Myriopteris myriophylla

Myriopteris myriophylla
Myriopteris myriophylla at UC Berkeley Botanical Gardens, 2015.
Conservation status
Secure  (NatureServe)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Division:	Polypodiophyta
Class:	Polypodiopsida
Order:	Polypodiales
Family:	Pteridaceae
Genus:	Myriopteris
Species:	M. myriophylla
Binomial name
Myriopteris myriophylla (Desv.) J.Sm.
Synonyms
Allosorus myriophyllus (Desv.) Farw. Cheilanthes elegans Desv. Cheilanthes fournieri C.Chr. Cheilanthes intermedia Baker Cheilanthes myriophylla Desv. Cheilanthes myriophylla var. elegans (Desv.) Baker Cheilanthes paleacea M.Martens & Galeotti Hemionitis myriophylla (Desv.) Christenh. Myriopteris elegans (Desv.) J.Sm. Myriopteris intermedia E.Fourn. nom. illeg. hom. Myriopteris paleacea (M.Martens & Galeotti) Fée

Myriopteris myriophylla, the Central American lace fern, is a species of lip fern. Despite its common name, this species is native as far south as Argentina. It is adapted to dry areas.

Taxonomy

In 1811, Nicaise Auguste Desvaux described two similar species, from Chile and South America respectively, which he named Cheilanthes elegans and Cheilanthes myriophylla.

The development of molecular phylogenetic methods showed that the traditional circumscription of Cheilanthes is polyphyletic. Convergent evolution in arid environments is thought to be responsible for widespread homoplasy in the morphological characters traditionally used to classify it and the segregate genera that have sometimes been recognized. On the basis of molecular evidence, Amanda Grusz and Michael D. Windham revived the genus Myriopteris in 2013 for a group of species formerly placed in Cheilanthes. One of these was C. myriophylla, which thus became M. myriophylla again. In 2018, Maarten J. M. Christenhusz transferred the species to Hemionitis as H. myriophylla as part of a program to consolidate the cheilanthoid ferns into that genus.

Further molecular studies in Myriopteris demonstrated the existence of three well-supported clades within the genus. M. myriophylla belongs to what Grusz et al. informally named the covillei clade. Members of the "core covillei" clade, including M. myriophylla, have leaves finely divided into bead-like segments. Within this clade, M. myriophylla is part of a subclade including M. chipinquensis, M. jamaicensis, M. rufa, M. tomentosa, and M. windhamii, most of which are apogamous.

Conservation

NatureServe considers it globally secure (G5), but vulnerable (S3) in Florida, at the northern end of its range.

Notes and references

Works cited

• Christenhusz, Maarten J. M.; Fay, Michael F.; Byng, James W. (2018). Plant Gateway's the Global Flora: A practical flora to vascular plant species of the world. Vol. 4. ISBN 978-0-9929993-9-1.
• Desvaux, A. N. [sic] (1811). "Observations sur quelques nouveaux genres de fougères et sur plusieures espéces nouvelles de la meme famille". Der Gesellschaft Naturforschender Freunde zu Berlin Magazine (in French). 5.
• Grusz, Amanda L.; Windham, Michael D. (2013). "Toward a monophyletic Cheilanthes: The resurrection and recircumscription of Myriopteris (Pteridaceae)". PhytoKeys (32): 49–64. doi:10.3897/phytokeys.32.6733. PMC 3881352. PMID 24399906.
• Grusz, Amanda L.; Windham, Michael D.; Yatskievych, George; Huiet, Lane; Gastony, Gerald J.; Pryer, Kathleen M. (2014). "Patterns of Diversification in the Xeric-adapted Fern Genus Myriopteris (Pteridaceae)". Systematic Botany. 39 (3): 698–714. doi:10.1600/036364414X681518. JSTOR 24546228.
• NatureServe (November 1, 2024). "Cheilanthes myriophylla". NatureServe Explorer. Arlington, Virginia. Retrieved November 17, 2024.