Didymoglossum hildebrandtii (Kuhn) Ebihara & Dubuisson

Ahamada H. Saïd, Sabine Hennequin, Germinal Rouhan & Jean-Yves Dubuisson, 2017, Disentangling the diversity and taxonomy of Hymenophyllaceae (Hymenophyllales, Polypodiidae) in the Comoros, European Journal of Taxonomy 313, pp. 1-53 : 14-15

Didymoglossum hildebrandtii (Kuhn) Ebihara & Dubuisson

Didymoglossum hildebrandtii (Kuhn) Ebihara & Dubuisson in Ebihara et al. , Blumea 51: 236 (2006). –

Trichomanes hildebrandtii Kuhn, Von der Decken’s Reisen in Ost­Afrika in 1859 bis 1861 3(3) Botanik: 70 (1879). – Type: ‘Johanna Isl.’, s. loc., s.d., J.M. Hildebrandt 1856 (holo-: K000435634!; iso-: P00139629!).

Short description

Epiphytic; long-creeping filiform rhizomes, rootless and densely covered by dense black trichomes, bearing widely separated fronds; fronds sessile and peltate, up to 6 cm long, mostly round and entire, with false veins parallel to true veins and palmate venation; sori numerous, pantotactic, cylindrical with a truncated mouth.

Global distribution

Comoros, Madagascar.

Distribution in Comoros

Anjouan, Mayotte, Mohéli.

Additional specimens examined

COMOROS: ANJOUAN, s. loc., 1905, Lavanchie s.n. (P00139628). MAYOTTE, Massif de Mtsapéré, Maison de la Convalescence, 10 Nov. 2002, F.Rakotondrainibe et al. 6669 (P00311382). MOHÉLI, Kidogobassi, 2 Nov. 2008, M.Pignal et al. 3456 (P02439793); Au-dessus de Drondroni, 26 Mar. 2011, C.Loup et al. 590 (P02439783); Au-dessus de Drondroni, 27 Mar. 2011, E.Bidault et al. 81 (P02439772).

Note

Didymoglossum hildebrandtii is clearly distinct with round and sessile peltate fronds which seem tightly appressed against the substrate ( Fig. 3C ). These features, unique for the family in the region, are shared with the Pacific and Asiatic D. tahitense (Nadeaud) Ebihara & K.Iwats. to which it is evolutionary closely related ( Ebihara et al. 2007).

Figures

Fig. 3. Representative Comorian Hymenophyllaceae as observed in situ in rainforests (here from Grande Comore or Mohéli). A. Endemic Didymoglossum kirkii (Hook.) Ebihara & Dubuisson (G. Rouhan et al. 925, P 00684886). B. Hymenophyllum sibthorpioides (Bory ex Willd.) Mett. ex Kuhn (G. Rouhan et al. 888, P 02439806). C. Didymoglossum hildebrandtii (Kuhn) Ebihara & Dubuisson (M. Pignal et al. 3456, P 02439793). D. Hymenophyllum kuhnii C. Chr. (G. Rouhan 897, P 02439807). E. Crepidomanes bipunctatum (Poir.) Copel. (G. Rouhan et al. 882, P 02439805). F. Hymenophyllum hirsutum (L.) Sw. (M. Pignal et al. 3487, P 02439796). Photographs by G. Rouhan. Scale bars = 1 cm.