3. Gaultheria LINNAEUS Sp. Pl. 1: 395 (1753). -- Type: Gaultheria procumbens L.
Brossaea LINNAEUS, Sp. Pl. 2: 1190 (1753); Gen. Pl., ed. 5, 497 (1754). -- Brossea COTHENIUS,
Disp. 11 (1790), orth. var. -- Epigaea LINNAEUS sect. Brossaea A. DE CANDOLLE,
Prodr. 7: 591 (1839). -- Type: Brossaea coccinea L.

For detailed synonymy, see LUTEYN (1995).

Reference: MIDDLETON, D. J. & C. C. WILCOCK, Chromosome counts in Gaultheria and related genera. Edinburgh J. Bot. 47(3): 303--313 (1990). -- MIDDLETON, D. J., Infrageneric classification of the genus Gaultheria L. (Ericaceae). Bot. J. Linn. Soc. 106: 229--258 (1991a). -- MIDDLETON, D. J., Ecology, reproductive biology and hybridization in Gaultheria L., Edinburgh J. Bot. 48(1): 81--89 (1991b). -- MIDDLETON, D. J., A chemotaxonomic survey of flavonoids and simple phenols in the leaves of Gaultheria L. and related genera (Ericaceae). Bot. J. Linn. Soc. 110: 313--324 (1992). -- LUTEYN, J. L., Gaultheria , in J. L. LUTEYN (ed.), Ericaceae--Part 2. The superior-ovaried genera (Monotropoideae, Pyroloideae, Rhododendroideae, and Vaccinioideae p.p.). Flora Neotrop. Monogr. 66: 384--488 (1995).

Erect terrestrial or epiphytic shrub, prostrate undershrub, or rarely small tree; indumentum of simple, unicellular or multiseriate, multicellular eglandular or gland-tipped hairs. Leaves alternate, evergreen, usually coriaceous, margin usually serrate or crenate; pinnately nerved. Inflorescence axillary, racemose or of solitary flowers, when solitary sometimes congested at the branch tips forming pseudoracemes; racemes bracteate at base, solitary flowers multibracteate at base; bracteoles 2 to several, basal, medial, or closely subtending the pedicel. Flowers 5-merous, sometimes with odor of wintergreen; aestivation imbricate; calyx articulate with pedicel, deeply lobed, usually becoming fleshy (or rarely not fleshy) and accrescent in fruit; corolla sympetalous, urceolate to campanulate or sometimes cylindric-urceolate, white to pinkish or reddish; stamen 10; filaments distinct, papillose and broadened basally, glabrous or pubescent, straight, inserted at the base of the corolla, lacking spurs; anthers dehiscing by a single apical pore, normally with 2, ascendent, terminal awns on each anther sac (these rarely inconspicuous), disintegration tissue present along the connective on the abaxial side; pollen lacking viscin threads; ovary superior or rarely partly inferior, 5-locular, the ovules 5--10 (or many); style straight; stigma truncate. Fruit a 5-valved, loculicidal capsule surrounded by the usually white or dark blue-black, slightly to conspicuously fleshy, accrescent calyx, the accessory fruit thus appearing berry-like. Chromosomes: x=11.

A genus of approximately 115 species, ranging in a somewhat circum-Pacific ring from Japan and China south through Malesia, southern Australia into Tasmania and New Zealand, and then north through South and Central America, Mexico and North America; primarily temperate or montane in tropical regions.


Key to the Species of Gaultheria
1a.
Flowers solitary in the axils of normal (or only slightly reduced) leaves.
2a.
Corolla large, 7--12 mm long, bluntly 5-angled; calyx lobes long-acuminate or narrowly long-triangular, (3-) 5--7 mm long at anthesis; leaves often conspicuously thick-coriaceous with thickened margins, essentially glabrous beneath or with scattered, eglandular, strigose hairs; stem with or without strigose hairs, or sparsely strigose; fruiting calyx white.
3a.
Repent, rhizomatous subshrubs to only a few decimeters tall; stem and twigs puberulent only, without strigose hairs; pedicel hidden by bracteoles at anthesis, glandular-setose (sometimes inconspicuously); corolla often glandular-setose along the five angles; leaves not especially thickened; S Colombia-S Ecuador
.........................................................................G. amoena
3b.
Erect shrubs, apparently 0.3--l m tall; stem and twigs puberulent and also sparsely to densely strigose; pedicel not hidden by bracteoles at anthesis, without glandular setae (or rarely with a few); corolla eglandular; leaves conspicuously thick-coriaceous.
4a.
Leaves oblong, conspicuously sharp-mucronate, concave, 1.3--2 cm long, venation obscure beneath; bracteoles caducous; ovary and style densely short-pilose; plant inflorescence strictly of solitary flowers
.................................................................G. stereophylla
4b.
Leaves elliptic-lanceolate, obtusely callose-apiculate, flat, 2--2.6 cm long, venation conspicuous beneath; bracteoles persistent; ovary sparsely short-pilose, style glabrous; plants rarely with both solitary flowers and few-flowered racemes together
.................................................................G. oreogena
2b.
Corolla smaller, 2--8 mm long, usually terete not bluntly angled; calyx lobes acute to short-acuminate, 2--4 mm long at anthesis; leaves subcoriaceous to coriaceous, not conspicuously thickened, strigose beneath with eglandular, basally-swollen (often caducous, but base remaining) hairs, or shortly glandular-setose with hairs ca 0.2--0.3 mm long, very rarely glabrous; stem or twigs usually densely strigose to hirsute; fruiting calyx blue-black or rarely white.
5a.
Erect shrubs to small tree, (0.2-) 1--3 (-10) m tall; leaves spreading to reflexed, concave (i.e., margins conspicuously incurved all around); corolla cylindric-urceolate, not noticeably inflated basally or constricted at throat; fruiting calyx usually white often flushed with pink, rarely blue-black
..........................................................................G. foliolosa
5b.
Thin- to thick-stemmed subshrubs to 0.4 (-rarely 1--2) m tall, rarely caespitose; leaves usually ascending or spreading, sometimes reflexed, basically flat, the margins not conspicuously incurved so as to make leaves appear concave; corolla urceolate to nearly subglobose, inflated at the base and very constricted at the throat; fruiting calyx usually blue-black or rarely white
..........................................................................G. vaccinioides
1b.
Flowers in axillary racemes.
6a.
Leaves tomentose-lanate beneath; inflorescences (including rachis, pedicel, calyx, and corolla) tomentose-lanate.
7a.
Leaves small, 1--3.5 x 0.4--2.8 cm, ovate, elliptic to subrotund, strongly revolute or concave (i.e., margins conspicuously incurved)
...........................................................................G. lanigera var. lanigera
7b.
Leaves larger, 3--11 x (0.6-) 1--5.5 cm, elliptic-lanceolate, to lanceolate, flat not concave
...........................................................................G. tomentosa
6b.
Leaves beneath and inflorescences glabrous or sparsely to densely pubescent but never tomentose-lanate.
8a.
Branchlets conspicuously strigose with straight, rigid, appressed hairs (these sometimes spreading); leaves strigose beneath.
9a.
Young twigs and inflorescences (including rachises, pedicel, and corollas) densely pubescent and essentially obscuring surfaces with rufous, setose to subsetose, strigose to appressed, eglandular or rarely minutely gland-tipped hairs; leaves usually densely and persistently rufous pubescent beneath (rarely with gland-tipped hairs).
10a.
Calyx glabrous; corolla glabrous to weakly short-white pilose proximally, or ferruginous-strigose only opposite the corolla lobes, sometimes weakly short-pilose proximally and weakly strigose distally, never densely strigose all over; ovary glabrous or very weakly short-pilose apically; inflorescence congested (glomerate) at anthesis with the flowers broadly overlapping; normally prostrate sub-shrubs but sometimes erect to 1 (-1.5) m tall
.................................................................G. glomerata
10b.
Calyx and corolla densely strigose-hirsute with ferruginous, subsetose, rarely glandular hairs [Note: if pubescence of twigs, rachises, pedicel, calyx, or corolla is minutely gland-tipped, then go to lead 18b]; ovary densely short-white pilose or cinereous; inflorescence not congested at anthesis the flowers widely spaced; normally erect shrubs, (0.15-) 1--3 (-5) m tall
.................................................................G. bracteata
9b.
Young twigs and inflorescences glabrous to variously pubescent with eglandular hairs, but not so densely pubescent so as to obscure surfaces; leaves merely strigose beneath.
11a.
Calyx densely strigose (rarely glabrous); corolla usually strigose at least along the angles
.................................................................G. strigosa
12a.
Leaves with margins nearly plane or only slightly incurved, broader than 10 mm, basally acute to cuneate
........................................................10a. var. strigosa
12b.
Leaves with margins tightly revolute or conspicuously incurved (curled), 5--8 mm broad, basally rounded to obtuse or acute
........................................................10b. var. revoluta
11b.
Calyx glabrous or very rarely strigose; corolla glabrous to densely strigose.
13a.
Corolla 9--12 mm long; rachis less than 2 cm long, up to 3-flowered; calyx lobes 5--7 mm long; pedicel 10 (-20) mm long
........................................................G. oreogena
13b.
Corolla 4--8 mm long; rachis greater than 2 cm long, normally 6--12-flowered; calyx lobes 2--3.2 mm long; pedicel 4--10 (-12) mm long; leaves ovate to ovate-lanceolate, basally rounded, sometimes subcordate, bullate; rachis 2--4 (-5) cm long, hirsute and also weakly to densely white puberulent; floral bracts ascending to clasping the pedicel; corolla glabrous; fruiting calyx white to white tinted pink
........................................................G. insipida
8b.
Branchlets glabrous or variously spreading pubescent, but not appressed-strigose with straight, rigid hairs; leaves glabrous or variously pubescent, but not strigose beneath.
14a.
Plants with the following combination of characters: leaves usually distinctly and prominently reticulate-veined on both surfaces, the lamina dark blackish- or reddish-punctate beneath and usually also above, the apex bluntly mucronate, the base usually acute to rounded (leaves epunctate and subcordate only in G. megalodonta ); inflorescences clustered at branch tips and conspicuously exceeding the leaves in length. [Note: If calyx and/or corolla is glandular-pubescent, or if the leaves are cordate, then go to lead 17b].
15a.
Leaves broadly ovate to suborbicular, up to 2 cm long, the base subcordate
.................................................................G. megalodonta
15b.
Leaves narrowly ovate, lanceolate, elliptic or oblong, usually longer than (1.5-) 2 cm.
16a.
Leaves conspicuously reddish- or blackish-punctate over entire surface beneath, the lamina flat, concolorous; inflorescence loose at anthesis, well-exceeding the leaves; corolla white, pilose within; 1525--3900 m elev
........................................................G. reticulata
16b.
Leaves punctate or more commonly provided with tiny glandular setae only along the veins beneath, the lamina usually bullate and concave to revolute, the upper surface much darker than the lower when dry; inflorescence congested at anthesis, barely exceeding the leaves; corolla red, glabrous within; 3250--3800 m elev
........................................................G. sclerophylla
14b.
Plants without combination of characters described above; often with calyx and/or corolla glandular pubescent; often with leaves large and basally cordate.
17a.
Young branches, leaves, rachises, and pedicel usually bearing ferruginous, subsetose, essentially eglandular (or extremely minutely glandular-tipped) hairs, usually so dense as to obscure surfaces, the hairs ascending or spreading; mature leaves usually persistently and densely hirsute beneath with ferruginous subsetose, eglandular hairs; inflorescence (rachis, pedicel, calyx, and corolla) pubescence eglandular.
18a.
Calyx glabrous; corolla glabrous to weakly short-white pilose proximally, or only ferruginous-strigose opposite the corolla lobes, sometimes weakly short-pilose proximally and weakly strigose distally, never densely strigose all over; ovary glabrous or very weakly short-pilose apically; inflorescence congested (glomerate) at anthesis with the flowers broadly overlapping; normally prostrate subshrubs but sometimes erect to 1 (-1.5) m tall
........................................................G. glomerata
18b.
Calyx and corolla densely strigose-hirsute with ferruginous, subsetose hairs; ovary densely short-white pilose or cinereous; inflorescence loose at anthesis with the flowers widely spaced; normally erect shrubs (0.15-) 1--3 (-5) m tall
........................................................G. bracteata
17b.
Young branches glabrous to variously pubescent with eglandular or glandular hairs but not so dense as to obscure surfaces; mature leaves glabrous to pubescent; inflorescence pubescence of rachis, pedicel, calyx, and corolla often glandular.
19a.
Plants glabrous or pubescent with only white, simple, eglandular hairs, without setose (multicellular, multiseriate, usually ferruginous, often glandular) hairs
........................................................G. rigida
19b.
Plants with setose (multicellular, multiseriate, usually ferruginous) hairs, which are usually (often densely) gland-tipped and also usually pilose in some part
........................................................G. erecta