Mendoncia, Vand., Fl. Lusit.

Magnaghi, Emily B. & Daniel, Thomas F., 2017, Systematics of Mendoncia (Acanthaceae: Thunbergioideae) in the Paleotropics, Proceedings of the California Academy of Sciences 64 (3), pp. 37-94 : 93-94

Key to Species of Mendoncia in Continental Africa

1a. Young stems, petioles, peduncles, and abaxial surface of bracteoles pubescent with at least some branched (stellate to dendritic) trichomes..................................... 2

1b. Young stems, petioles, peduncles, and abaxial surface of bracteoles glabrous or pubescent with unbranched trichomes only..................................................... 3

2a. Inflorescences borne in leaf axils on young, mostly herbaceous, leafy stems; corollas 17. 5–22 mm long; style 16–18 mm long; drupes mealy-glandular (lacking elongate trichomes); leaves 44–133 mm long and 23–86 mm wide................................ M. combretoides

2b. Inflorescences mostly borne at naked nodes on older, woody, leafless stems; corollas 29.3–31. 8 mm long; style 22. 8–27 mm long; drupes pubescent with eglandular trichomes to 0.6 mm long; leaves 86–200 mm long and 57–114 mm wide........................ M. phytocrenoides

3a. Inflorescences mostly borne on peg-like, woody, sometimes branched short-shoots at naked nodes on older, woody, leafless stems; young stems, peduncles, and abaxial surface of leaves glabrous to mealy-glandular, lacking elongate trichomes; drupe oblong (symmetrical), 12.3–19. 9 mm long................................................. M. lindaviana

3b. Inflorescences borne in leaf axils on young, mostly herbaceous, leafy stems; young stems, peduncles, and abaxial surface of leaves pubescent (sometimes sparsely so) with eglandular trichomes to 2.3 mm long; drupe ± irregularly shaped, overall obovoid and widest at or just below apex, 6.8–11. 8 mm long......................................... M. gilgiana

Key to Taxa of Mendoncia in Madagascar and Mayotte

1a. Ovary and drupe glabrous or mealy-glandular (i.e., with inconspicuous, sessile glands mostly <0.05 mm in diameter), lacking elongate, eglandular trichomes; bracteoles abaxially glabrous to sparsely pubescent (rarely densely pubescent); calyx glabrous or sparsely pubescent..... 2

1b. Ovary and drupe pubescent with elongate, eglandular trichomes; bracteoles abaxially densely pubescent; calyx usually densely pubescent........................................ 4

2a. Corollas pink or light to dark purple, 20–35 mm long, upper lip 10–17 mm long; bracteoles usually lacking dense pubescence at apex of adaxial surface; extension of connective beyond anther thecae pubescent with glandular and eglandular trichomes 0.1– 0.3 mm long; drupe subspherical to spherical, 14. 8–25 mm in diameter; northern Madagascar....... M. vinciflora

2b. Corollas white and usually with purple markings near base of limb and/or throat (rarely purplish in M. delphina ), 8–18. 5 mm long, upper lip 2–12. 5 mm long; bracteoles with dense pubescence at apex of adaxial surface; extension of connective beyond anther thecae (if present) glabrous to minutely glandular; drupe ovoid-ellipsoid to ellipsoid to spherical to obovoid, 6–15. 7 mm in diameter; widespread.............................................. 3

3a. Dichasia 1–2 in axils of leaves; apex of leaf blade acuminate to caudate, with tail-like apex to 12 mm long; bracteoles yellowish, lacking a pair of conspicuous, whitish, bulbous, gall-like basal protuberances; stigma subequally to unequally 2-lobed; pollen 5-aperturate; southern Madagascar........................................................ M. delphina

3b. Dichasia 1–4 (–8) in axils of leaves or commonly in axils of bracts in an a raceme to 15 cm long; apex of leaf blade (acuminate) to acute to rounded to truncate to retuse, and sometimes with an apiculum to 1.6 mm long; bracteoles green, often with a pair of conspicuous, whitish, bulbous, gall-like basal protuberances; stigma capitate; pollen mostly 4-aperturate; widespread................................................................. M. flagellaris

4a. Corollas 13. 2–19 mm long, tube 10–14 mm long; leaf blades mostly with length:width 1.4–1.8...................................................................... M. kely

4b. Corollas 26–49 mm long, tube 20–38; leaf blades mostly with length:width 1.7–2.8....... 5

5a. Corollas white with purplish markings, limb 20.6–32. 4 mm in diameter, upper lip 13.5 mm long with lobes 8–10 mm long and 11.2–13. 2 mm wide, lower lip 16. 5–19 mm long with lobes 9.4–13. 5 mm long and 12.2–15. 2 mm wide................................ M. decaryi

5b. Corollas light pink to dark pink (sometimes whitish externally), limb 6–21 mm in diameter, upper lip 1. 8–10 mm long with lobes 1.8– 7.4 mm long and 3.7–8. 6 mm wide, lower lip 3–12. 4 mm long with lobes 2.2–7. 5 mm long and 3.4–9. 1 mm wide.......................... 6

6a. Young stems, petioles, abaxial surfaces of leaf blades and bracteoles, and peduncles subglabrous and/or pubescent with erect to flexuose to antrorse trichomes, underlying surfaces plainly visible; corolla with upper lip 4. 4–10 mm long and lobes of lower lip 3.5–7. 5 mm long and 3.5–9. 1 mm wide................................ Mendoncia cowanii var. cowanii

6b. Young stems, petioles, abaxial surfaces of leaf blades and bracteoles, and peduncles densely pubescent with flexuose-interwoven trichomes such that underlying surfaces not visible (or only partially so on abaxial surface of leaf blades); corolla with upper lip 1.8– 3.6 mm long and lobes of lower lip 2.2–3. 3 mm long and 3.4– 3.5 mm wide......... Mendoncia cowanii var. coursii