A personal highlight for me during field work in Papua New Guinea this year was finding Tomophyllum beleense (Fig. A). These plants have thin membranaceous laminae covered in long hairs. They are confined to relatively dry, protected areas, usually beneath limbs or trunks of large trees. They show remarkable similarity to the Neotropical genus Alansmia (Fig. B), which has similar morphology and is found in the same habitat niche. The suite of characters associated with this habit has evolved multiple times among grammitid ferns, but is perhaps best developed in these two lineages. I have taken to calling it the Terpsichorean syndrome, taking a cue from Earl Bishop. Bishop chose the name Terpsichore, after the Greek muse of dance, for the American species that displayed these characters because of the way the slender petioles and rachises allow them to move in the wind. As you can guess now, the genus (later described by Alan Smith in 1993) was polyphyletic; the Terpsichorean syndrome evolves multiple times in grammitid ferns. The total number of independent evolutionary events, and the ecophysiological significance of these characters remain important questions to our ongoing research efforts.
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