Mecodium

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 : 24

Subgenus Mecodium

Subgenus Mecodium potentially groups five species in the area including eastern and southern Africa and the western Indian Ocean. These species are morphologically close and are thus often confused ( Fig. 5 ): paleotropical populations of supposedly H. polyanthos (Sw.) Sw. , East and South-African and Indian Ocean H. capense Schrad. , East and South-African H. kuhnii C.Chr. , the western Indian Ocean H. fumarioides Bory ex Willd. and H. inaequale (Poir.) Desv. In the fern flora of South Africa, Sim (1915) considered H. capense as a synonym of H. fumarioides , and H. inaequale is cited in the area but not H. kuhnii contrary to the other more recent local floras (e.g., Burrows 1990). Roux (2009) restricted H. fumarioides (the type is a mixed collect from Mauritius and La Réunion: J.B.G.M. Bory de St.­ Vincent 119, holotype BW20229010, isotype P00547028) and H. inaequale to the Indian Ocean and Tanzania, H. capense being treated as a distinct species with a wider distribution including the Indian Ocean, eastern Africa and South-Africa.

Our investigations allowed us to recognize and propose here only three species for subg. Mecodium in the archipelago as we will discuss here-after. These species are H. capense , H. inaequale and H. kuhnii .

Figures

Fig. 5. Western Indian Ocean Hymenophyllum subg. Mecodium, illustrating morphological resemblance of taxa which are difficult to distinguish (see text). A. Hymenophyllum kuhnii C. Chr. from Comoros, firstly identified as H. polyanthos (Sw.) Sw. (F. Rakotondrainibe et al. 6864, P 00312328). B. Hymenophyllum capense Schrad. from Madagascar, initially identified as H. fumarioides Bory ex Willd. (F. Rakotondrainibe et al. 6121, P 00212664). C. Syntype of Hymenophyllum kuhnii C. Chr. from Tanzania (B 200092782). D. Hymenophyllum inaequale (Poir.) Desv., representative specimen from La Réunion (L. Bauret 190, P).