Inversodicraea cristata Engl.

5. Inversodicraea cristata Engl. View in CoL

Inversodicraea cristata Engl. (1915) View in CoL 276, f. 180A–M; (1926) 462; (1930) 58. — Ledermanniella cristata (Engl.) C. Cusset (1974) View in CoL 273; (1983) 372; (1987) 74. — Type: Ledermann 1173 (B holotype destroyed, lectotype selected here BM; isotype U n.v.), Cameroon, ‘Makaka’ ( Makaka Station ), ‘gr. Steine & Felsen in reissendem Bach im gebirgigen Walde’. ‘Podostem. mit grünlichen Bl. und rosaroten Blütenstielen’,fl., fr., 21 Nov. 1908, 500 m.

Etymology. Cristata meaning ‘crest’ may refer to the crest-like arrangement of tine-like divisions along the apex of the scale-leaves.

Distribution — Cameroon.

Habitat & Ecology — Rapids; 520–780 m altitude.

Conservation — Inversodicraea cristata is listed (as Ledermanniella ) on www.iucnredlist.org as VU B2 ab(iii) in 2007 by Ghogue (2010d). That assessment follows the protologue of Cusset (1983) which recognises the species as extending to Angola, C.A.R., Equatorial Guinea, and Gabon, as well as Cameroon. Yet, in studying these specimens for this paper, it was discovered that the only authentic records of this plant appear to be from Cameroon alone (see above). However, at the time of writing, not all of the specimens attributed by Cusset to I. cristata have been viewed and identified and therefore a formal reassessment of its conservation assessment cannot yet be made. However, the species is very likely threatened.

Additional specimens. CAMEROON, Maan ( 24 km ESE Nyabesan), rochers du lit du R. Mvigili, dans la NW du village, fl., fr., 6 Mar. 1963, J.& A. Raynal 10263 (P00179279 image; P00179280 image, YA) ; Mali, R. Fall, c. 8 km N. Bétaré Oya. fl., 5 Feb. 1966, Leeuwenberg 7761 (P00179278 image, WAG n.v., YA) .

Notes — Ledermanniella cristata is the type of Ledermanniella subg. Phyllosoma C. Cusset (1983) . Cusset’s delimitation of this subgenus is followed here, albeit elevated to generic level, as Inversodicraea , for which the type selected is I. tenax . The protologue of I. cristata Engl. (1915) cites no specimen but the figure is a good match for the BM sheet of Ledermann 1173, the number generally understood to be its basis (e.g., cited in Engler (1926) and cited as type by Cusset (1974) and so is selected as lectotype here. Cusset’s (1983) concept of I. cristata was broad, including discordant elements. For example, Gossweiler 9291 ( Angola) is in fact I. digitata (see under that species), while Tisserant 3210 (C.A.R., ‘Riv. Koyali, Bozoum’, 7 Jan. 1933, P00179281 image; P00179282 image) has an uncertain placement, needing further research. Neither of these specimens matches the illustration in the protologue, nor the type specimen itself, which has 9–12 long, slender, tine-like scale-leaf lobes. Therefore the material assigned to this species requires reassessment since more than one species is probably involved.