Mendoncia cowanii (S. Moore) Benoist, Bull. Mus. Hist. Nat.

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 : 56-58

2a. Mendoncia cowanii (S. Moore) Benoist, Bull. Mus. Hist. Nat. (Paris). 31:387. 1925.

Afromendoncia cowanii S. Moore, J. Bot. 44:150. 1906. Monachochlamys cowanii (S. Moore) S. Moore, J. Bot. 67:226, in clavi. 1929.

TYPE.— MADAGASCAR. Fianarantsoa: Tanala, [ca. 21°51ʹ30ʺS, 47°26ʹ30ʺE], 1880, Deans Cowan s.n. (lectotype, designated here: BM-000930924- photo!). var. cowanii

Afromendoncia madagascariensis S. Moore, J. Bot. 44:150. 1906. Mendoncia madagascariensis (S. Moore) Benoist, Bull. Mus. Hist. Nat. (Paris) 31:387. 1925, non Radlk. (1884). Monachochlamys madagascariensis (S. Moore) S. Moore, J. Bot. 67:227, in clavi. 1929.

TYPE.— Province unknown: Central Madagascar, Baron 3810 (lectotype, designated here: BM-000930923-photo!; isolectotypes: K-000393676 photo!, P-00493668!).

Young stems subglabrous to pubescent with an understory of mostly erect, unbranched, eglandular trichomes ˂ 0.05– 0.2 mm long, and an overstory of yellowish, antrorse to flexuous, unbranched, eglandular trichomes 0.3– 2 mm long, sometimes either overstory or understory trichomes soon breaking off or deciduous. Leaves membranaceous to coriaceous, petioles to 17 mm long, pubescent like young stems, blades ovate to elliptic (to obovate), 25–120 (–140) mm long, (11–) 16–63 (–77) mm wide, (acute to) rounded (to subcordate) at base, acute to acute-apiculate to acuminate at apex, abaxial surface pubescent with cauline type trichomes (sometimes denser on major veins), except with trichomes sometimes erect and overstory trichomes up to 3 mm long, domatia consisting of dense tufts of interwoven trichomes often conspicuous in axils of primary and secondary veins on abaxial surface as well, adaxial surface sparsely pubescent with erect to antrorse, unbranched, eglandular trichomes to 1 mm long, trichomes often denser on or mostly restricted to midvein and often with conspicuous pustullate bases. Inflorescences borne in leaf axils on young, mostly herbaceous and leafy stems, solitary or opposite at nodes, dichasia 1–3 per axil, peduncles to 47 mm long, pubescent like young stems. Bracteoles green (sometimes tinged with maroon) to dark purplish, mostly deciduous as fruit matures, ovate to elliptic to obovate, (11–) 16–31 mm long, 7–20 mm wide, rounded at base, rounded to rounded- to acute-apiculate at apex, apicule to 1 mm long, abaxial surface mealy-glandular and pubescent with erect to flexuose, unbranched, eglandular trichomes 0.2– 2 mm long, adaxial surface mealy-glandular. Calyx glabrous to densely pubescent with erect to antrorsely appressed, unbranched, eglandular trichomes 0.05–2 mm long. Corolla light pink to dark pink (sometimes whitish externally), externally glabrous, internally glabrous, 26–45 mm long, tube 20–38 mm long, limb 6–21 mm diameter, upper lip 4. 4–10 mm long with lobes emarginate, reflexed, 2–7. 4 mm long and 3.7–8. 6 mm wide, lower lip 5.7–12. 4 mm long with lobes emarginate, reflexed, 3.5–7. 5 mm long and 3.5–9. 1 mm wide. Stamens 7–10 mm long, ventral pair inserted ca. 1 mm distal to dorsal pair, thecae 3.6– 6.1 mm long, densely pubescent at base with a tuft of bristles 0.1– 0.3 mm long, connective extending 0.2– 0.4 mm beyond thecae, extension of connective attenuate, glabrous, staminode not seen. Pollen 5–6-colpate, E = 37–41 µm, P = 36–38 µm, P:E = 0.974–0.980, C = 10–10.8 µm, C: P = 0.263–0.297, rugulae microverrucate to microgemmate. Style 20–32. 5 mm long, glabrous throughout or sometimes proximally pubescent with eglandular trichomes, stigma subequally 2-lobed with lobes 0.1– 0.5 mm long. Drupe ovoid to ellipsoid to oblong, 11–21 mm long, 6. 6–17 mm diameter, surface mealy-glandular and pubescent with yellowish, erect to flexuose to antrorse, unbranched, eglandular trichomes to 0. 1–3 mm long.

PHENOLOGY.— Flowering: February–September with peak flowering February–March; fruiting: August–December.

DISTRIBUTION AND HABITATS.— Eastern Madagascar (Antananarivo, Antsiranana, Fianarantsoa, Toamasina, Toliara; EOO = 298,998 km 2; Fig. 9 ). Plants occur in lowland to montane to cloud, primary and secondary, moist to wet, evergreen forests. Elev. 50–1200 m.

ILLUSTRATIONS.— Benoist (1967:5, Fig. 1 ); Figs. 10 , 11A–D .

In the protologue of Afromendoncia cowanii, Moore (1906) cited an unnumbered collection of Deans Cowan at BM and Baron 289 at K. The lectotype designated above is the more complete specimen (e.g., containing flowers, which are described in the protologue). The lectotype of Afromendoncia madagascariensis is chosen from the two collections of Baron from “central Madagascar ” cited in the protologue. Baron 3810 was noted by Moore (1906) to contain flowers and fruits, whereas Baron 1448 was noted to be a fruiting collection. The protologue has descriptions of both flowers and fruits. The lectotype at BM is particularly complete, and better reflects information in the protologue than the isolectotype at K, which contains the major set of Baron’s collections from Madagascar. In describing these two species Moore (1906:151) perceptively noted that they were unlike their African congeners, but that they “bear a treacherous resemblance to each other, being as regards foliage virtually indistinguishable.”

Leaves of Mendoncia cowanii var. cowanii vary from membranaceous (e.g., Malcomber 2119, Randriamboavonjy et al. 838) to conspicuously coriaceous (e.g., Daniel et al. 10400, Razafindrabe et al. 157). Irrespective of texture, leaves of this taxon frequently possess acarodomatia in axils of major veins on their abaxial surfaces. Seigler 12818 is unusual in having fruiting pedicels up to 4 mm long and calyces to 7.7 mm long with one or more deep lobes (to 5.8 mm long).

Because flowers are most useful to adequately distinguish between M. cowanii and M. decaryi , specimens lacking them often cannot be identified with certainty (see under M. decaryi below for additional distinctions).

REPRESENTATIVE SPECIMENS EXAMINED.— MADAGASCAR. Antananarivo: Beanana (Fenoarivo), [ca. 18°23ʹS, 46°22ʹE], Bosser 930 ( P) ; Mandraka , P.K. 69, route d’Antananarivo à Toamasina, ca. 18°55ʹS, 47°56ʹE, Dorr & Rakotozafy 2776 ( MO) ; ca. 164 km W de Tsiroanomandidy, région de Bongolava , [18°52ʹ19.77ʺS, 45°33ʹ25.61ʺE], Randriamboavonjy et al. 838 ( CAS) . Antsiranana: Réserve Naturelle Intégrale de Tsaratanana, Beangona, Fok. Ambinany Beangona , Fir. Marotolana , Fiv. Ambanja , 14°01ʹS, 048°47ʹE, Antilahimena et al. 536 ( BR, CAS, MO) ; Naturelle Marojejy, along trail to summit of Marojejy Est, NW of Mandena, 14°27ʹS, 049°47ʹE, Miller 3372 ( MO) ; Réserve Naturelle de Marojejy; western slopes of Mt. Beondroka , 14°27ʹS, 49°47ʹE, Miller & Randrianasolo 4374 ( MO) ; Réserve Naturelle de Marojejy; along the trail to the summit of Marojejy Est, N of Mandena , 14°26ʹS, 049°46ʹE, Miller & Randrianasolo 4576 ( MO) ; environs d’Antalaha , [ca. 14°54ʹS, 50°16ʹ30ʺE], Perrier de la Bathie 2169 (K, P) ; Montagne d’Ambre , partie sud, 12°41ʹ03ʺS, 049°10ʹ28ʺE, Randimbiarison & Ramandimbimanana 188 ( CAS) ; Marojejy RN 1, Sambava, ca. 10 km à vol d’oiseau de Maroambihy à 310° au NW, ca. 6 km à vol d’oiseau de Mandena à 318° NW, soit 13 km suivant la piste entre Mandena et le sommet de Marojejy , 14°26ʹ30ʺS, 049°46ʹ20ʺE, Rasoavimbahoaka 589 ( MO) ; Marojejy RN 1, Andapa, ca. 3.5 km a vol d’oiseau de Marovato (80° NE) , et 2 km a vol d’oiseau de Sarahandrano (60° NE) , soit 8 km environ a pied, 14°36ʹ10ʺS, 49°39ʹ50ʺE, Rasoavimbahoaka 647 ( MO) . Fianarantsoa: Ranomafana Natl. Park, Talatakely Trail System, downslope from the BT trail toward the Namorona River surrounding a small natural pond, 21°15ʹS, 047°15ʹE, Almeda et al. 8055 ( CAS) ; Midongy du Sud, Beharena , 23°31ʹ05ʺS, 047°05ʹ34ʺE, Andrianjafy 1234 ( MO) ; Ranomafana Natl. Park, Talatakely trail system S of Namorona River, 21°16ʹS, 047°25ʹE, Daniel et al. 9037 ( CAS) , Daniel et al. 9116 ( CAS) , 9255 ( CAS), 11002 ( CAS); 7 km W of Ranomafana, just S of Namorona river, Duke Primate Center study site, 21°16ʹS, 047°25ʹE, Daniels 98 ( CAS, MO) ; Parc Natl. Ranomafana, Parcelle #3, Talatakely , piste vers Vohiparara , 21°15ʹS, 047°27ʹE, Kotozafy 139 ( MO); PN 45 Parc Natl. Ranomafana , between Fianarantsoa and Ifanadiona , around cabine de reserche S of Namorona River , Malcomber 998 ( MO) ; Ranomafana Natl. Park, Parcelle I, near village of Miaranony, Anosimasina, 21°09ʹS, 047°32ʹE, Malcomber 1589 ( MO) ; Fivondronana Ivohibe, Firaisana Ivohibe, limite N de la Réserve Speciale d’Ivohibe le long de la rivière Ifefitany , 7.5 km ENE d’Ivohibe, campement 1, 22°28ʹ12ʺS, 046°57ʹ36ʺE, Rakotovao et al. 837 ( MO) ; Haute Matsiatra, Ranomafana Natl. Park, Bevoahazo , 21°11ʹ43ʺS, 047°28ʹ55ʺE, Ranarivelo et al. 971 ( CAS) ; Ranomafana Natl. Park , piste touristique de Vohiparara E du village de Vohiparara, direction NE piste B, Ifanadiana, 21°14ʹS, 047°23ʹE, Ravololonanahary 3 ( MO) ; Ivohibe, Ivongo, Ambarongy, RN 1 Andringitra , 22°13ʹS, 47°01ʹE, Razafindrabe 157 ( MO) ; Réserve Speciale #7, Manombo , 37 km S of Farafangana, parcel W of RN12, 23°02ʹS, 047°42ʹE, Schatz 3188 ( MO) ; near Ranomafana, near village of Ambodiamotana, Seigler 12818 (K, MO, P) . Toamasina: Andasibe-Mantadia Natl. Park, Parc a Orchidées , 18°56ʹ00.5ʺS, 048°24ʹ51.9ʺE, Almeda et al. 9245 ( CAS) ; route Moramanga à Anosibe , [ca. 18°54ʹ6.29ʺS, 048°03ʹ16.30ʺE], Bosser & Millot 6470 ( P) ; Analamazaotra, [ca. 18°56ʹS, 48°26ʹE], Capuron 565-S.F. (K, P) ; Forêt d’Analamazoatra, Capuron s.n. ( P) ; Andasibe, Analamazoatra ( Perinet ), Cheek & Dransfield B1383 ( CAS) ; piste d’Ambatoharanana, massif du Rahobevava Bemainty, [ca. 18°00ʹS, 048°40ʹE], Cours 4152 ( P) ; de Didy à Brickaville, Cours 4847 ( P) ; 7 km N de Perinet vers Tamatave, Cremers 1482 ( MO, P) ; forest reserve in vicinity of Perinet, along Route #2 between Tananarive and Tamatave, Croat 32280 ( MO) ; Special Reserve Perinet-Analamozoatra in Andasibe ( Perinet ); Daniel & Butterwick 6721 ( CAS) ; Parc Natl. de Mantadia, ca. 10 km N of Andasibe, trail to piscine along Andranomanaponga River ( Rinasoa Trail ), 18°49ʹ30ʺS, 048°25ʹ48ʺE, Daniel et al. 10400 ( BR, CAS) ; Andasibe-Mantadia Natl. Park, Mantadia section, 14–19 km NE of RR station in Andasibe , 18°50ʹS, 048°26ʹE, Daniel & Ranarivelo 10539 ( CAS, TAN) , Daniel et al. 11000 ( CAS, TAN) ; S de Moramanga, Decary 7005 ( P) ; forêt S de Moramanga , [ca. 18°59ʹ14.42ʺS, 048°15ʹ12.73ʺE], Decary 7043 ( P) ; Forêt de Sandrangato S de Moramanga, [ca. 19°06ʹ30ʺS, 048°14ʹ30ʺE], Decary 17755 (K, P) , 17785 (K, P); environs de Andasibe-Perinet , 18°56ʹS, 048°25ʹE, Dorr & Barnett 3207 ( MO) ; Analamazaotra, Jardin Botanique Tana ( TAN) 2160 ( P); Forêt d’Analamazaotra, Keraudren-Aymonin & Aymonin 25362 ( P) ; Betampona Réserve Naturelle Integrale , 40 km NW of Toamasina, [ca. 17°54ʹ46ʺS, 049°13ʹ06.62ʺE], Lewis & Razafimandimbison 667 ( MO) ; Andasibe-Perinet, N of road from Antananarivo to Tamatave , 1 km along trail SW of old C. T.F. T. sawmill at Analamazoatra, Lowry & Schatz 4264 ( CAS, MO) ; NE of Moramanga, at nickel mining exploration site, Ambatovy, plot 6 of Golder map, 18°51ʹ34ʺS, 048°18ʹ25ʺE, McPherson 17517 ( MO) ; Analamazaotra, Perrier de la Bathie 10265 ( P) ; Forêt d’Andasibe, sur l’Onive, Perrier de la Bathie 17048 ( P) ; Betampona, Ambodiziena, W de Tamatave , Perrier de la Bathie 17408 ( P) ; Moramanga Distr., Andasibe, Forêt d’Analamazaotra ( Perinet ), Pettersson & Nilsson 253 (K) ; canton de Ambodiriana, district de Tamatave, Rakotoniaina 5343-RN (K, P) ; canton: Imerimandroso, district: Ambatondrazaka, Rakotonao 10894RN ( P) , 10895RN ( P); forestry station of Analamazaotra, SE of the old road between Moramanga and Andasibe, 18°56ʹS, 048°26ʹE, Randrianansolo 427 ( MO) . Toliara: along road through mountain in Chaines Anosyennes from Fort Dauphin ( Taolagnaro ) to Ranomafana , Croat 31844 ( MO) ; haute vallée de la Manampanihy [ca. 24°33ʹ30ʺS, 047°04ʹ30ʺE], entre le col de Saindro et Eminiminy , Humbert 14023 ( P) ; NW of Taolagnaro, Réserve Naturelle Integrale #11 (Andohahela), parcelle I, NW of Eminiminy, beside River Itrotroky , 24°38ʹS, 46°46ʹE, Malcomber 2119 ( MO) ; Fort Dauphin (Taolagnaro), NW of town along road to Ranomafana , 24°46ʹS, 46°53ʹE, McPherson & Rabevohitra 14970 ( CAS, MO) ; Integrale Réserve #11, Andohahela, Parcelle 1, SW of Eminiminy, Manatavona River, 24°40ʹS, 46°48ʹE, Randramampoinona 599 ( BR, MO) . Province not determined: Madag. Centre, Baron 289 ( P) ; central Madagascar, Baron 1448 (K, P) ; Madagascar, Baron 2586 (K, P) ; central Madagascar, Baron 3810 ( P) ; north Madagascar, Baron 6143 (K) ; without locality, Homolle s.n. ( P) ; Cameaka, Jardin Botanique Tana ( TAN) 3689 ( P); without locality, Perrier de la Bathie 15968 ( P) .

Figures

FIGURE 9. Maps of Madagascar showing distributions of Mendoncia cowanii var. cowanii, M. cowanii var. coursii, and M. vinciflora.

FIGURE 1. Phylogenetic relationships among genera of Acanthaceae sub- family Thunbergioideae and Avicennia. OW = Old World, NW = New World. Adapted from Borg et al. (2008).

FIGURE 10. Mendoncia cowanii var. cowanii (A, B, G, Daniel et al. 9116; C–F, Daniel et al. 11000). A. Fertile node with a single dichasium in fruit. B. Portion of midvein and secondary veins, showing domatia, on abaxial surface of leaf. C. Flower partially encased by subtending bracteoles. D. Corolla tube split open to show androecium. E. Flower following dehiscence of corolla. F. Calyx, nectar disc, and pubescent ovary with style emerging. G. Seed. Drawn by Sarah Adler and Anya Illes.

FIGURE 11. Mendoncia cowanii (A–D) and M. flagellaris (E, F). A. Mature drupe. B. Corolla limb showing discoloration due to insect visitation. C, D. Flowers with corolla tube encased by fluid-filled bracteoles. E. Immature drupes. F. Flower and bracteoles, each with a pair of prominent, white, and basal protuberances. (A–D, photos by T. Daniel of Daniel et al. 11000; E, photo [cropped] of Razanatsima et al. 422, copyright by Aina Razanatsima on Tropicos [www.tropicos.org/Image/100126998], CC by-NC-ND 3.0; F, photo by T. Daniel of Daniel et al. 9239).