The Blakeeae (Melastomataceae) are a tribe traditionally comprised of just two genera, Blakea and Topobea. Notable for their large, epiphytic habit, the ca. 200 species of Blakeeae are strictly neotropical, with centers of diversity in the middle elevation Colombian Andes and the mountains of Costa Rica and Panama. Most flowers in this tribe are large and showy, attracting a diversity of pollinators including various insects, birds, and most remarkably, rodents. The rodent pollination syndrome is exceedingly rare, and in the New World is known only from five species of Blakea (including Blakea chlorantha) and one Loasaceae. Mites and ants live in mutualistic associations in leaf and stem domatia of many Blakeeae. Many species in this group have great potential in the horticultural trade, are reasonably amenable to cultivation from seeds or cuttings, but are as yet underutilized.

Blakeeae is a monophyletic tribe (Clausing & Renner 2001; Renner et al. 2001; Michelangeli et al. 2004), and its two genera are primarily characterized by hemiepiphytic and epiphytic habits, presence of axillary, fasciculate inflorescences, large, 6-merous flowers each subtended by two pairs of decussate bracts, berry fruits, wood with multiseriate rays, and the frequent occurrence of druse crystals (Almeda 1990).

The morphological characters used to separate Blakea and Topobea all relate to the androecium. An examination of species exhibiting the “typical” character suites for each genus would, perhaps, provide justification for their separation, but a number of species intermediate in androecium characters have been discovered, eroding the already-dubious, and long-contested, distinctions between the genera (Don 1823; Naudin 1852; Triana 1871; Cogniaux 1891; Wurdack 1973, 1980). Typically, Blakea has twelve stamens, anthers that are oval, oblong, or elliptic, compressed laterally, bluntly obtuse or broadly rounded at the summit with two, typically well-separated apical pores. Topobea has six, eight, or twelve stamens, anthers that are linear-oblong to oblong-subulate or rostrate, usually not compressed laterally, with approximate or confluent, dorsally inclined pores.

Blakeeae were last given serious systematic consideration by Cogniaux (1891), and since that time the number of described species has quadrupled. This cladistic analysis seeks to end a longstanding debate over the recognition of Topobea and serve as a foundation for future monographic work by providing a well-supported hypothesis of phylogenetic relationships.

In my doctoral dissertation research to date, I have sequenced ca. 80 Blakeeae, plus 11 additional species from other tribes for ITS, accD-psaI, atpB-rbcL spacer region, trnL-F, and trnS-G. These preliminary results (in prep.) indicating that Huilaea is sister to Blakea + Topobea (and not a member of the Miconieae where it has traditionally been placed) were presented as a poster at the Botany2004 conference in Snowbird, Utah on August 3, 2004. I have also conducted a morphological cladistic analysis of the Blakeeae. A portion of the morphological matrix (complete character list here) provided below is a preliminary 'morphobank' concept demonstration that will be expanded later to allow interactive searches on the entire matrix.