Stemodia scoparioides, Hassl. ex Minod, 1918

Sosa, Maria De Las Mercedes & Dematteis, Massimiliano, 2013, Taxonomic position and identity of Stemodia scoparioides (Gratiolae, Plantaginaceae), Phytotaxa 135 (1), pp. 35-42 : 36-37

Key to distinguish Stemodia scoparioides and sympatric species

1. Leaves bi-pinnatipartite; corolla irregularly campanulate ....................................... S. hassleriana Chodat (1904: 287)

- Leaves entire; corolla bilabiate, upper lip emarginate, lower lip with three lobes ....................................................... 2

2. Small herbs up to 25 cm, decumbent; flowers solitary, axillary ................................................................................... 3

- Plants erect, over 20 cm; flowers arranged in clusters or spiciform inflorescences ..................................................... 4

3. Leaves ovate, petiolate (petiole 4–8 mm); calyx ebracteolate.................................................................. S. verticillata

- Leaves linear, sessile; calyx with two bracteoles ........................................................................................................... .......................................................................................... S. ericifolia ( Kuntze 1898: 239) K. Schumann (1900: 395)

4. Stems and leaves with pedicellate trichomes ............................................................................................................... 5

- Stems and leaves exclusively with punctate trichomes ................................................................................................ 9

5. Corolla 12–16 mm; floral bracts mostly long as 2 times as long as the subtended flowers; leaves linear, linear-lanceolate, lanceolate or oblanceolate, apex attenuate .......................................................................................................... 6

- Corolla 5–10 mm; floral bracts shorter than the subtended flowers; leaves obovate to oblong-lanceolate, attenuate at base, apex acute.............................................................................................................................................................7

6. Leaf blades linear to linear-lanceolate, 10–40 × 0.5–3 mm, basally attenuate....................................... S. scoparioides

- Leaf blades lanceolate to oblanceolate, 40–80 × 5–18 mm, basally auriculate, clasping the stem .......... S. lanceolata

7. Herbs up to 50 cm; leaves obovate to ovate-elliptic, base clasping and somewhat flanged ........................... S. stricta

- Herbs up to 150 cm; leaves lanceolate to oblong-lanceolate, base slightly auriculate ................................................ 8

8. Herbs 30–80 cm, inflorescence branched; leaves 20–80 × 5–20 mm, margin slightly serrate (less than 20 teeth on each side)......................................................................................................................................................................... ... S. durantifolia var. chilensis ( Bentham 1831: tab. 1470) C. C. Cowan in B. L. Turner & C. C. Cowan (1994: 290)

- Herbs 60–150 cm, inflorescence simple; leaves 60–100 × 15–45 mm; margin tightly serrate (more than 20 teeth on each side).......................................................................................... S. hyptoides Chamisso & Schlechtendal (1828: 8)

9. Leaf margin entire or barely denticulate, not amplexicaul ............................. S. palustris A. Saint-Hilaire (1824: 216)

- Leaf margin sharply serrated, basally amplexicaul ................................................ S. lobelioides Lehmann (1837: 91)