Gaultheria

Fritsch, Peter W., Armstrong, Kate E., Aung, Mu Mu, Fujikawa, Kazumi & Lu, Lu, 2023, Gaultheria (Ericaceae) of Myanmar: an updated species list for the country, a new species, and a new species combination, Phytotaxa 595 (1), pp. 37-61 : 54-56

Key to the species of Gaultheria from Myanmar

1. Inflorescences always 1-flowered; larger leaf blades 0.15–1.5 × 0.1–0.9 cm (0.6–2.1 × 0.5–1.9 cm in G. nummularioides ).

2. Bracteoles more than 2, not apical; corolla inside pubescent; filaments pubescent ................................. G. nummularioides

2. Bracteoles 2, apical; corolla and filaments glabrous.

3. Branchlets long trailing; calyx lobes and corolla lobes 4; calyx at fruiting red ............................. G. suborbicularis

3. Branchlets not long trailing; calyx lobes and corolla lobes 5 (rarely 4 in G. hypochlora and G. sinensis ); calyx at fruiting blue, white, or rarely pinkish white or pink.

4. Calyx and often bracteoles ciliolate at apex (cilia often visible on fruiting calyx lobes as well).

5. Longer leaf blades elliptic to slightly obovate, 3.1–5.7 mm wide, abaxial setae 1 to ca. 23 situated along or near midvein, midvein thickened abaxially immediately below apical gland; flowering calyx red or green flushed red; fruiting calyx crateriform to broadly cupuliform ....... G. ciliisepala

5. Longer leaf blades obovate to broadly obovate, 4.5–7.2 mm wide, abaxial setae 4 to ca. 100 situated along midvein and usually spread across surface often to near margin, midvein usually not thickened or occasionally thickened abaxially immediately below apical gland; flowering calyx green; fruiting calyx broadly turbinate or rarely broadly cupuliform.......................... G. hypochlora

4. Calyx and bracteoles eciliolate.

6. Fruiting calyx white.

7. Leaf blades 2–3 mm long; overwintering flower bud pedicels 0.1–0.2 mm long; capsule maroon ....................................................................................... G. bryoides

7. Leaf blades 6–14 mm long; overwintering flower bud pedicels 0.9–2.4 mm long; capsule green (color unknown in G. thymifolia ).

8. Corolla urceolate, lobes 0.5–0.9 × 0.4–0.9 mm; anther cells 0.8–1.0 mm long, awns 0.5–0.6 mm long; style 2.5–3.0 mm long; fruiting calyx 8–11 × 7–8 mm ................................................................................ G. cardiosepala

8. Corolla campanulate, lobes 1–3 × 1–2 mm; anther cells 0.4–0.7 mm long, awns 0.2–0.3 mm long; style ca. 1.5 mm long; fruiting calyx 6–8 × 8–11 mm ............................................................................................ G. thymifolia

6. Fruiting calyx blue.

9. Fruiting calyx closed.

10. Fruiting pedicels 9–17 mm long.................. G. dolichopoda

10. Fruiting pedicels 2–4 mm long....................... G. crassifolia

9. Fruiting calyx open.

11. Leaf blade marginal setae 0.1–0.4 mm long ............ ................................................................ G. sinensis

11. Leaf blade marginal setae 0.5–1.3 mm long.

12. Leaf blades always glabrous abaxially, marginal teeth (setae) 3 to 8 per side; overwintering flower bud pedicels 1.1–1.5 mm long....................................... G. minuta

12. At least some leaf blades abaxially with one or more setae along midvein, marginal teeth (setae) 8 to 14 per side; overwintering flower bud pedicels 1.7–3.8 mm long ......... ................................................... G. obovata

1. Some or all inflorescences with more than one flower; larger leaf blades 1.4–17.0 × 0.7–9.7 cm.

13. At least one secondary vein on each side of leaf blade arising at or near base of blade and extending to apex or nearly so.

14. Leaf blade secondary veins 2 to 4 on each side of midvein, margin with 10 to 25 teeth per side; rachis and pedicels hirsute or lanate; bracteoles apical; corolla urceolate, villous inside ........................................................ G. discolor

14. Leaf blade secondary veins 1 or 2 on each side of midvein, margin with 25 to many teeth per side; rachis and pedicels glabrous or puberulent; bracteoles basal; corolla campanulate, glabrous ................................. G. dumicola

13. Secondary veins all arising along midvein with proximal veins becoming faint or anastomosing before reaching apex.

15. Bracteoles apical or subapical along pedicel.

16. Leaf blades lanceolate, rounded to truncate or cordate at base; corolla campanulate........................ ..................................................................................................................................... G. leucocarpa

16. Leaf blades elliptic to obovate or oblanceolate, cuneate to subrounded at base; corolla urceolate to subglobose.

17. Branchlets glabrous or occasionally sparsely setulose (or puberulent or both); corolla 3.5– 5.0 mm long; stamens 10; filaments 1.5–2.0 mm long, sparsely pilose.... G. fragrantissima

17. Branchlets densely setose and puberulent; corolla 2.0– 3.5 mm long; stamens (2 to)5(to 8); filaments 0.5–1.3 mm long, glabrous.............................................................. G. semi-infera

15. Bracteoles ± medial along pedicel.

18. Leaf blades abaxially patent- to erect-villous-hirsute; bracts rhombic-lanceolate to linear-lanceolate, apex long-recurved-acuminate; calyx lobes acuminate at apex .... ................................................................................................................... G. wardii

18. Leaf blades abaxially glandular-punctate or appressed to ascending-setose or stipitate-glandular; bracts narrowly deltoid, broadly elliptic, ovate, or suborbicular, apex rounded to short-acuminate; calyx lobes obtuse to sharply acute at apex.

19. Leaf margins with ca. 40 to 90 teeth per side.

20. Stems narrowly 3-winged; petioles 2–3 mm long; base of leaf blade shallowly cordate; inflorescence peduncle and rachis white-villous, trichomes up to ca. 1 mm long; bracts abaxially sericeous-villous to -hirsute at least on basal half; ... bracteoles 2.8–3.2 mm long; calyx lobes 3.0–3.9 × 1.9–2.4 mm ............................................ G. insignis

20. Stems rounded to angulate; petioles 4–12 mm long; base of leaf blade cuneate to rounded; inflorescence peduncle and rachis whitepubescent, trichomes up to ca. 0.2 mm long; bracts abaxially glabrous; bracteoles 1.5–2.0 mm long; calyx lobes 1.5–2.8 × 1.3– 1.8 mm ....................................................................... G. griffithiana

19. Leaf margins with ca. 8 to 40 (to 47 in some G. stapfiana ) teeth per side. 21. Petioles slightly winged, 8–22 mm long; bracts keeled, 1.3–2.3 mm long................................... G. natmataungensis

21. Petioles not winged, 1–8(–10) mm long; bracts not keeled, 2.3–6 mm long.

22. Shrublets 0.03–0.50 m tall; leaf blades 1.4–3.7 cm long, abaxially stipitate-glandular, margin with 8 to 19 teeth per side; inflorescences 1- to 5-flowered; bracts obtuse to rounded at apex ........ G. pyrolifolia

22. Shrubs 0.3–3.0 m tall; leaf blades 3.0– 12.7 cm long, abaxially gland-dotted to appressed setulose or setose, margin with 20 to 40(to 47) teeth per side; inflorescences 7- to 24-flowered; bracts acute to shortly acuminate at apex.

23. Branchlets sparsely hispid setose, setae generally appressed-ascending .................... ................................................. G. stapfiana

23. Branchlets densely hispid-setose, setae generally patent-erect ................. G. hookeri