''Hevea spruceana'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of rubber tree in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Hevea ''Hevea'' is a genus of flowering plants in the spurge family, Euphorbiaceae, with about ten members. It is also one of many names used commercially for the wood of the most economically important rubber tree, '' H. brasiliensis''. The genus is n ...

'', belonging to the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Euphorbiaceae Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as ''Euphorbia paralias'', are herbs, but some, e ...

. It is native to the rainforests of northern Brazil and Guyana. It is named in honour of the English botanist

Richard Spruce Richard Spruce (10 September 1817 – 28 December 1893) was an English botanist specializing in bryology. One of the great Victorian botanical explorers, Spruce spent 15 years exploring the Amazon from the Andes to its mouth, and was one of t ...

who spent the years 1849 to 1864 exploring the

Amazon basin The Amazon basin is the part of South America drained by the Amazon River and its tributaries. The Amazon drainage basin covers an area of about , or about 35.5 percent of the South American continent. It is located in the countries of Bolivi ...

and sending botanical specimens back to Europe.

Description

''H. spruceana'' is a medium-sized, evergreen tree that sometimes develops a markedly swollen trunk, seemingly a response to periodical flooding. The leaves have three elliptical leaflets. The inflorescence is a panicle with separate male and female flowers; in contrast to other members of the genus, the flowers of ''H. spruceana'' are purplish in colour. The usually three seeds are contained in a capsule with woody valves, but this does not break open explosively to expel the seeds as happens with other members of the genus.

Distribution and habitat

''H. spruceana'' is found in the Amazon basin, in a strip bordering the

Amazon River The Amazon River (, ; es, Río Amazonas, pt, Rio Amazonas) in South America is the largest river by discharge volume of water in the world, and the disputed longest river system in the world in comparison to the Nile. The headwaters of t ...

and some of its tributaries. Its range extends for the length of the Amazon from its confluence with the

Putumayo River The Putumayo River or Içá River ( es, Río Putumayo, pt, Rio Içá) is one of the tributaries of the Amazon River, southwest of and parallel to the Japurá River. Course The Putumayo River forms part of Colombia's border with Ecuador, as well ...

as far as the Amazon delta, almost extending to the sea. This tree also grows beside the lower reaches of the

Madeira River The Madeira River ( pt, Rio Madeira, link=no ) is a major waterway in South America. It is estimated to be in length, while the Madeira-Mamoré is estimated near or in length depending on the measuring party and their methods. The Madeira is ...

, the Rio Negro and other main Amazon tributaries. Its typical habitat is muddy islands and riverbanks in localities subject to frequent heavy flooding.

Ecology

When the forest is flooded, the fruits of ''H. spruceana'' ripen and fall into the water. They act as a magnet to tambaquis, large seed-eating fish in the

piranha A piranha or piraña (, , or ; or , ) is one of a number of freshwater fish in the family Serrasalmidae, or the subfamily Serrasalminae within the tetra family, Characidae in order Characiformes. These fish inhabit South American rivers, ...

family, which cluster around the trees, consuming every fruit that drops. The seeds are crushed by their powerful jaws but inevitably, some seeds pass through the fish undamaged and are dispersed elsewhere. Two other members of the piranha family that also feed on the fruits are '' Serrasalmus serrulatus'' and '' Pristobrycon striolatus''. These fish are more selective, peeling the seeds and discarding the skins before breaking up and swallowing the kernels. Other fish that invade the flooded forest and are found near ''H. spruceana'' are the flesh-eating

piranhas A piranha or piraña (, , or ; or , ) is one of a number of freshwater fish in the family Serrasalmidae, or the subfamily Serrasalminae within the tetra family, Characidae in order Characiformes. These fish inhabit South American rivers, ...

, which feed on other fish, insects, birds and animals that have fallen into the water, sometimes supplementing this diet with the fruits and seeds of the rubber tree.

References

{{Taxonbar, from=Q15392539 Trees of Brazil Trees of the Amazon Crotonoideae