Baccharis subgen. Tarchonanthoides

Heiden, Gustavo & Pirani, José Rubens, 2016, Taxonomy of Baccharis subgen. Tarchonanthoides (Asteraceae: Astereae: Baccharidinae), a group from the southeastern South American grasslands and savannas, Phytotaxa 241 (1), pp. 448-450 : 448-450

Key to the species of Baccharis subgen. Tarchonanthoides

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4. Phanerophytes; pappus of female florets not accrescent......................................................... A. B. sect. Tarchonanthoides 2 Chamaephytes; pappus of female florets accrescent .............................................................................B. sect. Canescentes 7 Capitulescences corymbose ............................................................................................................. I. B. ser. Curitybenses 3 Capitulescences racemose or paniculate ............................................................................................................................... 5 Pappus bristles of male florets with twisted apex, not broadened apically; cypselae glabrous or puberulous, sparsely covered by twin trichomes ......................................................................................................................... 1. B. chionolaenoides Pappus bristles of male florets with straight or flexuous apex, broadened apically; cypselae pubescent, densely covered by twin trichomes ...................................................................................................................................................................... 4 Shoots virgate; leaves evenly distributed along branches; peduncles with a pilose indumentum; pappus bristles of male florets not twisted; female floret with style 3–3.4 mm long, pappus 3.6–4 mm long......................................2. B. curitybensis

TAXONOMY OF BACCHARIS SUBGEN. TARCHONANTHOIDES

Phytotaxa 241 (1) © 2016 Magnolia Press • 5

- Shoots ascending; leaves crowded at distal part of branches; peduncles with a tomentose indumentum; pappus bristles of male florets flexuous; female floret with style 3.9–4.2 mm long, pappus 2.9–3.2 mm long ........................... 3. B. nebularis

5. Shoots patent; leaves sessile; capitulescence racemose; pappus bristles of male florets tortuous apically; female corolla with a subapical wreath of trichomes; cypselae glabrous, pappus multiseriate ............... II. B. ser. Colliculatae 4. B. patens

- Shoots virgate; leaves petiolate, capitulescence paniculate; pappus bristles of male florets not twisted apically; female corolla without a subapical wreath of trichomes; cypselae pilose or glabrescent, pappus uniseriate ..................................... .................................................................................................................................................. III. B. ser. Tarchonanthoides 6

6. Shoots, abaxial surface of leaves and peduncles tomentose; male corolla 1.6–2.2 mm long, pappus 1.5–2.1 mm long, bristles straight; cypselae 1.7–2 mm long, glabrescent, sparse biseriate glandular trichomes near apex.........5. B. lychnophora

- Shoots, abaxial surface of leaves and peduncles villose; male corolla 2.8–3.4 mm long, pappus 2.7–3 mm long, bristles basally tortuous; cypselae 1.4–1.6 mm long, puberulous, evenly covered by twin trichomes .......... 6. B. tarchonanthoides

7. Male florets with glabrous lobes ................................................................................................. IV. B. ser. Gnaphalioides 8

- Male florets with trichomes on the lobes .......................................................................................... V. B. ser. Canescentes 9

8. Shoots tomentose; abaxial surface of leaves lanose; male corolla 3.2–3.5 mm long, pappus bristles tortuous; female florets with style 5.5–6.1 mm long; cypselae 1.2–1.9 mm long.......................................................................... 7. B. gnaphalioides

- Shoots villose; abaxial surface of leaves tomentose; male corolla corolla 2.2–2.7 mm long, pappus bristles flexuous; female florets with style 2.9–3.3 mm long; cypselae 0.9–1.1 mm long ...................................................... 8. B. leucopappa

9. Capitulescences racemose .................................................................................................................................................. 10

- Capitulescences corymbose or paniculate ........................................................................................................................... 11

10. Fertile shoots ascending; leaves cordate, ovate to oblong, 1-nerved (hyphodromous), sericeous abaxially; male capitula 4.7–6 mm long; female capitula 6.2–6.7 mm long; cypselae 1.2–1.4 mm long ................................................ 9. B. gibertii

- Fertile shoots pendulous; leaves lanceolate, 3-nerved, imperfect acrodromous, tomentose abaxially; male capitula 6.5–8 mm long; female capitula 8–20 mm long; cypselae 2–2.4 mm long ....................................................... 10. B. leucocephala

11. Leaves with felted indumentum abaxially; male and female clinanthia globose, puberulous or glabrescent .... 11. B. uleana

- Leaves with tomentose indumentum abaxially; male and female clinanthia conical, slightly convex or flat, pubescent ... 12

12. Shoots tomentose; capitulescence corymbose; male corolla 2.2–2.8 mm long; female corolla 2.2–2.7 mm long; cypselae 0.8–1.1 mm long ..........................................................................................................................................12. B. phylicifolia

- Shoots villose; capitulescence paniculate; male corolla 3.6–4.2 mm long; female corolla 3.6–4 mm long; cypselae 1.2–1.4 mm long ................................................................................................................................................. 13. B. helichrysoides