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Abstract Parablechnumis the most diverse genus in the fern family Blechnaceae, with about 70 species, mainly from Central and South America, the Austropacific, and a few in Africa. Species delimitation inParablechnumis challenging, and regional studies vary in species recognized. This genus is generally found in humid mid- to high-elevation forests, especially in the Andes. Ecuador is notable for its high species richness, particularly in the poorly explored Cordillera del Cóndor, a sub-Andean range with a distinctive geology contributing to high plant diversity and endemism. Since the early 2000s, botanical expeditions have revealed numerous endemic species, highlighting the region's significance. In 2006, an unusualParablechnumspecies was collected in the Cordillera del Cóndor. Here, we describe it as a new species,Parablechnum shuariorum. It grows on sandstone cliffs along small rivers and can be distinguished by its fertile fronds, which are shorter than its sterile ones, and its densely scaly rachis. This species, endemic to the Cordillera del Cóndor, is found at elevations of 900–1,600 m. It is named after the Shuar people, whose lands include the collection sites. Preliminary conservation assessment suggests thatP. shuariorumis endangered due to a limited area of occupancy and threats from human activities, such as mining.
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This content will become publicly available on January 30, 2026
The Andes of Colombia and Ecuador as a Barrier to Fern and Lycophyte Species from Mesoamerica
We compiled a list of the fern and lycophyte species that occur in Mesoamerica and extend into Colombia and Ecuador, where they are restricted to the western side of the Andes; that is, they occur only west of the crest of the easternmost cordillera and are absent from that cordillera’s eastern slope and in adjacent Amazonia. We found 131 species with this Mesoamerican and west-of-the-eastern-cordillera distribution. Those 131 species constitute 7% of the total 1805 fern and lycophyte species that have been recorded west of the crest of the easternmost cordillera in Colombia and Ecuador. All 131 species have elevation ranges with midpoints at low (0–900 m) or middle (900–3000 m) elevations, and none occur above 3000 m. This suggests the cordilleras have acted as elevational barriers. We also investigated the blockage of these 131 species by each of the Andean cordilleras. We found that 75 (57%) of the 131 species were limited eastward by the western cordillera, 15 (11%) by the central cordillera (this cordillera in Colombia only), and 40 (31%) by the eastern cordillera. If estimates of endemics to the western Andean region are considered, then at least 20%–22% of all fern and lycophyte species in the region are restricted west of the crest of the easternmost cordillera. Although usually exhibiting larger geographic distributions compared to angiosperms, fern and lycophyte species may show significant geographic restriction by mountain ranges.
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- Award ID(s):
- 2330409
- PAR ID:
- 10616303
- Publisher / Repository:
- Missouri Botanic Garden Press
- Date Published:
- Journal Name:
- Annals of the Missouri Botanical Garden
- Volume:
- 110
- ISSN:
- 0026-6493
- Page Range / eLocation ID:
- 88 to 110
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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