Mickelia

Mickelia is a genus of ferns in the family Dryopteridaceae, subfamily Elaphoglossoideae, in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). It is one of the six genera of bolbitidoid ferns and is sister to the very large genus "Elaphoglossum". It consists of about 10 species. All are native to the neotropics.
Description.
Hemiepiphytic or terrestrial ferns. Rhizomes dorsiventral, the ventral meristele elongate in cross section. Phyllopodia absent. Leaves articulate at base or continuous with the rhizome, dimorphic as sporophylls and trophophylls, the sporophylls having longer petioles and smaller pinnae. Fronds never differentiated into bathyphylls and acrophylls as in the bolbitidoid genera "Lomagramma", "Arthrobotrya", and "Teratophyllum". Fronds singly pinnate or bipinnate with a single, free, basal segment on each of the basal pinnae. Pinnae articulate or continuous with the rachis; terminal pinna conform (similar in size and shape to the lateral pinnae). Veins variously anastomosing (not free); veinlets usually included in the areoles. Sori acrostichoid (covering the entire abaxial surface of the leaf); Paraphyses absent. Spores monolete.
Comparative anatomy.
No single character is known to distinguish "Mickelia" from "Bolbitis", but the rhizomes of five species of "Mickelia" have been examined and found to have ground tissue that is greenish, instead of the whitish color found in most ferns. The greenish rhizome ground tissue might be a synapomorphy for "Mickelia". Seven species of "Mickelia" are hemiepiphytes, whereas all of the "Bolbitis" species are terrestrial. The location of vegetative buds, when present, is different in the two genera.
Taxonomy.
The genus "Mickelia" was erected in 2010, following a molecular phylogenetic study of the bolbitidoid ferns, based on DNA sequences of the chloroplast intergenic spacers trnL-F and rps4-trnS. "Mickelia" was named for the American pteridologist John Thomas Mickel, who contributed much regarding "Elaphoglossum", the closest relative of "Mickelia".
Six species of "Mickelia" had previously been in the genus "Bolbitis". "Mickelia pradoi" and "Mickelia furcata" were first described in the paper that established "Mickelia". "Mickelia scandens" was resurrected from "Mickelia guianensis", which had previously been in "Lomagramma" because of its venation pattern. These two had been treated as a single species since the time when they were both in the genus "Acrostichum". For this reason, the most recent species name that had been applied to "Mickelia scandens" was "Acrostichum scandens".
The species that had been in "Bolbitis" were described in a monograph of that genus in 1977. The mesoamerican species of "Bolbitis" were given an updated treatment in 1995 and detailed biogeographic information for these was published in 2004. "Mickelia" was first described in a synopsis of the genus that did not repeat much of the information published in previous works.
Phylogeny.
The phylogenetic tree below is based on one that was published in 2010. The positions of "Mickelia pradoi" and "Mickelia lindigii" are based on morphology only. "Mickelia furcata" and "Mickelia pergamentacea" are omitted because they have not been sampled for DNA and morphology does not clearly indicate their affinities. "Mickelia furcata" is known from only one specimen collected in 1985 and lacking fertile fronds.
Species.
, the "Checklist of Ferns and Lycophytes of the World" accepted the following species and one hybrid: