Inversodicraea mortonii (C.Cusset) Cheek

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

1. Inversodicraea mortonii (C.Cusset) Cheek

Inversodicraea mortonii (C.Cusset) Cheek in Cheek & Haba (2016a) 2. — Ledermaniella mortonii C. Cusset (1983) 368, f. 1. — Type: Morton in SL 2899 (holotype WAG n.v.; isotype K), Sierra Leone, Gbenge Hills,opposite Bumban School, fl., fr., 28 Nov. 1965.

Etymology. Named for the collector of the type specimen, Prof. Morton , botanist, specialist in West African Labiatae , Compositae , and Commelinaceae who was based in Sierra Leone and Ghana in the 1960s and 1970s, concluding his career at the University of Waterloo in Canada.

Distribution — Sierra Leone.

Habitat & Ecology — ‘Stem creeping over wet smooth rocks of drying-out stream’; 5–225 m altitude.

Conservation — Inversodicraea mortonii is not listed on www.iucnredlist.org. Two locations only are known for this species. Despite targeted searches for Podostemaceae in Sierra Leone 2009–2016 for the Bumbuna and Yiben hydroelectric projects, and for the Tonkolili iron project, I. mortonii has not yet been rediscovered. Inversodicraea mortonii has not been seen for over 35 years. However, neither of the two known localities for this species are known to have been searched at the correct season. Since we know of no immediate direct threats at either of the two localities, the species is here assessed as Near Threatened. Given that the area of occupancy can be estimated as 2 km 2 using the preferred IUCN cell size of 1 km 2, I. mortonii should be reassessed as Endangered, EN B2 ab(iii) should any threat materialise, such as a hydroelectric or mining project.

Additional specimen. SIERRA LEONE, Rapids , 4.2 km downstream of Mano , Taia River (River Jong, River Pampam), N8°01' W12°07', fr., 28 Feb. 1981, P.J.C.Harris 12 (P00179338 image) .

Note — Remarkable for the uniformly subulate (awl-like), linear-conical scale-leaves with rounded apices. Unlikely to be confused with any other species.