EPOW - Ecology Picture of the Week

Patujú Gigante (Phenakospermum guianensis [or guyanense])
Family Strelitziaceae (prev. included in Musaceae), Order Zingiberales
Upper Amazon Basin, northeastern Bolivia

Explanation:  Stretching into a gap in the tropical forest canopy overhead is this "traveler's palm" ... also known locally as patujú gigante in Bolivia or sororoca in neighboring Brazil.  We are in the Upper Amazon Basin in extreme northeast Bolivia near Rio Paragua and the border with Brazil, exploring a remote timber concession.  

Patujú gigante is actually a gigantic herb, which can form large dense stands.  It grows here in disturbed sites, where road-building or logging activities have at least partially opened the forest canopy, or where secondary forests are regrowing after timber harvest.  In northwestern Bolivia, patujú gigante is known to occur in transitional forest sites between old growth Amazonian forests and savanna vegetation.  In a study in northeast Bolivia, Gosling and others (2005) found that patujú gigante was one of the most frequently encountered plants in upland forests although it did not appear in pollen samples.  

This plant is part of the botanical family Strelitziaceae (which some botanists include in the banana family Musaceae because of similarity of the growth form).

The global distribution of the family Strelitziaceae is most interesting.  It is disjunct and widely separated in the southern hemisphere ... occurring in the Amazon Basin of South America, extreme southern Africa, and Madagascar.  Such a distribution suggests that the family is very ancient and once occupied Gondwana, the southern super-continent that eventually split under tectonic forces and continental drift.  Under such isolation, members of this family diverged into three genera and seven species, including this traveler's palm (Phenakospermum guianensis) in the Amazon, the bird-of-paradise (Strelitzia spp.) in South Africa, and another traveler's palm (Ravenala madagascariensis) found only on Madagascar.  

According to one source, the indigenous Nukak people that live in the Upper Amazon Basin of Columbia find great value from patujú gigante.  They collect its fruits to eat and its leaves for roofing cover.   

Studies of bats in Brazil suggest that patujú gigante might be used there as roost sites by "disc-winged" bats of the genus Thyroptera, which might cling to the underside of the large leaves with suction cup-like discs on its wings.  

Acknowledgments:
     My thanks to Betty Flores, the Bolivian ornithologist shown in this week's image, for hosting me in the field.  Thanks also to biologist Damian Rumiz for confirming identification of this plant species.

Information:
     Gosling, W. D., F. E. Mayle, N. J. Tate, and T. J. Killeen. 2005. Modern pollen-rain characteristics of tall terra firme moist evergreen forest, southern Amazonia. Quaternary Research 64:284-297.
     Shapley, R. L. 2000. Preliminary results of a technical visit to survey the bat species present in Jaú National Park, Amazonas, Brazil, 18 October to 11 November, 2000. No. 3 of the Igapó Study Project Report Series. Fundação Vitória Amazônica, Manaus, Brazil. 10 pp.