Hymenophyllum polyanthos (Sw.) Sw., J. Bot. (Schrader) 1800

Kessler, Michael & Smith, Alan R., 2017, Prodromus of a fern flora for Bolivia. X. Hymenophyllaceae, Phytotaxa 328 (3), pp. 201-226 : 210

Hymenophyllum polyanthos (Sw.) Sw., J. Bot. (Schrader) 1800 (2). 1801.

= Trichomanes polyanthos Sw., Prodr. 137. 1788.

Range: —Antilles; central Mexico to Bolivia (BE, CH, CO, LP, SC), Argentina ( Arana et al. 2016, Larsen & Ponce 2016), Paraguay, and southern Brazil; Africa; eastern Asia.

Ecology: —Very common; epiphytic and on fallen trunks, often high in the canopy, but also lower down; (500–) 900–2000(–3500) m.

Notes: — Hymenophyllum polyanthos is the commonest Hymenophyllum in lowland and foothill forests, and the name is applied here in a broad sense, as used in floras throughout the tropics and subtropics of the world. It is a variable species in a taxonomically difficult species complex that is greatly in need of monographic study. Hymenophyllum protrusum Hook. [= H. polyanthos var. protrusum (Hook.) Farw. ], known from the Antilles and Venezuela, may occur in Bolivia. It differs from H. polyanthos by having exserted receptacles (i.e., resembling H. apiculatum and H. trichomanoides but with obtuse involucral bases). Petioles are winged, at least distally.

According to limited sampling by Hennequin et al. (2006), Hymenophyllum polyanthos s.l. is polyphyletic, suggesting that true H. polyanthos (type from Jamaica) may be restricted to the Neotropics. However, much more sampling and further study is needed throughout the tropics to arrive at a modern monophyletic definition of this and the many closely related and named taxa comprising the complex, even those in the New World.