Scans of Neotropical Loranthaceae & friends
posted February 17th, 2012
Loranthaceae is the original family of Mistletoes, mostly robust woody shrubs and vines that parasitize other trees, and sometimes even each other. Some are terrestrial, parasitizing root systems and others grow directly on the branches of the host. The thick green leaves have a rubbery look, and a tendency to break up like peanut brittle when dried as herbarium specimens. The flowers of some species are spectacular, red, and bird-pollinated, while in others they look like barnacles.
Recent treatments of the family have confirmed the need to move several genera, including the Christmas mistletoe, into the vicinity of the Sandalwood family (Santalaceae). The displaced genera include Antidaphne, Eubrachion & Lepidoceras ("Eremolepidaceae"), and Arceuthobium, Dendrophthora & Phoradendron ("Viscaceae"). Controversy remains whether the Sandalwood family should be one big diverse family, or a lot of little families. In the herbarium, these genera remain for now in the Loranthaceae, due to the unfortunate mass density of objects relative to concepts.
In 2010, Kathryn and I pulled a mountain of "Loranthaceae" (old-fashioned sense) species from the Main Herbarium to scan, trying to get as many represented on our website as possible. The Canadian botanist Job Kuijt has been in deep communion with this family for over 50 years, and we're lucky to have had him visit Field Museum many times to study our specimens. The Loranthaceae et al. is not a family we would want to tackle ourselves. In recent years, he's published monographs of the large genera Phoradendron (Viscaceae/Santalaceae, 2003), and Psittacanthus (Loranthaceae, 2009), as well as the Caribbean endemic Dendropemon (Loranthaceae, 2011), so we checked our Phoradendron and Psittacanthus specimens against the recent specimen lists, and we're happy to have these fairly up-to-date.
Also, we've updated our scans to reflect the recent remodeling of the genus Phthirusa (Kuijt 2011). Most of the species of that genus, are now moved into the genus Passovia, a name that has been dormant for about 100 years. Meanwhile the small genus Ixocactus turns out to be the REAL Phthirusa, and its seven species are all moved back into Phthirusa. .... Kuijt provides names in the appropriate genus for most species involved, but because the "old" genus Phthirusa is still so poorly understood, some of the lesser-known "Phthirusa" names are left in limbo.
One exciting accidental finding in passing through the Loranthaceae, was a new country record for the genus Eubrachion ("Eremolepidaceae"). Browsing the pile of unidentified material filed at the end of the family, I found two specimens from Imbabura, Ecuador, collected in 1949, which matched the north Venezuelan species Eubrachion gracile. Scans were sent to Dr. Kuijt, who confirmed the ID, which he called "totally unexpected!" The Ecuadorean collector noted that the plant was called "mata palo," a lethal parasite on arrayán, a tree of the Myrtaceae family. .....The collector, incidentally, Dr. Misael Acosta Solis, was an Ecuadorean botanist and passionate conservationist ahead of his time, who visited the Field Museum in 1947-48 for help identifying his plants, and later provided us with many valuable duplicates.
Kuijt, J. & E.A. Kellogg. 1996. Miscellaneous mistletoe notes, 20-36. Novon 6: 33-53. [for synonymy of Phthirusa stelis, now Passovia stelis]
Kuijt, J. 2003. Monograph of Phoradendron (Viscaceae). Syst. Bot. Monogr. 66.
Kuijt, J. 2009. Monograph of Psittacanthus (Loranthaceae). Syst. Bot. Monogr. 86.
Kuijt, J. 2011. Pulling the skeleton out of the closet: resurrection of Phthirusa sensu Martius and consequent revival of Passovia. Plant Div. Evol. 129: 159-211.
Kuijt, J. 2011. Monograph of Dendropemon (Loranthaceae). Syst. Bot. Monogr. 92.