Senecio ser. Culcitium (Bonpland) Cuatrecasas, 1950

Salomón, Luciana, Sklenář, Petr & Freire, Susana E., 2018, Synopsis of Senecio series Culcitium (Asteraceae: Senecioneae, Senecioninae) in the Andean region of South America, Phytotaxa 340 (1), pp. 1-47 : 6-7

Key to Species of Senecio ser. Culcitium

1. Style branches penicillate..................................................................................................................................................................2.

– Style branches penicillate with a tuft of long hairs.........................................................................................................................23.

2. Rosulate herbs; stem reduced or absent; capitula solitary (rarely 2–4), sessile................................................................................3.

– Scapiform or subscapiform herbs (flowering stems densely leafy at the base and with a few leaves along them); capitula solitary or in corymbiform cymes..................................................................................................................................................................4.

3. Leaves entire, margin crenate............................................................................................................................................ S. expansus

– Leaves partite (deeply cleft, more than half the distance to the midvein)....................................................................... S. hyoseridis

4. Capitula solitary.................................................................................................................................................................................5.

– Capìtula 2–25...................................................................................................................................................................................13.

5. Plants densely tomentose...................................................................................................................................................................6.

– Plants glabrous or subglabrous........................................................................................................................................................10.

6. Leaves strongly discolorous ................................................................................................................................................. S. pflanzii

– Leaves conspicuously concolorous...................................................................................................................................................7.

7. Plants over 40 cm tall, woolly ......................................................................................................................................... S. canescens

– Plants up to 30 cm tall, adpressed-woolly.........................................................................................................................................8.

8. Leaf blade linear-lanceolate or oblong-spathulate, margin entire.....................................................................................................9.

– Leaf blade oblanceolate-spathulate, margin irregulary dentate or sinuate, rarely entire................................................... S. candollei

9. Plants 15–30 cm tall, woolly ................................................................................................................................................. S. nivalis

– Plants 10–15 cm tall, barbate-lanate.............................................................................................................................. S. ferrugineus

10. Plants 6–9 cm tall; calycular bracts 10–12, 1-seriate ...................................................................................................... S. cajonensis

– Plants 10–30 cm tall; calycular bracts 26–36, 2–4-seriate..............................................................................................................11.

11. Basal leaves oblanceolate or oblanceolate-spathulate, margin serrate-dentate ............................................................ S. serratifolius

– Basal leaves linear or linear-oblong, or linear-lanceolate, margin entire (rarely slightly mucronate)............................................12.

12. Leaf blade linear or linear-oblong, 2–7 cm long ............................................................................................................ S. hypsobates

– Leaf blade linear or linear-lanceolate, 20–22 cm long ......................................................................................................... S. timidus

13. Leaf blade abaxial surface glabrous or subglabrous........................................................................................................................14.

– Leaf blade abaxial surface densely pilose; plants densely pilose at least on abaxial surface of leaves..........................................18.

14. Plants 12–20 cm tall; basal leaves with leaf blade elliptic or suborbicular...................................................................... S. violifolius

– Plants 30–50 cm tall; basal leaves with leaf blade oblanceolate-spathulare or oblong...................................................................15.

15. Phyllaries 12–14; basal leaves oblanceolate-spathulate............................................................................................. S. tephrosioides

– Phyllaries 14–21; basal leaves oblong.............................................................................................................................................16.

16. Basal leaves petiolate ................................................................................................................................................ S. praeruptorum

– Basal leaves sessile or attenuate into a pseudopetiole.....................................................................................................................17.

17. Stems leafy; phyllaries 14–21 ........................................................................................................................................... S. burkartii

– Stems scapiform; phyllaries ca. 21............................................................................................................................... S. punasessilis

18. Plants glandular pilose.................................................................................................................................................... S. rhizomatus

– Plants lanose....................................................................................................................................................................................19.

19. Plants over 40 cm tall......................................................................................................................................................................20.

– Plants up to 30 cm tall.....................................................................................................................................................................22.

20. Leaves conspicuously concolorous; involucre 30–50 × (40–) 50–80 mm ...................................................................... S. canescens

– Leaves discolorous; involucre 12–16 × 20–30 mm .........................................................................................................................21.

21. Capitula 4–25; phyllaries 18–24.................................................................................................................................... S. culcitioides

– Capitula 2–3; phyllaries 28–30......................................................................................................................................... S. supremus

22. Capitula 13–14; leaf blade linear-oblong, apex obtuse ............................................................................................. S. leucophorbius

– Capitula 2–9; leaf blade oblanceolate or oblanceolate-spathulate, apex acute or obtuse...................................................... S. keshua

23. Herbs rosulate, scapiform, whitish woolly; capitula solitary (rarely 2–3) ...................................................................... S. cocuyanus

– Herbs or subshrubs, whitish woolly to glabrous; stems subscapiform to leafy; leaves alternate; capitula solitary or arranged in corymbs...........................................................................................................................................................................................24.

24. Erect shrubs-subshrubs or herbs......................................................................................................................................................25.

– Scandent subshrubs.........................................................................................................................................................................35.

25. Leaf margin entire...........................................................................................................................................................................26.

– Leaf margin serrate-dentate or erose...............................................................................................................................................33.

26. Leaves whitish woolly on both surfaces or adaxial surface lanuginose (occasionally subglabrous) and abaxial surface whitish woolly; leaf margins slightly revolute or flat ................................................................................................................... S. lingulatus

– Leaf blade adaxial glabrous or subglabrous and leaf blade adaxial whitish woolly; leaf margin conspicuously revolute .................

27. Stems subscapiform (flowering stems densely leafy at the base and with a few leaves along them).............................................28.

– Stems uniformly leafy.....................................................................................................................................................................31.

28. Capitula solitary or 2–8; phyllaries and calycular bracts densely tomentose..................................................................................29.

– Capitula 2–11; phyllaries and calycular bracts subglabrous...........................................................................................................30.

29. Leaf blade narrowly ovate, attenuate at the upper part ................................................................................................ S. gargantanus

– Leaf blade elliptic-oblong............................................................................................................................................... S. puracensis

30. Leaf blade linear or linear-ovate............................................................................................................................................... S. josei

– Leaf blade ovate or ovate-lanceolate ............................................................................................................................... S. otophorus

31. Leaves sessile, leaf blade linear or linear-oblong, 0.1–0.3 (–0.4) cm wide ............................................................... S. imbaburensis

– Leaves petiolate, leaf blade rounded to ovate or linear oblong, 0.2–1.1 cm wide..........................................................................32.

32. Leaf blade linear-oblong, 2–4 cm long................................................................................................................. S. superparamensis

– Leaf blade rounded 0.4– 2 cm long............................................................................................................................. S. superandinus

33. Leaves auriculate.............................................................................................................................................................. S. antisanae

– Leaves not auriculate.......................................................................................................................................................................34.

34. Herbs or subshrubs; leaves densely woolly on both surfaces or at least on abaxial surface, petiole 0.7– 2 cm long, cylindrical ........ .............................................................................................................................................................................. S. longepenicillatus

– Robust herbs; leaves glabrous or subglabrous, petiole 7–19 cm long, flattened.......................................................... S. mojandensis

35. Leaf blade ovate, ovate-lanceolate, or deltoid.................................................................................................................................36.

– Leaf blade linear-oblong, oblong-lanceolate or elliptic...................................................................................................................39.

36. Leaf blade ovate, ovate-lanceolate, leaf margins conspicuously revolute ...................................................................... S. otophorus

– Leaf blade ovate-lanceolate, or deltoid, leaf margins flat...............................................................................................................37.

37. Stem glabrous to subglabrous.................................................................................................................................... S. campanulatus

– Stem tomentose...............................................................................................................................................................................38.

38. Petioles usually flat-wiged; leaf blade deltoid; phyllaries 12–14................................................................................ S. pindilicensis

– Petioles cylindric; leaf blade ovate; phyllaries 18–20................................................................................................ S. betonicifolius

39. Calycular bracts deltoid or ovate, 2–4-seriate .............................................................................................................. S. involucratus

– Calycular bracts linear-lanceolate, 1-seriate....................................................................................................................................40.

40. Petiole flat-winged.................................................................................................................................................... S. alatopetiolatus

– Petiole cylindrical............................................................................................................................................................................41.

41. Basal leaves auriculate....................................................................................................................................................................42.

– Basal leaves not auriculate..............................................................................................................................................................44.

42. Phyllaries 21; corolla 6–7 mm long............................................................................................................................... S. piedrahitae

– Phyllaries 9–14, corolla 8–12 mm long............................................................................................................................................43

43. Leaf blade oblong-lanceolate ................................................................................................................................................ S. patens

– Leaf blade oblong or ovate-oblong......................................................................................................................... S. subinvolucratus

44. Leaf blade elliptic, cuneate at base, glabrous, leaf margin conspicuously revolute........................................................ S. cuencanus

– Leaf blade linear-oblong, rounded at base, densely woolly or arachnoid-tomentose abaxially, leaf margin revolute or flat.............. ....................................................................................................................................................................................... S. doryphyllus