Alansmia M.Kessler, Moguel, Sundue & Labiak, Brittonia

Smith, Alan R., Kessler, Michael, León, Blanca, Almeida, Thaís Elias, Jiménez-Pérez, Iván & Lehnert, Marcus, 2018, Prodromus of a fern flora for Bolivia. XL. Polypodiaceae, Phytotaxa 354 (1), pp. 448-450 : 448-450

Alansmia M.Kessler, Moguel, Sundue & Labiak, Brittonia 63(2): 238. 2011.

The species of this genus were originally placed in one of five subgroups of Terpsichore by Smith (1993; Group 3, the T. lanigera group). Recent molecular studies ( Ranker et al. 2004, Labiak et al. 2010b) have shown that this subgroup is not closely related to the others, and is best treated as a distinct genus. As a consequence, this group was given a new name, Alansmia , by Kessler et al. (2011), and the genus subsequently monographed by Moguel Velázquez & Kessler (2013). Alansmia is monophyletic and supported by several morphological synapomorphies: setae present on the rhizomes; cells of the rhizome scales turgid; both surfaces of the rhizome scales ciliate; blades membranaceous; and sporangial capsules setose ( Kessler et al. 2011). Other diagnostic characters include pendent fronds with seemingly indeterminate growth; concolorous, orange to castaneous rhizome scales; petioles usually <1 cm long; hydathodes sometimes cretaceous; and setae simple, paired, or clustered (appearing stellate). The group also exhibits the uncommon characteristic of producing both trilete and monolete spores, sometimes on the same plant; often, monolete spores are binucleate when shed ( Smith 1993). With the exception of the paired or clustered hairs, these characters are also found in some species of Terpsichore , Lellingeria , Mycopteris , and other grammitid genera, but not in combination. Additionally, certain characters have been evolutionarily lost in certain taxa, e.g., A. elastica lacks rhizome scales entirely.

Alansmia comprises 26 species, all but two in the Neotropics, the others in Africa and Madagascar ( Moguel Velázquez & Kessler 2013, Bauret et al. 2017). Nine species are known from Bolivia. Species of Alansmia typically grow in sheltered microhabitats, often pendent on the lower side of large tree branches or beneath leaning trees. There, they cannot be directly reached by rain and presumably obtain most of their moisture from fog. This growth habit appears to be closely linked to the hairy covering seen in many species, as also shown by species of Hymenophyllum subg. Sphaerocionium ( Smith & Kessler 2017) that share the microhabitat with Alansmia . The physiological role of the hairs remains to be explored.