Euonymus Tour. ex L.

Shrubs or small trees. Leaves opposite, decussate, alternate, rarely spiral; stipules caducous. Flowers in axillary cymes, rarely in fascicles, bisexual, 5 or 4-merous. Sepals deeply lobed, imbricate, entire-denticulate. Petals spreading or reflexed, entire, crenulate, toothed or fimbriate, imbricate. Stamens inserted on the disc; filaments short; anthers deltoid, dehiscent on the top, lateral or introrse. Ovary immersed in the disc. Ovules 2 in each locule. Fruits capsular, lobed, angular or winged, smooth or spiny, when dehiscing the valves splitting and leaving no central axis. Seeds arillate.

Mainly in tropical and subtropical Asia and C. & N. America, fewer species in Europe and Africa; ca 176 species, 32 in India.

Literature. BLAKELOCK, R.A. (1951). A synopsis of the genus Euonymus. Kew Bull. 210-290.

KEY TO THE SPECIES

1a. Winter buds ovoid. small; filaments distinct; anthers 2-celled. dehiscing with two distinct slits; capsules of various shapes. if oblate-globose then not winged

2

b. Winter buds conic. large; filaments obscure; anthers 1-celled, dehiscing by one continuous slit; capsules oblate-globose. winged

26

2a. Flowers fascicled or sometimes in fasciculately arranged 1-3-tlowered short and obscure peduncles; tall trees

20. Euonymus javanicus

b. Flowers in axillary, usually many flowered, sometimes dichotomous cymes, on conspicuous peduncles (peduncles sometimes short or lacking in E. indicus); small trees or shrubs

3

3a. Capsules partite almost to base

4

b. Capsules not partite or partite up to middle only

5

4a. Flowers 5-merous: inflorescence 6-15-flowered; petals fringed, oblong. white

25. Euonymus pendulus

b. Flowers 4-merous; inflorescence 1-7-flowered; petals entire, rounded, green

22. Euonymus lawsonii

5a. Capsules smooth

6

b. Capsules echinate

25

6a. Capsules lobed, angled or winged. apex retuse, acute or obtuse; small trees or erect shrubs

7

b. Capsule unlobed or with shallow rounded lobes, apex rounded or nearly so; climbing shrubs

23

7a. Flowers 2-2.5 cm across; disc 6-8 mm wide; capsule rounded

16. Euonymus grandiflorus

b. Flowers up to 12 mm in diam. (up to 18 mm in E. tingens); disc 2-5 mm wide; capsules turbinate, obconie or clavate. rarely rounded

8

8a. Leaves up to 3 cm long; petiole up to 3 mm long

29. Euonymus tibeticus

b. Leaves 5.5-24 cm long; petiole 0.3-3 cm long

9

9a. Leaves deciduous; petals oblong-lanceolate, with revolute margins

18. Euonymus hamiltonianus

b. Leaves persistent petals orbicular

10

10a. Petals fringed or denticulate; leaves entire

11

b. Petals entire or crenulate; leaves serrate or entire

13

11a. Leaves elliptic or obovate-oblong, petals yellowish to greenish; yellow

8. Euonymus cochinchinensis

b. Leaves lanceolate; petals purple

12

12a. Cymes 7 or more-flowered; petiole 1-2 cm long

4. Euonymus attenuatus

b. Cymes 1-3 -flowered; petiole 3-8 mm long

19. Euonymus indicus

13a. Flowers 4-merous

14

b. Flowers 5-merous

16

14a. Leaves bullate. up to 20 cm long

5. Euonymus bullatus

b. Leaves not bullate, less than 13 cm long

15

15a. Capsule 8-10 mm long, rounded at base, lobes rounded; leaves serrate to base

32. Euonymus viburnoides

b. Capsule 15-20, mm long, pyriform. lobes angled; leaves serrate in uppr half

21. Euonymus kachinensis

16a. Capsule 4 mm long

23. Euonymus macrocarpus

b. Capsule up to 2.5 mm long

17

17a. Petals with conspicuous black veins; flowers 10-18 mm in diam.

30. Euonymus tingens

b. Petals without black veins; flowers under 12 mm across

18

18a. Inflorescence of 1-3-flowered solitary peduncles

10. Euonymus crenulatus

b. Inflorescence 7-or more-flowered dichotomous cymes

19

19a. Twigs acutely 4-angled, almost winged

2. Euonymus angulatus

b. Twigs terete

20

20a. Leaves 6 cm or below in length. entire; petals entire

11. Euonymus dichotomus

b. Leaves more than 7 cm long, serrate or crenate; petals crenulate, rarely entire

21

21a. Leaves sharply serrate to base

27. Euonymus serratifolius

b. Leaves crenate-serrate only towards apex

22

22a. Petals white or greenish

15. Euonymus glaber

b. Petals purplish

24. Euonymus paniculatus

23a. Leaves sessile or sub-sessile petiole not more than 2.5 mm long

17. Euonymus griffithii

b. Leaves distinctly petioled petiole 0.5 - 1.25 cm long

24

24a. Veins conspicuously reticulate above in leaves; capsules greenish

28. Euonymus theifolius

b. Veins obscure in leaves; capsules brownish

31. Euonymus vagans

25a. Capsules greenish when dry; prickles more than 2 mm long

6. Euonymus cinereus

b. Capsules brownish when dry; prickles less than 2 mm long

12. Euonymus echinatus

26a. Flowers 5-merous

27

b. Flowers 4-merous

28

27a. Leaves deciduous, oblong, elliptic or ovate, entire; petals cream coloured

3. Euonymus assamicus

b. Leaves persistent lanceolate, serrulate; petals pruple

7. Euonymus clivicolus

28a. Leaves deciduous

29

b. Leaves persistent or nearly so

30

29a. Leaves ovate, biserrate or fringed (uniserrate in E. flmbriatus var. serratus); peduncles 5-8 cm long; petals white or greenish; capsule wings 6-15 mm long

13. Euonymus fimbriatus

b. Leaves lanceolate, not fringed or biserrate; peduncles 3-4 cm long; petals purple; capsule wings 2-7 mm long

1. Euonymus amygdalifolius

30a. Capsule wings up to 12 mm long, attached more toward the middle of the capsule; veins arising at an acute angle to the midrib

9. Euonymus cornutoides

b. Capsule wings up to S mm long, attached towards the base of the capsule; veins arising at an angle of 45° or more to the midrib

31

31a. Leaves up to 30 cm long; apex acuminate; inflorescence 7-15-flowered

14. Euonymus frigidus

b. Leaves up to 8 cm long; apex obtuse; inflorescecne 3-7-flowered

26. Euonymus pygmeus

List of Lower Taxa