''Pentaclethra macroloba'' is a large and common

leguminous A legume () is a plant in the family Fabaceae (or Leguminosae), or the fruit or seed of such a plant. When used as a dry grain, the seed is also called a pulse. Legumes are grown agriculturally, primarily for human consumption, for livestock for ...

tree in the genus ''

Pentaclethra ''Pentaclethra'' is a small genus of trees from the tropics. They are flowering plants in the family Fabaceae. They belong to the mimosoid clade of the subfamily Caesalpinioideae. The name ''Pentaclethra'' is derived from Ancient Greek, ''penta ...

'' native to the wet tropical areas of the northern

Neotropics The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone. Definition In bioge ...

, which can form monocultural stands in some seasonally flooded

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s. It has giant,

bipinnate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular ...

leaves shaped like feathers. It uses seed dispersal by water to establish itself in new areas, having floating seeds that are left behind after the waters recede after floods or tides. It has hard

timber Lumber is wood that has been processed into dimensional lumber, including beams and planks or boards, a stage in the process of wood production. Lumber is mainly used for construction framing, as well as finishing (floors, wall panels, w ...

which is not very resistant to rot in the tropics, but it can be treated, has a pretty pink-red colour when dry, and has a number of uses. Oil used in cosmetics is extracted from the large seeds. In the northern

Amazon Amazon most often refers to: * Amazons, a tribe of female warriors in Greek mythology * Amazon rainforest, a rainforest covering most of the Amazon basin * Amazon River, in South America * Amazon (company), an American multinational technolog ...

region the bark is used in

herbal medicine Herbal medicine (also herbalism) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. With worldwide research into pharmacology, some herbal medicines have been translated into modern remedie ...

as an antivenom, and in the

Guianas The Guianas, sometimes called by the Spanish loan-word ''Guayanas'' (''Las Guayanas''), is a region in north-eastern South America which includes the following three territories: * French Guiana, an overseas department and region of France * ...

the bark has been used as a

fish poison Fish toxins or fish stupefying plants have historically been used by many hunter gatherer cultures to stun fish, so they become easy to collect by hand. Some of these toxins paralyse fish, which can then be easily collected. The process of documen ...

. Despite their toxicity, the seeds are eaten by

variegated squirrel The variegated squirrel (''Sciurus variegatoides'') is a tree squirrel in the genus '' Sciurus'' found in Costa Rica, El Salvador, Guatemala, Honduras, southern Mexico, Nicaragua, and Panama. Fifteen subspecies are recognised. It is a comm ...

parrot Parrots, also known as psittacines (), are birds of the roughly 398 species in 92 genera comprising the order Psittaciformes (), found mostly in tropical and subtropical regions. The order is subdivided into three superfamilies: the Psittacoide ...

s and

macaw Macaws are a group of New World parrots that are long-tailed and often colorful. They are popular in aviculture or as companion parrots, although there are conservation concerns about several species in the wild. Biology Of the many differ ...

s, and serve as the nurseries of the larvae of the moth ''

Carmenta surinamensis ''Carmenta surinamensis'' is a moth of the family Sesiidae. It was described by Heinrich Benno Möschler in 1878, and is known from Brazil, Suriname, Guyana, Trinidad, Panama and Costa Rica. The larvae of the species have been found on seeds o ...

''.

Etymology and local names

The name ''Pentaclethra'' is derived from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic pe ...

, ''penta'' meaning 'five', and ''cleithro'' meaning 'bolt', which alludes to the five imbricate sepals and five petals joined at their bases; this defines the species of the genus. The tree is popularly known as ''pracaxi'' in the Amazon region of Brazil. In the

Arawak language Arawak (, ), also known as Lokono (Lokono Dian, literally "people's talk" by its speakers), is an Arawakan language spoken by the Lokono (Arawak) people of South America in eastern Venezuela, Guyana, Suriname, and French Guiana. It is the epony ...

it is known as ''koroballi'', in

Sranantongo Sranan Tongo (also Sranantongo "Surinamese tongue," Sranan, Surinaams, Surinamese, Surinamese Creole) is an English-based creole language that is spoken as a ''lingua franca'' by approximately 550,000 people in Suriname. Developed originally am ...

it is called ''kroebara''. In

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many Latin American countries **Spanish cuisine Other places * Spanish, Ontario, Can ...

it is called ''gavilán'' or ''quebracho''.

Description

''Pentaclethra macroloba'' is a tree which can vary in height and size depending on distribution. In Costa Rica it grows to the greatest dimensions and is usually a

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an ...

tree which reaches a trunk diameter of , and heights of . In Brazil the average height is said to be approximately , and in the eastern Guianas it is said to grow up to . In these areas it is a subcanopy tree. This may be due to infraspecific variation. The canopy or crown is dense and broad. The twigs are brownish-red, when they are young they are covered in a puberulous

indumentum In biology, an indumentum (Latin, literally: "garment") is a covering of trichomes (fine "hairs") on a plant Davis, Peter Hadland and Heywood, Vernon Hilton (1963) ''Principles of angiosperm taxonomy'' Van Nostrandpage, Princeton, New Jersey, pa ...

. The twigs are without spines. The 0.7–0.8 cm

stipule In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...

s are deciduous, linear or hair-like.

Leaves

Pentaclethra macroloba, foliage of the Gavilan tree

The large leaves are twice compound, arranged in a spiral on the stems. The leaf blades, which can be up to long, consist of 15 to 20 pairs of first-order pinnae long, alternately placed on a cylindrical

rachis In biology, a rachis (from the grc, ῥάχις [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this c ...

. The petiole is 1–5 cm long, the main rachis is 11–30 cm, when young they are covered in a brown puberulous indumentum. The rachis is angular in profile, and grooved longitudinally on the upper side. The rachillae hava a 1mm-long hinge. There are 30 to 50 pairs of second-order leaflets which are leathery in texture, narrowly falcate, with a

pilose Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a plan ...

glabrescent Glabrousness (from the Latin ''glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part ...

indumentum, and multiple linear ribs. Among mimosoids, ''Pentaclethra'' are unusual in that they lack nectar glands on the rachis, or anywhere on the leaves.

Flowers

The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are forme ...

is a 10 to 25 cm, most often 20 cm long spike, with approximately 320 flowers, each one perfect and complete (containing all the functional male and female parts). The rachis is 15–20 cm long and has 1–5 cm peduncle. The spikes are terminal or subterminal on the branches. Developing spikes are covered in a reddish-brown pubescence. The about 2 cm sessile flower has five petals and is

actinomorphic Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts. Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirall ...

. It is scented. The greenish-brown

calyx Calyx or calyce (plural "calyces"), from the Latin ''calix'' which itself comes from the Ancient Greek ''κάλυξ'' (''kálux'') meaning "husk" or "pod", may refer to: Biology * Calyx (anatomy), collective name for several cup-like structures ...

gamosepalous A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

with the sepals being imbricate (having overlapping edges), and about 2 cm long with a joint base and five free lacinia (narrowly-incised segments between them). The

corolla Corolla may refer to: *Corolla (botany), the petals of a flower, considered as a unit *Toyota Corolla, an automobile model name *Corolla (headgear) A ''corolla'' is an ancient headdress in the form of a small circlet or crown.connate) petals. A Brazilian study found the petals are uniformly dark red at the base and yellow at the apex in their specimens. A Costa Rican document describes them as purple, becoming greenish towards their tips. There are ten free

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the fila ...

s, about 7mm long, arranged in two distinct groups (a 'heteromorphic'

androecium The stamen ( plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the fil ...

). Their

anther The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filam ...

s carry a conspicuous apical gland and five long (2.5 cm), white staminodes, which have filaments with a small appendage at their terminal ends. The anthers are dorsifixed -this means a pair are fused together along their sides, like two hot-dog buns stuck together, with the filament attached to the centre of the pair. The anthers open longitudinally when they mature and dry, dispersing

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametop ...

grains as monads. The female part of the flower has a single

carpel Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) '' pistils' ...

capped by a chamber-like shaped stigma, this carpel has an unilocular

ovary The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. ...

containing about eight ovules in its upper portion. There is a disc-shaped

nectary Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualist ...

at the base of the ovary. The apical gland mentioned above is a rather unique and mysterious anatomical feature found only in the anthers of mimosids and related legumes. Such glands occur in four distinct forms, and the ''

'' form is unique to this genus, distinguished by a

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

furrow in the middle of the anther, and a

ventral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

conical structure similar to a food body or an osmophore.

Fruit, seeds and seedlings

Despite producing hundreds of flowers per inflorescence, each spike only produces a few fruit, which is a pod (or bean). These are held erect above the foliage and branches. The pod is (16.1-) 30 to 38 (-45.2)cm in length, (3.3-) 4.1 to 6 (-7.3)cm in width, and 0.8 to 1.1 cm thick. It is coloured greenish when fresh, and dark brownish-grey when dry. The shape is falcate or linear-spatulate and flattened, with the greatest width above the middle, the base being attenuated truncate and the apex being rounded. The pod is woody, and it opens by elastic dehiscence from the apex to the base. It has longitudinal veins. The dorsal suture is up to 1.1 cm broad and thickened, the ventral suture is up to 0.8 cm thick. As the seedpod dried tension builds until the two valves twist open suddenly when the suture cracks open. The pod has three to eight seeds, more often four to six. The large and flat seeds measure from 3.8 to 5 cm, exceptionally 6.1 cm, in length, and 2.5 to 3.5 cm, exceptionally 5.7 cm in width. The form is lens-like to spoon-shaped or deltoid, or ovoid to elliptical, and laterally flattened. They are coloured dark brown. The seeds do not have arils. The

cotyledon A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The numb ...

s are composed anatomically of thin-walled

parenchyma Parenchyma () is the bulk of functional substance in an animal organ or structure such as a tumour. In zoology it is the name for the tissue that fills the interior of flatworms. Etymology The term ''parenchyma'' is New Latin from the word � ...

cells with various oil cells. When the seeds

germinate Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, fer ...

, thick and large, green-coloured cotyledons open at the soil surface, and send up a shoot, called the

epicotyl An epicotyl is important for the beginning stages of a plant's life. It is the region of a seedling stem above the stalks of the seed leaves of an embryo plant. It grows rapidly, showing hypogeal germination, and extends the stem above the soil surf ...

. The cotyledons remain attached to the seedlings and serve as energy reserves for the growing plant. The epicotyl is slightly twisted, it first grows

cataphyll In plant morphology, a cataphyll (sometimes also called a ''cataphyllum'' or cataphyll leafJackson, Benjamin, Daydon; A Glossary of Botanic Terms with their Derivation and Accent; Published by Gerald Duckworth & Co. London, 4th ed 1928) is a reduc ...

s that wither and are shed early in the development, and then bears a first pair of alternate eophylls, before developing bipinnate leaves, with leaflets that have waxes and simple

trichome Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a p ...

s on their upper surface at the margins, and

stomata In botany, a stoma (from Greek ''στόμα'', "mouth", plural "stomata"), also called a stomate (plural "stomates"), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is b ...

on the bottom surface.

Similar species

The plant can be recognised as belonging to this species by: not having any spines, bipinnate leaves without nectar glands, inflorescences as large spikes covered in conspicuous white stingy staminodes, and fruit held above the branches, in the shape of a machete, which open with an elastically explosive mechanism from the apex to the base. Its large seeds are recognisable by their more or less lens-like to spoon-shaped form. Taxonomic recognition of saplings of this species is possible in the field through the morphology.

Distribution

According to one 1983 source, it exists in three disjunct populations, one through the lowlands of northeast

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

through the

, including

Trinidad and Tobago Trinidad and Tobago (, ), officially the Republic of Trinidad and Tobago, is the southernmost island country in the Caribbean. Consisting of the main islands Trinidad and Tobago, and numerous much smaller islands, it is situated south of ...

. The second population occurs in western

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the ...

and

Darien Province Darien may refer to: Places Central America * Darién Gap, break in the Pan-American Highway between Colombia and Panama * Darién National Park * Darién Province * Gulf of Darién * "... a peak in Darien", phrase in Keats's poem "On First Lo ...

in eastern Panama. The third is found in western Panama,

Costa Rica Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the no ...

and

Nicaragua Nicaragua (; ), officially the Republic of Nicaragua (), is the largest country in Central America, bordered by Honduras to the north, the Caribbean to the east, Costa Rica to the south, and the Pacific Ocean to the west. Managua is the coun ...

. Another source considers it introduced to Trinidad and Tobago and the

Windward Islands french: Îles du Vent , image_name = , image_caption = ''Political'' Windward Islands. Clockwise: Dominica, Martinique, Saint Lucia, Saint Vincent and the Grenadines, and Grenada. , image_alt = , locator_map = , location = Caribbean Sea No ...

. In Costa Rica and Nicaragua it primarily grows along the eastern coasts. It does not occur in western Nicaragua. The populations in Costa Rica are not disjunct, as it occurs through the central valleys and in certain patches on the western coast. In eastern Panama it is the dominant tree in certain moist, seasonal, swamp forests in coastal areas of the Atlantic. It has been collected in

Bocas del Toro Bocas del Toro (; meaning "Mouth of the Bull") is a province of Panama. Its area is 4,643.9 square kilometers, comprising the mainland and nine main islands. The province consists of the Bocas del Toro Archipelago, Bahía Almirante (Almirante Bay ...

and

Darién Province Darién (, , ) is a province in Panama whose capital city is La Palma. With an area of , it is located at the eastern end of the country and bordered to the north by the province of Panamá and the region of Kuna Yala. To the south, it is bord ...

. In Colombia it is only found along the Pacific coast. It is a common tree in northern parts of

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. It is found in the states of

Acre The acre is a unit of land area used in the imperial and US customary systems. It is traditionally defined as the area of one chain by one furlong (66 by 660 feet), which is exactly equal to 10 square chains, of a square mile, 4,840 square ...

, Amazonas,

Amapá Amapá () is one of the 26 states of Brazil. It is in the northern region of Brazil. It is the second least populous state and the eighteenth largest by area. Located in the far northern part of the country, Amapá is bordered clockwise by Fr ...

Pará Pará is a state of Brazil, located in northern Brazil and traversed by the lower Amazon River. It borders the Brazilian states of Amapá, Maranhão, Tocantins, Mato Grosso, Amazonas and Roraima. To the northwest are the borders of Guyana a ...

and

Roraima Roraima (, ) is one of the 26 states of Brazil. Located in the country's North Region, it is the northernmost and most geographically and logistically isolated state in Brazil. It is bordered by the state of Pará to the southeast, Amazonas ...

, and perhaps in the state of

Mato Grosso Mato Grosso ( – lit. "Thick Bush") is one of the states of Brazil, the third largest by area, located in the Central-West region. The state has 1.66% of the Brazilian population and is responsible for 1.9% of the Brazilian GDP. Neighboring ...

. In the 1993 article ''Catalogue of the Flowering Plants and Gymnosperms of Peru'' it was said to occur in the Department of Loreto. This was however based on a voucher specimen, which although having been determined to be ''P. macroloba'' in 1993, was re-identified as the species '' Dimorphandra coccinea'' in 1997.

Ecology

It grows in lowland forest from sea level to 600 metres above sea level in Costa Rica, and is especially abundant in humid, temporarily inundated

rainforest Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores ...

s. It is restricted to the lowlands in Panama. It occurs at an altitude of 0-290m in Colombia. In Brazil it is known from the seasonally flooded, closed tropical rainforests known as ''várzea'', in both '' igapó'' (inundated forest)

and forest on 'terra firme' land. In the Brazilian

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 ...

estuary it is the 'hyperdominant' lifeform, forming vast monospecific stands. In the Amazon River estuary the plants are subjected to daily tides. In the wooded floodplains of Mazagão, Brazil, the population density was 18 trees per hectare with a basal area of 49 m2 per hectare. In La Selva Biological Station ''Pentaclethra macroloba'' constitutes 40% of the basal area and up to 18% of the stem density in parts of the forest, where it forms monocultural stands. Different trees synchronize their flowering in the dry season. In Costa Rica flowering starts in March. It is the conspicuous white staminodes which attract

pollinator A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains. Insects are the m ...

s, not the minute petals. It is cross-pollinated. The main visitors to the flowers are wasps, bees and ants. Immature fruits appear during the dry season and ripe fruits in the rainy season. The species is

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

, showing no specific changes in the leaves throughout the year, despite flooding. The tree uses at least three methods of

seed dispersal In Spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vector ...

. Seeds are mechanically dispersed when mature pods split, popping open during the rainfall. The mechanism works by elastic dehiscence. The seeds are expelled up to ten meters from the parent tree. This is the season when rivers overflow their banks, and the lowland floods. In 2001 the discovery was published that submerged seeds develop air pockets that allow them to float; this was then interpreted as evidence that the species has adaptions for dispersal by water (hydrochory). Dispersal of seeds during daily river flooding and at the peak of the river flood allows the plant to use the receding waters of the tides to transport them long distances. The population density increases with the distance from the normal edge of the inundation. This is believed to be due to the action of the floodwaters during high tide, the floating seeds end up stuck behind fallen branches,

buttress root Buttress roots also known as plank roots are large, wide roots on all sides of a shallowly rooted tree. Typically, they are found in nutrient-poor tropical forest soils that may not be very deep. They prevent the tree from falling over (hen ...

s or other objects, often in great numbers. Like many leguminous plants, ''P. macroloba'' is a nitrogen fixer which forms a symbiotic relationship with ''

Rhizobium ''Rhizobium'' is a genus of Gram-negative soil bacteria that fix nitrogen. ''Rhizobium'' species form an endosymbiotic nitrogen-fixing association with roots of (primarily) legumes and other flowering plants. The bacteria colonize plant cells ...

'', which grows in specialised

root nodule Root nodules are found on the roots of plants, primarily legumes, that form a symbiosis with nitrogen-fixing bacteria. Under nitrogen-limiting conditions, capable plants form a symbiotic relationship with a host-specific strain of bacteria known a ...

s. While root nodules are typically found on buried roots, ''P. macroloba'' individuals growing in swampy areas produce nodules on

aerial root Aerial roots are roots above the ground. They are almost always adventitious. They are found in diverse plant species, including epiphytes such as orchids (''Orchidaceae''), tropical coastal swamp trees such as mangroves, banyan figs (''Fic ...

Seed predation

Gary Hartshorn, a

forester A forester is a person who practises forestry, the science, art, and profession of managing forests. Foresters engage in a broad range of activities including ecological restoration and management of protected areas. Foresters manage forests to ...

at the US

World Forestry Center The World Forestry Center is a nonprofit educational institution in Portland in the U.S. state of Oregon. Located near the Oregon Zoo in Washington Park, the organization was established in 1964 as the Western Forestry Center, with the actual b ...

at the time, wrote an account on the species in the 1983 book ''Costa Rican Natural History'', in which he principally theorised as to how the species had become so dominant in the monocultural forests of La Selva Biological Station. The seeds and seedling are conspicuously abundant on the forest floor. One of his assertions was that the seeds are so well-protected by their toxin defences, that they are able to withstand significant

seed predation Seed predation, often referred to as granivory, is a type of plant-animal interaction in which granivores (seed predators) feed on the seeds of plants as a main or exclusive food source,Hulme, P.E. and Benkman, C.W. (2002) "Granivory", pp. 13 ...

. The seeds are quite poisonous, containing toxic

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of simila ...

s and special amino acids. Possibly the most common rodent in the ''Pentaclethra'' forests is the spiny pocket mouse ''

Heteromys desmarestianus Desmarest's spiny pocket mouse (''Heteromys desmarestianus'') is a species of rodent in the family Heteromyidae. It is found in Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama Panama ( , ; es, lin ...

''. An experiment where the mice were exclusively fed the seeds killed them all. Hartshorn noted the presence of the larvae of a wasp-like, clear-winged moth feeding in the seeds, but noted that their presence did not impede germination, and speculated that the opening of the

s at the surface of the soil was perhaps a defensive tactic of the plant, as it exposes the caterpillars to foraging ground insectivores. The seeds are actually heavily predated upon, frequently ten or eleven insect larvae emerge through small holes on the exposed surface of the opened cotyledons. This appears to be primarily caused by the moth ''

'', which was found in 43.6% of the seeds in one study in Costa Rica. This reduces their viability, but does not always kill them. Hartshorn himself had noted in his earlier thesis paper that grey squirrels ('' Sciurus variegatoides'') and white-crowned parrots ('' Pionus senilis'') feed upon the seeds up in the trees while still in the unopened pods. The animals access the seeds by making a hole in one valve of these pods. A small study which looked at 100 pods found that 22% of the fruit had such holes in them. The animals rarely get all the seeds, but often just take one or few from a pod. Only 5% of the total seed production is consumed before the pods open. These are taken in a rather random manner, with no particular selection apparent. An explanation for this may be that the preferences of the squirrels and parrots are precisely diametrically opposed and they might cancel each other out, but it is also possible that the optimal foraging theory, which would have it that predators select the biggest and easiest to forage seeds, may not apply here, as both animals may be able to tolerate some toxins, they are still susceptible to them, and must limit their intake. The pod damage may hinder the elastic mechanism that flings the seeds away from the tree, thus 22% the pod predation may still be quite significant for the

population dynamics Population dynamics is the type of mathematics used to model and study the size and age composition of populations as dynamical systems. History Population dynamics has traditionally been the dominant branch of mathematical biology, which has a ...

Great green macaw The great green macaw (''Ara ambiguus''), also known as Buffon's macaw or the great military macaw, is a Central and South American parrot found in Nicaragua, Honduras, Costa Rica, Panama, Colombia and Ecuador. Two allopatric subspecies are rec ...

s have also been recorded to feed on the seeds. Capuchin monkeys have a strange and mysterious behaviour, known as 'anointing', in which they periodically rub their bodies with specific objects. On Trinidad the small population of

white-fronted capuchin White-fronted capuchin can refer to any of a number of species of gracile capuchin monkey which used to be considered as the single species ''Cebus albifrons''. White-fronted capuchins are found in seven different countries in South America: Bo ...

s at Bush Bush Wildlife Sanctuary use the pods of ''P. macroloba'' to anoint themselves. They pluck a pod from the tree, break it open, and rub themselves with the inner part. These Trinidadian monkeys do this often, and always do it in sight of each other. Afterwards they often eat one or more of the seeds found inside the pod, whether these are ripe or not. Other monkeys avoid the bark and seeds of ''P. macroloba''. Perhaps the monkeys use the seedpods as a curative, or some kind of medicine.

Phytosociology

In Mazagão, Brazil, it is found growing together with a high frequency of palms and the trees '' Carapa guianensis'', ''

Virola surinamensis ''Virola surinamensis'', known commonly as baboonwood, ucuuba, ucuhuba and ''chalviande'',Americas Regional Workshop (Conservation & Sustainable Management of Trees, Costa Rica, November 1996). 1998''Virola surinamensis''.The IUCN Red List of Thr ...

'', ''

Mora paraensis Mora may refer to: People * Mora (surname) Places Sweden * Mora, Säter, Sweden * Mora, Sweden, the seat of Mora Municipality * Mora Municipality, Sweden United States * Mora, Louisiana, an unincorporated community * Mora, Minnesota, a city * ...

'', '' Calycophyllum spruceanum'', ''

Hevea brasiliensis ''Hevea brasiliensis'', the Pará rubber tree, ''sharinga'' tree, seringueira, or most commonly, rubber tree or rubber plant, is a flowering plant belonging to the spurge family Euphorbiaceae originally native to the Amazon basin, but is now pa ...

'', '' Platymiscium ulei'', a ''

Licania ''Licania'' is a genus of over 200 species of trees and shrubs in the family Chrysobalanaceae. Species are found naturally occurring in Neotropical forests from southern Mexico to Brazil and the Lesser Antilles. Due to increased deforestation and ...

'' species, ''

Cedrela odorata ''Cedrela odorata'' is a commercially important species of tree in the chinaberry family, Meliaceae, commonly known as Spanish cedar or Cuban cedar; it is also known as cedro in Spanish. Classification The genus ''Cedrela'' has undergone two m ...

'', '' Pterocarpus amazonicus'', ''

Symphonia globulifera ''Symphonia globulifera'', commonly known as boarwood, is a timber tree abundant in Central America, the Caribbean, South America and Africa. This plant is also used as a medicinal plant and ornamental plant. Common names Common trade names of t ...

'', '' Licaria mahuba'', ''

Hernandia guianensis ''Hernandia'' is a genus of flowering plants in the family Hernandiaceae. It was named after the Spanish botanist Francisco Hernández de Toledo. Species , ''Plants of the World Online'' accepted the following species: * ''Hernandia albiflora'' ...

'' and others. It is a common tree in the '' Mora excelsa'' forests of the Guianas and the

Orinoco The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers , with 76.3 percent of it in Venezuela and the remainder in Colombia. It is the fourth largest river in the wor ...

Delta of Venezuela, in this habitat the ''Mora'' is the dominant species, and ''Pentaclethra'' is a subcanopy tree. In Central America the species is the dominant canopy tree, growing with '' Carapa guianensis'' subdominant in the canopy, and also associated with the palms '' Astrocaryum alatum'' and '' Iriartea gigantea'', and the trees '' Pterocarpus officinalis'' and '' Stryphnodendron microstachyum''.

Uses

Timber

The sapwood of the tree is whitish, drying to pink, while the

heartwood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin t ...

is reddish brown. The timber has a

specific gravity Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its dens ...

of 0.51–0.61. The timber has commercial value. It is used to make furniture, cabinets and for general construction. The timber is traded as 'gavilán'.

Other

Pracaxi oil, which is extracted from the seeds of ''P. macroloba'', is rich in oleic, linoleic, and

behenic acid Behenic acid (also docosanoic acid) is a carboxylic acid, the saturated fatty acid with formula C21H43COOH. In appearance, it consists of white solid although impure samples appear yellowish. Sources At 9%, it is a major component of ben oil (or ...

. It is used as a replacement for synthetic hair conditioners in 'green' cosmetics. Both the bark and seed oil contain the possibly toxic

paucine. Paucine (

caffeoyl Caffeic acid is an organic compound that is classified as a hydroxycinnamic acid. This yellow solid consists of both phenolic and acrylic functional groups. It is found in all plants because it is an intermediate in the biosynthesis of lignin, on ...

putrescine Putrescine is an organic compound with the formula (CH2)4(NH2)2. It is a colorless solid that melts near room temperature. It is classified as a diamine. Together with cadaverine, it is largely responsible for the foul odor of putrefying flesh ...

) is a growth-retardant. In

Nigeria Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf o ...

the seed of the related African species ''P. macrophylla'' is boiled and fermented with ''

Bacillus subtilis ''Bacillus subtilis'', known also as the hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium, found in soil and the gastrointestinal tract of ruminants, humans and marine sponges. As a member of the genus ''Bacillus ...

'', which detoxifies it of paucine. In the Guianas the poisonous bark is used as a

. Traditional medicinal properties ascribed to this plant species by ''caboclos'' (Brazilian Portuguese for 'locals') and various native groups are as an antivenom against snakebites, and as a curative for ulcers and insect bites. For snakebites, the dried bark is macerated and applied as a paste to the site of the bite. When Brazilian scientists tested an extract from the dried bark to see if any antivenom effect could be detected, it showed a measurable ability to reduce haemorrhaging ''

in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, and p ...

'' when mixed with the venom and injected into mice. Although plant-based antivenoms are used by many cultures around the world, few have actually been shown to have any positive effect. Because

electrophoresis Electrophoresis, from Ancient Greek ἤλεκτρον (ḗlektron, "amber") and φόρησις (phórēsis, "the act of bearing"), is the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric fi ...

showed that the snake venoms were not being degraded by the extract, which eliminated

proteolytic Proteolysis is the breakdown of proteins into smaller polypeptides or amino acids. Uncatalysed, the hydrolysis of peptide bonds is extremely slow, taking hundreds of years. Proteolysis is typically catalysed by cellular enzymes called prote ...

enzymatic activity as the mechanism of action, the Brazilian scientists hypothesised that the effect was caused by an unknown substance with some kind of inhibitory action caused by the binding of the

zinc Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...

ions required by snake venom metalloproteases to function. Snake venom is a complex mixture of toxic chemicals, however, and not all components of the venoms tested were neutralised. Two years later many of the same researchers had a new article published; this time they had isolated the compounds causing the protective effect, two

triterpenoid Triterpenes are a class of chemical compounds composed of three terpene units with the molecular formula C30H48; they may also be thought of as consisting of six isoprene units. Animals, plants and fungi all produce triterpenes, including squal ...

saponin Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...

s which they named macrolobin-A and B. Although these compounds do not fully counteract all the venomous effects, they could find use as complements to standard treatment against snakebites, or as molecular models for the development of novel future medicinal compounds.

Conservation

It is a common species where it occurs in the Guianas and Central America.

References

{{Taxonbar, from=Q17466932 Mimosoids Flora of northern South America Flora of Colombia Flora of Central America Flora of Brazil Flora of Trinidad and Tobago Flora without expected TNC conservation status