or fleshy achlorophyllous mycotrophs, sometimes lianoid, rarely trees, sometimes rhizomatous or stoloniferous, commonly producing tannins, frequently with hypocotyl maturing as lignotuber up to 1 m diam.; indumentum of uni- to multicellular hairs or scales, these sometimes glandular. Stems terete or subterete, sometimes conspicuously winged. Leaves alternate, rarely opposite, verticillate, whorled, or lacking and then replaced by bract-like scales, sometimes "ericoid," simple, usually petiolate, exstipulate, but rarely bud scales appearing pseudostipular, newly unfolding leaves often a conspicuous red color; lamina coriaceous to membranous, evergreen to deciduous, the margin usually entire but sometimes serrulate-crenate, the venation pinnate or plinerved; leaf scars usually with a single vascular bundle scar, nodes usually with one trace and one gap. Inflorescence axillary or rarely terminal, sometimes long-pendent, racemose, paniculate, fasciculate, or flowers solitary, the parts often viscid or secretory in bud; individual flowers pedicellate or rarely sessile in axils of small or large, caducous to deciduous or persistent, floral bracts, these sometimes conspicuously glandular; pedicel usually bibracteolate; bracteoles usually persistent, small or large. Flowers mostly bisexual, but rarely functionally unisexual (more rarely plants dioecious), actinomorphic or slightly zygomorphic, mostly (3-)5(-7)-merous, typically obdiplostemonous, hypogynous or epigynous and with a typically biseriate perianth, typically without floral odors, rarely with extrafloral nectaries, with few exceptions the superior-ovaried genera pollinated by bees and the inferior-ovaried genera by hummingbirds; aestivation valvate, imbricate, or reduplicate; calyx continuous or articulate with the pedicel, synsepalous, the sepals occasionally distinct, sometimes grading into bract-like scales, rarely fleshy and accrescent to the fruit, the hypanthium when present terete or angled to winged alternate with the lobes; corolla membranous to thick-carnose, polypetalous or more commonly sympetalous, cylindric, campanulate or urceolate, terete or angled to winged opposite the lobes, sometimes basally gibbous; stamen (6-)10(-14), in 2 whorls, usually twice as many as the petals or rarely just as many, equalling the corolla in overall length or 1/2-1/3 the corolla length or sometimes long-exserted, equal with each other or alternately unequal, borne on the edge of an obscure to prominent nectariferous disc; filaments equal or unequal, usually straight or rarely S-shaped (geniculate), ligulate but sometimes basally dilated, sometimes also basally papillose, distinct or connate, with or without spurs, shorter or longer than the anther; anther inverting during development, 2-celled, equal or unequal, often distally with 2 distinct or connate tubules or terminal awns, sometimes provided with abaxial spurs; white, powdery, disintegration tissue present or lacking; thecae smooth to coarsely granular, the base rounded to apendiculate; tubules when present conical and rigid or cylindric and flexible, of equal or ca. 1/2 the diameter of the thecae, longer to shorter than the thecae; dehiscence normally introrse, but rarely extrorse or latrorse, by longitudinal or more typically by apical to subapical clefts or pores; pollen grains in tetrahedral tetrads or rarely single, sometimes with viscin threads; pistil single; ovary superior or inferior, 4-5(-10)-carpellate, usually with as many locules as carpels or with twice as many locules as carpels or rarely loculate in lower portion and 1-locular above; placentation axile, rarely intruded parietal; ovules numerous per locule or rarely solitary, anatropous to campylotropous with a single integumentary layer; style single, fluted, hollow; stigma simple but occasionally weakly lobed. Fruit a loculicidal or septicidal capsule, berry, or drupe, with a usually persistent, rarely accrescent and fleshy calyx; seeds small, ca. 1-1.5 mm long, usually numerous (1 per locule in Gaylussacia), winged or tailed (only in Bejaria), sometimes enclosed in a mucilaginous sheath, the testa thin with elongated or isodiametric cells, the endosperm fleshy, the embryo straight, usually white or sometimes green. Chromosome numbers: x=6, 8, 11, 13, 19, 23.
The family comprises ca. 110 genera with ca.
4000 species, and is cosmopolitan with the exception of Antarctica.
The following treatment of neotropical Ericaceae is conservative in that
it does not include members of the closely related Empetraceae and Epacridaceae,
included by some in a broader concept of Ericaceae (see Kron & Hills,
1991; Anderberg, 1992, 1993; Judd & Kron, 1993; Kron
& Chase, 1993; Stevens, 1995; Kron, 1996). Rhododendron
simsii Planchon is sometimes cultivated in the montane areas throughout
the Neotropics.
[Notes on using the key. The keys and descriptions below are based primarily on herbarium specimens, but in addition living (in situ), greenhouse-grown plants, material preserved in FAA or alcohol, and photographs taken from fresh, field or greenhouse-grown material. Floral measurements are taken from herbarium material at anthesis unless otherwise stated; colors when given are from fresh material observed by the author unless otherwise stated; measurements separated by the times sign (x) signify length by width, respectively; if a range of measurements is not available, the known measurement is preceeded by the abbreviation ca (about); calyx limb length includes measurement of the lobes, and anther length includes thecae and tubules.]
Key to the Genera of Neotropical Ericaceae with Superior Ovaries
1. Plants without chlorophyll, mycotrophic; pollen in monads.
2. Corolla polypetalous; sepals glabrous;
plants to 30 cm tall; fruit
opening from distal
end; floral axes eglandular, emerging from soil
in a nodding position;
pine-oak forest to N Colombia ...... Monotropa.
2. Corolla sympetalous; sepals glandular
pubescent; plants to 2 m tall;
fruit opening from
base toward apex; floral axes viscid, glandular
pubescent, emerging
from soil in an erect position; N Mexico .......
........................................................................................
Pterospora.
1. Plants with chlorophyll, autotrophic; pollen in tetrads
(or monads
in Orthilia).
3. Plants with ± herbaceous habit;
embryos undifferentiated, without
developed cotyledons.
4. Stems leafy;
inflorescence a corymb or flowers solitary;
filaments conspicously dilated at or below the middle;
stigmas sessile; capsule valves without connecting threads,
smooth at dehiscence; pollen grouped into polyads of tetrads;
Hispaniola and Mexico-Panama ................................ Chimaphila.
4. Stems scapose,
leaves clustered near the base; inflorescence a
raceme; filaments tapering gradually to base; stigmas with
long styles; capsule valves connected by cobwebby threads at
dehiscence; pollen in single tetrads or monads.
5. Racemes secund; styles straight at anthesis; stigmas
not surrounded by a collar or ring; leaves finely
serrate with acute teeth; pollen in monads; Mexico-
Guatemala .................................................................
Orthilia.
5. Racemes spiral; styles declinate at anthesis; stigmas
surrounded by a collar or ring; leaves entire or obtusely
and inconspicuously crenate; pollen as single tetrads;
Mexico-Guatemala .....................................................
Pyrola.
3. Plants shrub- or tree-like, with woody
habit; embryos well-
developed, with cotyledons.
6. Corolla usually
widely campanulate, rotate, salverform,
infundibular or tubular, polypetalous or sympetalous;
viscin threads mixed with pollen tetrads; ovary superior;
fruit a septicidal capsule.
7. Corolla polypetalous; flowers 5-7(-9)-merous.
8. Ovary smooth; stamens and style exserted at anthesis;
leaves more or less plane, not ericoid, alternate;
anther dehiscence by terminal pores; widespread in
Andes ...................................................................
Bejaria.
8. Ovary warty; stamens and style inserted at anthesis;
leaves ericoid, whorled; anther dehiscence by slits
running the entire length; endemic to Guayana
Highland ..................................................... Ledothamnus.
7. Corolla sympetalous; flowers 5-merous.
9. Corolla rotate, with 10 pouches which hold the anthers
in bud; capsule globose; Cuba ............................
Kalmia.
9. Corolla salverform, without pouches, ± zygomorphic;
capsule cylindrical; infrequently cultivated .........
................................................................. Rhododendron.
6. Corolla urceolate, cylindric-urceolate
or tubular, sympetalous;
viscin threads absent; ovary superior or inferior; fruit a
loculicidal capsule, drupe, or berry.
10. Inflorescence terminal; mesocarp of fruit fleshy either
dry or ± juicy.
11. Surface of ovary and fruit smooth; inflorescence usually
condensed; fruit dry or mealy; only found in Mexico to
W Guatemala ......................................... Arctostaphylos.
11. Surface of ovary and fruit papillate; inflorescence
usually elongate, often paniculate; fruit ± juicy.
12. Fruit a drupe, ovule 1 per locule; leaf
length/width ratio usually greater than 3; leaf
length/petiole length ratio usually greater than 10;
leaf base usually cuneate; fruit dark purple
to black at maturity (red in C. diversifolia);
Mexico to W Panama .................... Comarostaphylis.
12. Fruit a berry, ovules more than 1 per locule;
leaf length/width ratio usually less than 3; leaf
length/petiole length ratio usually less than 10;
leaf base usually rounded to truncate or slightly
cordate; fruit orange or red at maturity Mexico to
Nicaragua ................................................... Arbutus.
10. Inflorescence rarely terminal, if so then fruit a capsule.
13. Stamens with filaments usually geniculate and/or
spurred at or just below anther/filament junction;
anthers without terminal awns or tubules.
14. Capsule with ribs prominently thickened;
multicellular hairs eglandular and lepidote
(except in L. lucida); filaments spurred and
smooth to minutely papillate; Mexico &
Hispaniola ..................................................... Lyonia.
14. Capsule without ribs thickened; multicellular
hairs, when present, glandular-headed, never
lepidote; filaments spurred or not, and with
unicellular hairs.
15. Filaments clearly geniculate, without spurs;
venation of lower leaf surface very dense,
all veins ± equally prominent; 3 species in
Andes & 25 SE Brazil .......................... Agarista.
15. Filaments straight to very slightly
geniculate, spurred at anther/filament
junction; venation of lower leaf surface
not equally prominent; Cuba .................... Pieris.
13. Stamens with filaments straight; filaments never
spurred, but anthers with terminal awns or tubules.
16. Anthers extended into terminal tubules, without
white disintegration tissue on abaxial side;
fruit a berry; leaves with 1-3 pairs of marginal
glands near base; endemic to Guayana Highland ..
.................................................................... Tepuia.
16. Anthers with terminal awns, with white
disintegration tissue on abaxial side;
fruit a berry or capsule; leaves without
marginal glands as described above; widespread
in Neotropics.
17. Fruit a berry, rarely calyx becoming fleshy
at base but never surrounding the berry
......................................................... Pernettya.
17. Fruit a capsule, surrounded by the fleshy,
accrescent calyx (calyx rarely not fleshy) ...
....................................................... Gaultheria.
Key to the Genera of Neotropical Ericaceae with Inferior Ovaries
1. Stamens strongly unequal with filaments or anthers, or filaments
and
anthers alternately conspicuously unequal
(Mexico to Bolivia).
2. Filaments equal and connate over
entire length; anthers with
tubules widening
distally ..................................................... Satyria.
2. Filaments unequal, distinct or partially
connate; anthers with
sides parallel,
not widening distally.
3. Anthers
equal; stamens 1/2-1/3 as long as corolla; floral
bracts rarely large and showy but if so then early deciduous ....
....................................................................................
Orthaea.
3. Anthers
unequal; stamens as long as corolla or rarely 1/2-2/3
the corolla length; floral bracts usually large and showy,
usually persistent through anthesis .......................... Cavendishia.
1. Stamens equal with filaments and anthers of equal lengths
(rarely
anthers inconspicuously alternately unequal).
4. Anthers dehiscing by longitudinal
slits basically the length of
the thecae;
tubules rudimentary, apparently non-functional, less
that 0.8 mm
long (Panama-Costa Rica) ....................... Lateropora.
4. Anthers dehiscing by pores or slits
on the tubules and not
extending onto
thecae; tubules conspicuous, well-developed, greater
than 1 mm long.
5. Tubules dehiscing
by extrorse clefts (Guayana Highland) ...Notopora.
5. Tubules dehiscing
by introrse or latrorse clefts.
6. Tubules dehiscing by latrorse clefts (Panama-Costa Rica) ..
...............................................................................
Didonica.
6. Tubules dehiscing by introrse clefts.
7. Bracteoles located at apex of pedicel and surrounding
calyx (and sometimes lower corolla) ................ Disterigma.
7. Bracteoles located well below apex of pedicel, or if
apical then not clasping calyx.
8. Tubules elongate, thin, very graceful, about half as
wide (or less) as thecae.
9. Calyx continuous with pedicel, the pedicel not
jointed at apex.
10. Filaments distinct, dorsally pubescent with
tuft of retrorse hairs (Peru) ............ Pellegrinia.
10. Filaments distinct or connate, glabrous or
simply pilose.
11. Stamens 5-10; calyx lobes deltate to
narrowly triangular or linear,
conspicuous, at least 1 mm long
(Ecuador-N Peru) .................. Oreanthes.
11. Stamens 10; calyx lobes broadly
triangular, apiculate, equal to or
less that 1 mm long (northcentral
Venezuela, S Colombia-N Peru) ........
............................................ Semiramisia.
9. Calyx articulate with pedicel, the pedicel
conspicuously jointed at apex.
12. Corolla lobes proportionally very long, at
least 4 mm long (sometimes to half of the
overall corolla length); corolla usually
longer than 30 mm (one species only 15 mm
long), the base often ventricose
(S Colombia-N Peru) ................. Ceratostema.
12. Corolla lobes proportionally very short and
less than 2 mm long; corolla less than 30
mm long, the base not ventricose but tubular
or cylindric.
13. Dehiscence pores perfectly terminal;
filaments connate over entire length
(S Peru-N Bolivia) ............... Siphonandra.
13. Dehiscence pores oblique; filaments
distinct (Costa Rica-N Colombia,
Caribbean) ............................. Gonocalyx.
8. Tubules about as wide as thecae, or if narrower then
proportionally much shorter than thecae.
14. Thecae conspicuously papillate; tubules rigid,
elongate- to short-conical, sometimes laterally
connate or fused into one tubule; stamens often
1/3-1/2 as long as corolla.
15. Calyx turbinate, winged or angled opposite
the lobes; connective divided with a branch
extending up the dorsal side of each tubule
(Guayana Highland) ...................... Mycerinus.
15. Calyx ± cylindric, terete, angled, or
winged, but if winged then wings alternate
with lobes; connective terminating at base
of tubules.
16. Anther tubules fused into one;
staminal filaments connate; calyx
sharply angled and usually winged;
corolla angled to ribbed, rarely
terete; berry translucent white .....
.............................................. Macleania.
16. Anther tubules two, distinct or
laterally connate; staminal filaments
distinct (very rarely connate); calyx
terete; corolla terete; berry blue-
black or green, never translucent white.
17. Corolla subglobose, broadly
urceolate, or cylindric-subglobose
to cylindric-urceolate, usually
< 10 (-14) mm long ....... Psammisia.
17. Corolla cylindric to cylindric-
urceolate, usually elongate and
> 14 mm long.
18. Anthers (sometimes alternate
ones) bearing horn-like spurs
(sometimes inconspicuous)
along connective, if spurless
then corolla conspicuously
and abruptly constricted once
or twice at or below the
middle; anther tubules 2,
distinct or connate in lower
half ......................... Psammisia.
18. Anthers without spurs;
corolla always gradually
narrowing distally not
abruptly constricted;
anther tubules 2, laterally
connate sometimes to the tip
................................ Macleania.
14. Thecae smooth to minutely papillate; tubules
flexible, cylindric, elongate to short;
stamens usually as long as corolla, rarely half
as long (Anthopteropsis).
19. Calyx articulate with pedicel, the pedicel
jointed at apex (rarely continuous in 3
spp. of Thibaudia).
20. Corolla 3-4 mm long; calyx conspicuously
winged.
21. Corolla tube distally conspicuously
spurred opposite the lobes (Costa
Rica) ................................... Utleya.
21. Corolla terete, not spurred
distally (Colombia-Ecuador) .....
................................ Themistoclesia.
20. Corolla greater than 7 mm long, never
spurred; calyx usually terete (rarely
winged in Plutarchia, Anthopteropsis
and 1 Vaccinium from Guayana Highland).
22. Corolla strongly and conspicuously
winged; inflorescence
cauliflorous, paniculate (Pacific
coastal Colombia) ........... Thibaudia.
22. Corolla terete to angled, rarely
very narrowly but inconspicuously
winged; inflorescence usually
axillary and racemose, but if
paniculate and ramiflorous then
leaves greater than 17 cm long.
23. Corolla urceolate to
campanulate, 7-12 mm long
(but 1 species from Guayana
Highland elongate-tubular,
17-22 mm), normally of thin
texture and membranaceous,
the lobes imbricate;
filaments proportionally
long with regards to anther
length
24. Ovary with few to numerous
ovules in each of the 5(-10)
locules; fruit a many-seeded
berry ...................... Vaccinium.
24. Ovary with a single ovule in
each of the 10 locules; fruit
a drupe with 10 pyrenes ....
........................... Gaylussacia.
23. Corolla elongate-tubular,
(8-)10 mm but usually longer,
normally carnose or
coriaceous, the lobes
valvate; filamants
proportionally short and
inconspicuous with regard to
anthers.
25. Tubules usually 2-5
times longer than thecae;
leaves often opposite;
filaments rarely
alternately unequal;
páramos (Colombia-N
Ecuador) ................. Plutarchia.
25. Tubules usually about
equalling (rarely
shorter than) thecae;
leaves alternate;
filaments equal.
26. Calyx conspicuously
winged with wings
longer than lobes;
anther connectives
alternately spurred;
stamens about half
as long as corolla
(Panama) ...........
................... Anthopteropsis.
26. Calyx terete or
rarely angled;
anther connectives
unspurred; stamens
equalling corolla
(Costa Rica-Bolivia)
............................ Thibaudia.
19. Calyx continuous with pedicel, the pedicel
not jointed at apex.
27. Calyx conspicuously winged (rarely
strongly angled and then corolla winged);
corolla conspicuously to narrowly winged
or rarely sharply angled (terete in two
species of Themistoclesia).
28. Corolla conspicuously to narrowly
winged or rarely sharply angled,
7-20 mm long ................. Anthopterus.
28. Corolla terete, 3-4.5 mm long .....
.................................... Themistoclesia.
27. Calyx terete to angled but not winged;
corolla terete.
29. Calyx angled.
30. Calyx angled opposite the
lobes (Bolivia) ................. Polyclita.
30. Calyx angled alternate with
the lobes.
31. Leaves linear, 1-nerved
(Bolivia) ...................... Rusbya.
31. Leaves not linear,
multinerved (Costa Rica-
Peru) ............... Themistoclesia.
29. Calyx terete.
32. Corollas usually large,
carnose to coriaceous, (10-)
14 mm or more long; seeds
with white embryos.
33. Leaves large, greater
than 8 cm long, tubules
about equal to thecae
or not more than 2 times
as long; flowers
racemose; stamens equal
in length (Costa Rica-
Bolivia) .................. Thibaudia.
33. Leaves small, less than
3 cm long; tubules 2-5
times longer than thecae;
flowers 1-3, fasciculate;
stamens often slightly
dimorphic (Peru-Bolivia)
...................... Demosthenesia.
32. Corollas small, thin-
membranaceous, up to 10 mm
long, but if longer then
filaments proportionally much
longer than anthers; seeds
with green embryos.
34. Flowers 1-2 per axil;
pedicels usually
relatively long and thin,
filiform, cernuous;
filaments usually longer
than anthers (Mexico-
Bolivia, Hispaniola) ....
................... Sphyrospermum.
34. Flowers usually in few-
to many-flowered
fascicles or racemes,
rarely solitary;
pedicels slender but not
properly cernuous;
filaments usually shorter
than anthers (Venezuela-
Bolivia) .............. Diogenesia.