This is a black-stemmed twice-pinnate Asplenium with a proliferous flagelliform leaf tip. Plants like this have generally been treated as A. flabellulatum Kunze in neotropical floras, but that name does not appear to be correctly applied here. The leaf cutting of this plant is a better match for A. lindenii Hook., a name which has been placed in synonymy and forgotten.  It is illustrated in Index Filicum. Alan Smith (UC) directed me to the type of A. lindenii, Schlim 608 from Ocana, Colombia, an image of which he had available as a C. V. Morton negative (no. 595, 6-7000). The BR specimens have been digitized are available at: http://plants.jstor.orgspecimen/br0000006965600 and http://plants.jstor.org/specimen/br0000006965907

This species group is need of taxonomic revision. However, for the time being  A. lindenii appears to be the most applicable name.