Inversodicraea pepehabai Cheek

Tchouto, P. & Burgt, X. van der, 2017, A synoptic revision of Inversodicraea (Podostemaceae), Blumea 62 (2), pp. 125-156 : 143

23. Inversodicraea pepehabai Cheek

Inversodicraea pepehabai Cheek in Cheek & Haba (2016a) 3. — Type: Pepe M. Haba 292 (holotype HNG; isotypes K, P), Guinea-Conakry , Guineé-Forestère , Seredu, Mt Ziama, N8°21'25.8" W9°18'30.7",fl., fr., 8 Feb.2010.

Etymology. Named for the collector of the only known specimen, Pepe Haba of N’zerekore, one of the most expert field botanists in Guinea, cofounder of the environmental NGO Guinée-Biodiversité.

Distribution — Republic of Guinea (Guinea-Conakry).

Habitat & Ecology — Rapids in submontane evergreen forest; c. 600 m a.s.l. altitude.

Conservation — Inversodicraea pepehabai was assessed in Cheek & Haba (2016a) as Endangered under Criterion D, since less than 250 individuals are estimated to have been observed at the single location known (EN D1). The AOO is assessed as 1 km 2. Currently there are no obvious threats to this species. But there is a risk that former activities within the Ziama Foret Classe are resumed. These activities are tea and quinine plantations, and timber extraction. Where any of these to happen then increased surface run-off can be expected. This would raise levels of nutrients and silt in the watercourse in which I. pepehabai is found. In turn this would increase algal growth that would compete with, and (due to increased silt levels), reduce establishment of new plants of the species. It is to be hoped that additional records of this species will be found at further sites, lowering its conservation assessment.

Additional specimens. GUINEA-CONAKRY, Guineé-Forestère , Seredu, Mt Ziama, N8°21'25.8" W9°18'30.7", fl., fr., 8 Feb. 2010, Pepe Haba 292 (holotype HNG; isotypes K, P) .

Notes — Inversodicraea pepehabai is unusual among African Podostemaceae being found in the rapids of a submontane forest area. Other species with this ecology are Saxicolella amicorum J.B.Hall ( Hall 1971; pers. obs. Cheek 1995), Ledermanniella letouzeyi C.Cusset ( Cusset 1987, Cheek et al. 2004), L. onanae Cheek ( Cheek 2003, Cheek et al. 2004), and L. pollardiana Cheek & Ameka ( Cheek & Ameka 2008) . Most other species of the genus occur in rapids of lowland forest or woodland habits.

The affinities of I. pepehabai are probably with other West African species of the genus which have slender, usually lobed, scale-leaves. At first sight I. pepehabai appears very similar to the relatively common and widespread I. ledermannii , but the scale-leaves in that species are consistently, deeply and equally 3-lobed, and cover most of the stem, being ± appressed, not patent. The scale-leaves of I. pygmaea ( L. taylori ) are also similar, but are also consistently 3-lobed resembling I. ledermannii excepting that the central lobe is always longer than the laterals, and again, the stems are short (1–2 cm long) and completely covered in scale-leaves. In I. mortonii the scale-leaves are needle-like, and completely lacking lobes. Most similar to I. adamesii , in the irregularly lobed (lobes 1, 2, or absent) scale-leaves which cover <50 % of the stem. Distinct in the scale-leaves being patent (not ± appressed), the flowers with 1 stamen (not 2), the fruits 8-ribbed (not 6).

Inversodicraea pepehabai is one of several plant species unique to the Ziama Massif inside the Ziama Man & Biosphere reserve. It is likely to be proposed in the future as an ‘Important Plant Area’ for Guinea (see Darbyshire, continuously updated). Several other new species have recently been discovered at this location in Ziama including Gymnosiphon samoritourei Cheek ( Cheek & Van der Burgt 2010) and Allophylus samoritourei Cheek ( Cheek & Haba 2016b) .