Mendoncia iodioides (S.Moore) Heine

Breteler, F. J. & Wieringa, J. J., 2018, A synopsis of Mendoncia (Acanthaceae) in continental Africa including the description of two new species from western Central Africa and a new subspecies from West Africa, Blumea 63 (2), pp. 109-119 : 115

5. Mendoncia iodioides (S.Moore) Heine — Map 5

Mendoncia iodioides (S.Moore) Heine (1962) 180. — A fromendoncia iodioides S. Moore (1913) 74. — Monachochlamys iodioides (S.Moore) S. Moore (1929) 226. — Mendoncia phytocrenoides (Gilg ex Lindau) Benoist var. iodioides (S.Moore) Heine (1966) 74 (as ‘ ioides’), partly,see note. — Type: P.A. & D.A. Talbot 388 (holo BM; iso K), Nigeria, Oban, 1911.

Distribution — SE Nigeria, SW Cameroon.

Additional specimens studied. CAMEROON, South-West Region, Van Andel et al. 3729 ( WAG), Cameroon Mt, Njonje, 20 June 2001 .

Conservation status — The areas of occupancy (AOO) is 8 km 2 while the extent of occurrence (EOO) cannot be calculated for only two collections. The species is evaluated as Critically Endangered because the recent collection originates from the very margin of a protected area in an area with high population pressure, while the collection by Talbot is over a century old, from an unprotected site, and it has not been found in Nigeria since, so we infer past and future decline of habitat and population size (CR, B2a,b(i, ii, iii, iv, v)).

Note — Heine (1966) reduced M. iodioides to a variety of M. phytocrenoides , but consequently, in Flore du Gabon as well as on his identification slips in the Paris herbarium, used ioides instead of iodioides . This is not permissible when referring to Moore’s specific epithet, and it is in this paper treated as an orthographic error. The character by which Heine distinguished his two varieties in the Flore du Gabon ( Heine 1966) is found in the type of indumentum, mainly composed of stellate hairs for the type variety and mainly of simple hairs for var. iodioides . This difference in indumentum indeed exists, but should be attributed the other way around, M. phytocrenoides has an indumentum of mainly simple hairs. The illustration on p. 75 of the Flore du Gabon shows the type variety with mainly simple hairs and not var. iodioides . Moreover, Mann 1839, the type of M. phytocrenoides , is not the only collection of the type variety as Heine (1966) claimed. Here again he confounded the two varieties because at that time it was var. iodioides that was known only by the type. Magnaghi & Daniel (2017) consider iodioides as a synonym of phytocrenoides because they found the pubescence character to be not consistent, but also because they state that the varieties overlap geographically. But besides the difference in indumentum, there are more characters to differentiate between these two species, notably the size and shape of the bracteoles and the length of the pedicel, and in our delimitation their distributions do not overlap. Therefore, Mendoncia iodioides is here reinstated as a distinct species. Moore (1913) described the style of Afromendoncia iodioides as hairy. Investigation of the holotype from BM revealed a glabrous style like in Van Andel 3729 (WAG), the second collection of this species. At present fruits of M. iodioides are unknown.

Figures

Map 5 Distribution of Mendoncia iodioides (S.Moore) Heine.