Formerly known as Welfia georgii, this species of neotropical plant is part of the palm family, Arecaceae. The family is known as one of the largest group of monocotyledons, or monocots, characterized by disorganized vascular tissues which carry nutrients throughout the plant (Henderson 2006). This species is known as the Welfia palm, Palma Conga, Palmito, Amargo, and Camara. It is found from western Colombia to southern Nicaragua, in moist forests. It is most frequently found on the Atlantic coast, and in some areas is second in abundance only to Pentaclethra macroloba (Henderson et al. 1995). Like the rest of the palms, W. regia is a monocot, and therefore grows wide before tall so the disorganized vascular tissues develop enough to support the 8-20 m adult trunk. Other palm traits apparent in this species include compound pinnate leaves, a single, unbranched stem, and a cone of roots which support the tree. This palm species and many others grow a new leaf roughly every month with which grows a new flowering structure. The flowers are pollinated mainly by Trigona bees and Curculionid beetles. The fruits are eaten by many animals, but the seeds are dispersed entirely by birds.
Welfia regia has been found as far south as western Colombia through Panama, Costa Rica, and into southern Nicaragua at the most northern expanse (Henderson et al. 1995). In Costa Rica, it is rarely found in the southern Pacific lowlands of the Osa Peninsula, and the edges of the flat eastern lowlands (Henderson et al. 1995). It is extremely abundant in the Atlantic lowlands along the bases of the eastern faces of the Costa Rican mountains, between 0 and 1500 m in elevation (Henderson et al. 1995). Examples of the species' abundance can be found throughout the Sarapiquí watershed: in La Selva Biological Station and the Tirimbina Biological Reserve.
W. regia, a subcanopy palm (Wang & Augspurger 2006) requires areas of high rainfall in order to grow; therefore, it is completely absent in areas of high elevation or dry forest, such as the Costa Rican province of Guanacaste (Henderson et al. 1995). Adult individuals are capable of surviving in cleared areas, though juveniles and saplings will die. This species is abundant in forests with frequent formation of small light gaps, and is sometimes known as a "minor light gap" species due to its ability to thrive in such habitats (Henderson et al. 1995).
There are many fruit predators including kinkajous, squirrels, monkeys, and agoutis, which all have varying strategies for removing the ectocarp, eating the fleshy mesocarp and sometimes the seeds (Henderson et al. 1995). However, most of these fruit predators drop the seeds where they found the fruit: on or below the parent tree. This is not effective dispersal, as the dense canopy of the parent tree shades the seedlings and decreases the growth rate. In addition, falling heavy leaves of the parent tree crush and kill any seedlings, regardless of species, on which they land. Fortunately for the Welfia palm, the oily, sweet pulp of the fruit attracts many species of birds, which either drop or excrete the seed in a location away from the parent plant (Henderson et al. 1995).
Leaves of W. regia have been used for roof thatching and the trunks have been used in coastal areas as house pillars due to their rot resistance when exposed to salt water (Vandermeer 1983).
W. regia is distinguishable by its gray, spineless trunk, 8-20 m in height and 10-15 cm in diameter (Vandermeer 1983). The single stem is not branched, and is supported by a cone of roots. The leaves are compound pinnate, separating into 40-90 leaflets on each side of the rachis, which is the central branch-like appendage to which each leaflet connects (Vandermeer 1983). One tree holds anywhere between 10-30 leaves at a time, growing a new one roughly every month. The leaves grow upwards and droop down at the ends. They are about 3-6 m long and the leaf sheath, which surrounds the stem, is conspicuous (Vandermeer 1983).
The Welfia palm requires high rainfall and medium to high levels of light in order to grow (Henderson et al. 1995). They do well under the diffuse light of canopy coverage from large trees. W. regia’s shade tolerance allows the palm to grow wide first, unlike other canopy and subcanopy trees that sacrifice stability and safety in their race towards the canopy light (Montgomery & Chazdon 2001). This species grows well as an understory plant, but does even better as a canopy plant. This preference is visible when saplings grow in canopy light gaps. The growth and development is rapid, but slows if another plant grows into the gap and shades the Welfia sapling. Should another light gap open up, the rate of growth will speed up again, until the gap is filled. This pattern may continue with shifting light availability, though seedlings die if there is not enough constant light (Henderson et al. 1995). This is more likely to occur if the seedling grows directly under the shade of the dense canopy of its parent plant. Seedlings are also capable of dying as a result of parent leaves falling and crushing them (Henderson et al. 1995).
This species of palm goes through an establishment phase, during which the number of leaflets per leaf increases with age and light exposure (Henderson et al. 1995). The rate of increase in the number of leaflets is highly dependent on level of light quality. Also during this phase, the monocot is able to grow a wide trunk before it matures. When that happens, the leaflet number is at its maximum, the trunk is then growing up and not out, and the fruiting process begins (Vandermeer 1983). Another interesting aspect of this palm's development is a process called delayed greening. This process is a strategy which decreases herbivory of younger, more nutritious leaves by decreasing the amount of nutrient-filled, photosynthesizing chlorophyll in younger leaves until they are tougher and more resistant to insect and other leaf-eating animals or bacteria.
The flowering structure of W. regia, or inflorescence, is attached to the plant on a 10-15 cm long stem, called a peduncle (Vandermeer 1983). The inflorescence splits into 5-12 branches and is therefore a raceme (Vandermeer 1983). The branches of this raceme are 2.5-3.5 cm thick and pendulous, dangling down from the plant (Vandermeer 1983). Each branch is about 1 m long, with 8 vertical lines of numerous hollowed spaces, termed facets (Vandermeer 1983). Each facet contains four flowers, which bloom at different times, maximizing pollination potential (Henderson et al. 1995). The flowers are imperfect, containing only one sex of reproductive parts, and are described as male or female flowers. Because both male and female flowers occur on the same plant, this palm is monoecious. Of the four flowers in each facet, three are male and one is female. The white, male flowers bloom first and remain open for one day, displaying long anthers that hold easily accessible pollen (Vandermeer 1983). The pollen is transferred from individual to individual completing the process of pollination, as well as used by many insects as food. For approximately 10-15 days in a row, male flowers will bloom in an inflorescence. After a dormant period of 2-4 days, the female flowers will then all bloom simultaneously, and collect the pollen from male flowers of other individuals for an additional 2-4 days (Vandermeer 1983).
Two aspects of this flowering order are especially important to the pollination success of the plant. The order of bloom, male flowers then females, is called protandry and decreases the amount of self-pollination that occurs. Secondly, the female flowers look extremely similar to the male flowers, with petals that imitate the long, white, slender appearance of the anthers. This mimicry, or visual imitation, tricks pollinators into thinking they will receive pollen from the female flowers and incentivizes them to visit, thereby depositing pollen and completing the pollination process.
When the palm reaches adult height, about 8-20 m, they begin to fruit. Since each facet contains one female flower, one fruit will develop per facet. The period of time with the highest fruit fall occurs between July and September (Henderson et al. 1995). The fruit is almond shaped, between 3.5-4.5 cm long, 2 cm in diameter with a red to brown color (Vandermeer 1983). It consists of a nut surrounded by sweet, oily pulp and protected by a soft outer layer called the ectocarp. When the fruit are ripe, they fall to the ground to land just below the parent plant. Unless they are removed from the tree or the ground by animals, they will remain there to germinate and grow into seedlings.
This species of palm receives many species of insect visitors, the most frequent of which are bee species. The sting-less genus, Trigona, is the most popular bee pollinator of the Welfia Palm and completes the largest volume of plant pollination. A family of beetles, Curculionidae also pollinate the palm with frequency (Henderson et al. 1995). Due to their large range, Curculionid beetles contribute to the distance of which pollination occurs, and have been observed to carry pollen up to 300 m away from the parent plant (Henderson et al. 1995)
