Inversodicraea gabonensis (C.Cusset) Cheek

Tchouto, P. & Burgt, X. van der, 2017, A synoptic revision of Inversodicraea (Podostemaceae), Blumea 62 (2), pp. 125-156 : 134

2. Inversodicraea gabonensis (C.Cusset) Cheek

Inversodicraea gabonensis (C.Cusset) Cheek in Cheek & Haba (2016a) 2. — Ledermanniella gabonensis C. Cusset (1983) 368,f. 2. — Type: Le Testu 6017 (holotype P00179287 image), Gabon, Haut Ngounyé (now Ngounié Province), ‘rapides de l’Ogoulou à Mitingo’, fl., fr., 19 July 1926.

Etymology. Named for Gabon, the home of the type specimen.

Distribution — Congo-Brazzaville, Gabon.

Habitat & Ecology — In the spray of waterfalls in small rivers or streams in the evergreen forest zone; 200–600 m altitude.

Conservation — Inversodicraea gabonensis is not listed on www.iucnredlist.org.The only known location is upstream of the nearly completed hydroelectric dam at the Imperatrice Falls on the Ngounié so is expected not to be affected. Two other locations occur in the Republic of Congo. The first at Foulakari is a local tourist destination near Brazzaville. The second remote in the upper headwaters of the Nyanga in Massif du Chaillu near the Gabonese border. No threats have been detected by us at these locations. However, we have made no direct observations. Given an area of occupation of 3 km 2, this species would be assessed as Endangered, EN B2 ab(iii) if any threat were known. Since we know of no threats at these localities, the species is here assessed as Near Threatened. Given that the number of hydroelectric projects in Africa is increasing rapidly, such threats might materialise at any time.

Additional specimens. GABON (type), Congo-Brazzaville (Republic of Congo), Chutes de Foulakari , fl., fr., 13 Aug. 1969, Attims 202 (P00179288 image); ibid., fr., 13 Oct. 1968, F. Hallé 1467 (IEC, P00179289 image); ibid., fr., 6 Sept. 1972, Sita 3448 (IEC, P00179291 image); Chutes de la Nyanga à Mouvoungou, fl., 18 May 1925, Le Testu 5459 (P00179290 image) .

Note — Similar to I. tholloni , I. kamerunensis , I. boumiensis (also C. Africa), I. pepehabai and I. liberia (W. Africa) in having scale-leaves membranous, irregularly or not lobed, loosely held or spreading (not appressed) on slender, sparsely branched, short (2–5 cm long) more or less erect stems. Distinct for the lanceolate scale-leaves often with a side lobe, apices rounded, flowers 1-anthered, pollen in monads.