Inversodicraea ledermannii (Engl.) Engl.

Tchouto, P. & Burgt, X. van der, 2017, A synoptic revision of Inversodicraea (Podostemaceae), Blumea 62 (2), pp. 125-156 : 137

9. Inversodicraea ledermannii (Engl.) Engl.

Inversodicraea ledermannii (Engl.) Engl. (1915) 274;(1926) 463; (1930) 58; Taylor (1954) 127. — Dicraea ledermannii Engl. (1909) 381. — Ledermanniella ledermannii (Engl.) C. Cusset (1974) 274; (1983) 377; (1987) 72. — Type: Ledermann 225 (holo B destroyed; isotype BM, U n.v.), Cameroon, S. Region,‘Wasserfall, Gross-Batanga station, 10–12 m, auf Felsen unter wasser oberhalb der Fälle im ‘Lobe’. Podostem. Kleines Pflänzchen in Wasser. Blüht weiss-grün, konnt in ganzen kolonien vor.’fl., 10 Aug.1908.

Etymology. Named for Karl Ledermann the collector of the type specimen, and of specimens that became the types of many other new species of Podostemaceae and other families which were published by Engler.

Distribution — Angola, Cameroon, Gabon, Guinea,IvoryCoast, Sierra Leone.

Habitat & Ecology — The upper banks of rapids, first to be exposed as the water levels drop at the end of the wet season, in full sun; 0–400 m altitude.

Conservation — Inversodicraea ledermannii (as Ledermanniella ) was listed on www.iucnredlist.org as Least Concern in 2009 ( Diop 2010c). However, the species is not in fact recorded from some of the countries in which it is claimed to occur in that publication, such as Ghana, Senegal, Niger, Togo, etc. Despite this it is probably, with I. tenax , the most common and widespread species of the genus and therefore we do not contest this assessment.

Additional specimens. ANGOLA, Bengo, River at Bela Vista, Exp. Zool. Staat. 1959 ( HBG n.v.) . – CAMEROON, SW Region, Korup National Park , N5°01' E8°50', 50 m alt., 5–15 Dec. 1984, D. Thomas 4135A (K, P00179325 image) . – DRC, N. Lukafu, valley of Lofoi R., Schmitz 1833 ( BR n.v.) . – GABON, Rapides de l’Ogooué au passage de la route de Mimongo à Koula Moutou , fr., 25 June 1926, Le Testu 5983 (P00179326 image) . – GUINEA, Guinée- Forestière, Beyla Prefecture, Mts Bèro , fl., 22 Nov. 2008, P.M. Haba 242 (BR, G, HNG, K, MO, P, SERG, WAG) . – IVORY COAST, Mt Cavally, Pays de Dyolas, au pied de Mt Dô , 750 m alt., prés Gouékangouine , st., 2 May 1909, Chevalier 21421 (P00179316 image) .– SIERRA LEONE, small waterfall in Rokel River; Kabala to Makeni , Northern province , 22 Mar. 1971, P.W. Richards 7320 (K, P00179375 image) .

Notes — This, with I. tenax , is the most widespread and frequent species of the genus. There is a large geographic disjunction between the populations in Guinea-Ivory Coast and those in Cameroon-Angola, and it is possible that these correspond with two different taxa. It is not yet clear how much morphological support there is for this idea. The matter was first discussed by Taylor (1953). Those specimens above not seen by us were studied and cited by Cusset (1983).

The isotype of I. bosii at K appears to be I. ledermannii . Hybridisation and possibly introgression, is suspected to have occurred between I. ledermannii and I. bosii in Cameroon, and with I. harrisii in Sierra Leone (this paper).

Inversodicraea ledermannii is distinctive for the three, more or less triangular, equal, lobes, each of which is about half the length of the entire leaflet and has an acute apex.

Caution should be used before identifying material as this species in West Africa, since material originally identified thus later proved to be separate species, e.g., I. pygmaea and I. harrisii .