Cecropia
Cecropia is a Neotropical genus consisting of 61 recognized species with a highly distinctive lineage of dioecious trees. The genus consists of pioneer trees in the more or less humid parts of the Neotropics, with the majority of the species being myrmecophytic. Berg and Rosselli state that the genus is characterized by some unusual traits: spathes fully enclosing the flower-bearing parts of the inflorescences until anthesis, patches of dense indumentums (trichilia) producing Mullerian (food) at the base of the petiole, and anthers becoming detached at anthesis. "Cecropia" is most studied for its ecological role and association with ants . Its classification is controversial; in the past, it has been placed in the Cecropiaceae, Moraceae (the mulberry family), or Urticaceae (the nettle family). The modern Angiosperm Phylogeny Group system places the "cecropiacean" group in the Urticaceae. The genus is native to the American tropics, where it is one of the most recognizable components of the rainforest. The genus is named after Cecrops I, the mythical first king of Athens. Common local names include yarumo or yagrumo, or more specifically "yagrumo hembra" ("female "yagrumo"") to distinguish them from the similar-looking but unrelated "Schefflera" (which are called "yagrumo macho", "male "yagrumo ). In English, these trees are occasionally called pumpwoods (though this may also refer to "C. schreberiana" specifically) or simply "Cecropias". Spanish-speaking countries in Central America, Mexico, the Caribbean, Colombia, and Ecuador commonly use the vernacular name, "guarumo". Classification. The classification can be subjective; many different views exist on how to classify "Cecropia" due to the many changes over the years. The following are two examples, with the second generally more accepted. Classification 1. This version of the classification system is considered the “outdated” version, but is still cited in some sources. Classification 2. This version of the classification system  is considered the newer version and more widely accepted. Taxonomic history. "Cecropia" was first recognized and accounted for by Marcgrave (1648) and Piso (1658), the latter including an illustration with characteristic features. Loefling (1758) coined the generic name "Cecropia". In 1759, Linnaeus described "Cecropia peltata" which he applied to many species. Willdenow (1806) created "C. palmate", which was also applied to a various species. Over the next decade, additional species were added by Bertoloni (1840), Martius (1841), and Liebmann (1851). Mixing of specimens was very common and a problem arose, which continues today, with many collections of "Cecropia". Many species  were also described by Hemsley (1883), Richter (1897), Donnell Smith (1899), Rusby (1907, 1910), Huber (1910), Robinson (1912), Pittier (1917), Bailey (1922), and the most extensive number by Snethlage (1923, 1924). Additional species were recognized by Burret (1924), Mildbread (1925, 1933), Standly (1929, 1940), Macbride (1937), Diels (1941), Standley & Steyermark (1944), and Stadley & Williems (1952). Hans Melchior (1964) placed "Cecropia" in the Urticales and Moraceae (Concephaleideae) because of its woody bark. Later based on the floral characters, most notably the basal ovule and gynoecium, which appears to be formed from a single carpel, Thorne (1976) moved it to the Malvanae-  Urticales, family Urticaceae. Berg (1978), however, placed it in its own family Cercropiaceae. When phylogenetic data became available, "Cecropia" was then moved back into the Urticaceae. Description. The genus is easily identified by its large, circular, palmately lobed leaves, about 30–40 cm in diameter and deeply divided into 7–11 lobes. The trees consist of very few branches, usually with candelabrum-like branching system. In Costa Rica, three-toed sloths are often spotted easily in "Cecropia" trees because of their open, leafless branches compared to other trees. Berg and Roselli state, “Branch development is often initiated in seedlings, even in the  axils of the first formed (opposite) leaves; prophylls are formed, and often the development of the first leaf begins but is arrested (if the seedling is not decapitated). In the axils of the leaves formed during later development, the axillary branch primordia do not produce more than one or two prophylls and a bud.” The branches of "C. garciae" and "C. hispidissima" occur at a height of 0.6 to 1 m and the branches depart at acute angles. In most species of "Cecropia", the branches depart at obtuse angles and the crown has a distinct umbrella shape. High deviation is  seen in the morphology of "Cecropia" species, but most form small to medium-sized trees, 5–15 m tall. Although some species ("C. distachya", "C. herthae", "C. insignis", and "C. sciadophylla") grow much taller, as large as 40 m, and some ("C. ulei") rarely surpass 5 m. The high degree of variation can be attributed to regional habitat differences and longevity. The family Cecropiaceae is characterized by having adventitious roots, and in "Cecropia", they become stilt-roots, which are a common feature of large trees, especially living near rivers or marshes. "Cecropia" spp. are usually full of vines, but not normally  overgrown by them. Most species have internodes that are hollow and contain whitish pith. These internodes provide a nesting area for the "Azteca" ants that inhabit the trees. When the branches are cut, they release a watery, often mucilaginous sap, which turns black when it is exposed to the air. To prevent inhabitation by ants and occupation and damage by herbivorous insect larvae, the terminal buds and upper internodes are filled with mucilage. Several species’ leafy twigs are covered by a waxy layer, making them bluish. Berg and Rosselli describe in detail six types of trichomes that can be recognized  on "Cecropia" and more information on each can be found in their paper. They are: thick unicellular hairs, thin unicellular hairs, pluricellular trichomes, cystolith hairs, pearl glands (or pearl bodies), and Müllerian bodies. Parts of the "Cecropia" such as the stipules, the spathes, and the main veins of the lamina have red-coloring substances. The concentration of the substances varies, even within species, and some parts can be green, bluish, pale pink, dark red, dark purple, and even blackish. The color may fade with age, and can be deposited equally or in patterns such as longitudinal stripes. The leaves of  adult "Cecropia" species are large and peltate, almost circular in circumference. The lamina is attached to the petiole, the venation is radiate, and the lamina is radially incised between the radiating main veins. Variation is high in the number of lobes or leaf segments, ranging from five to more than 20. Similar species. "Pourouma bicolor" is very similar in appearance to the "Cecropia", with its umbrella-shaped leaves, stilt roots, large leaves with wide lobes, and whitish color on the underside. The distinctions between the two, however, are: the petiole attaches at the base of the leaf rather than at  the center of the leaf like "Cecropia" and "Pourouma" has leaf lobes that are triangular and pointed at the tip, whereas most "Cecropia" are rounded. Habitat and distribution. Between 40 and 50% of the 61 species of "Cecropia" are montane or submontane Andean, with the majority of species in the northern part of the Andes, in Colombia and Ecuador. The Andean region is regarded as the center of species richness and speciation because of the additional 25% of lowland taxa that reach the eastern or western foothills of the Andes. Therefore, only about 25% of the species occur outside of  the Andean region. A map of the distribution of "Cecropia" can be found in the article written by Berg and Rosselli, 2005. Most species of "Cecropia" are lowland humid/rainforest species occurring from sea level to 1,300 m in altitude, while submontane species occupy an altitudinal range from 1,300-2,000 m, and montane species are found in cloud forest from 2,000-2,600 m. Many species have a narrow altitudinal and ecological niche, with certain species specializing in specific habitats, such as seasonally inundated habitats, rocky slopes, swamps, natural or man-made clearings, etc. Species in the genus "Cecropia" are some  of the most abundant pioneer tree species in natural tree-fall gaps inside primary forests. Its geographic distribution extends along the Pacific and Atlantic Mexican coasts and in Central and South American forests, and are found over an elevation range of 0 to 2,600 m. "Cecropia" species are among the most abundant pioneers of other neotropical forests. It is native to the Neotropics and occurs as an introduced exotic plant elsewhere. In most low-elevation, wet regions of the Neotropics, "Cecropia" trees are ubiquitous and important invaders of man-made clearings. The species "C. pachystachya" and "C. peltata" are invasive  species in Old World localities including Singapore, Cameroon, Java, Malaysia, Ivory Coast, French Polynesia, and Hawaii. "C. peltata" has been nominated as one of the “100 of the World’s Worst Invasive Alien Species” by the Global Invasive Species Database. "C. peltata" was introduced to the Singapore Botanic Gardens in 1902 and has spread widely throughout Singapore along with "C. pachystachya", which was introduced in the 1960s. The species is successful as an invasive species because of its ability to pollinate without the need for pollinators, the possible preferential liking for its fruits by frugivorous birds, and its lack of  natural predators. Reproduction. "Cecropia" species have staminate and pistillate flowers on separate trees, more commonly referred to as a dioecious species. The fruits are achenes enveloped by a fleshy perianths, oblongoid, elliptic, (sub)obovoid or (sub)ovoid. The pericarp is tuberculate in most species, although it is smooth in some species. Seeds can be viable for more than five years and germinate when triggered by full sunlight and changing temperatures. Full-grown "Cecropia" trees can produce up to a million seeds, and this regular presence of fruits allows this genus to play a major role in the ecosystem. It is often the  keystone food supply for frugivorous animals, such as birds, fruit bats, monkeys, opossums, and even fish. Pollination and dispersal. Traits of the staminate flowers and inflorescences are adapted to wind pollination- either by pendulous spikes, which can be moved by the wind to shed the pollen or by the special adaptation of detachment of anthers, and their secondary attachment allowing the shedding of pollen by motion of anthers. The dryness and its easy release by movement make it ideal for wind pollination. Wind pollination is the dominant form, but insects, small beetles, and flies can be pollinators. In the Neotropics , toucans and other birds help disperse the seeds of species with short infructescences, while bats are associated with species with long peduncles and spikes. Species growing near rivers, though, are usually dispersed by water. Conservation. "Cecropia" spp. are generally not endangered; so no major conservation efforts are in place. Their abundance increases temporarily with the clearing of forest or creation of gaps. Ecology. "Cecropia" species are used as food plants by the larvae of some Lepidoptera species, including the arctiid moth "Hypercompe icasia"; the Cecropia moth ("Hyalophora cecropia") is a North American species, however, thus allopatric with the plant genus . The leaves and buds are also eaten by sloths as their main source of food, but many herbivores avoid these plants; most "Cecropia" spp. are myrmecophytes, housing dolichoderine ants of the genus "Azteca", which vigorously defend their host plants against getting eaten. This symbiosis has been studied extensively by biologists such as Daniel Janzen. "Cecropia" fruit, known as snake fingers, are a popular food of diverse animals, including bats like the common fruit bat ("Artibeus jamaicensis") and "short-tailed fruit bat", the Central American squirrel monkey ("Saimiri oerstedii"), and birds such as the green aracari ("Pteroglossus viridis"), the keel-billed  toucan ("Ramphastos sulfuratus"), the peach-fronted conure ("Eupsittula aurea"), the bare-throated bellbird ("Procnias nudicollis") and particularly nine-primaried oscines. The seeds are not normally digested, so these animals are important in distributing the trees. Some birds – e.g. the common potoo ("Nyctibius griseus") – nest in "Cecropia" trees. The elfin-woods warbler ("Setophaga angelae") is notable for using "Cecropia" leaves as nesting material, which no other New World warbler (family Parulidae) seems to do. Pioneer species. "Cecropia" is a major pioneer tree genus in regions of the Neotropics with wet lowland and montane forest. These trees are characteristic features of many  American tropical rainforest ecosystems and may be among the dominant tree species in some places. Being aggressive, rapid-growth trees, whose succulent fruits are readily sought by various animals, they tend to be among the first pioneer species to occupy former forest areas cleared for pasture or altered by human activity. "C. hololeuca", known in Brazil as "silver cecropia", has broad, silver-hued leaves that make it desirable as an ornamental plant for landscaping projects, as is the case with the similar species "C. pachystachya". Greenhouse experiments have been performed with some species of "Cecropia" indicating them as “gap” and  “pioneer” species under different light regimens and nutrient treatments. Some species ("C. maxima", "C. tacuna", "C. teleabla", and "C. telenitida") do not show the traits of pioneer species, though, as they occur evenly in the forest. The pioneer "Cecropia" species have a higher demand for light, occur in open habitats, relatively rapid growth rates, and short-lived leaves. According to McKey’s theory, these pioneer species tend to invest more heavily in pearl bodies and less heavily in Mullerian bodies than more shade-tolerant species with slower intrinsic growth rates and longer leaf lifespans. In the small light gaps (which  are more shaded than normal), the most distinctive myrmecophytic "Cecropia" spp, are found. Myrmecophytism. Species of "Cecropia" often display myrmecophytism as a form of biotic defense. D.W. Davidson said, Myrmecophytism is a mutualistic relationship formed with ant colonies, where the ants protect the tree from herbivory and the trees provide shelter and food for the ants. Along with protection against herbivory, the ants also prevent the "Cecropia" from encroaching vines and other plants. This may vary between or within species and over geographical locations. The main ants found living in "Cecropia" are different species of "Azteca" ants, although all ants  belong to the same family, the Formicidae. The genus "Azteca" is endemic to the New World and its greatest abundance is in the lowland tropics. In the article written by Davidson, 2005 on page 221, Table 1 contains known obligate Cecropia-ants listed by species and geographic distribution. Ants and "Cecropia" have coadapted to each other, meaning that each species has evolved one or more traits in response to selective pressures exerted by the other. An example is the recognition and use of both prostomata and Mullerian bodies by queens and worker ants. Use. The wood from "Cecropia" trees is  used by local people mainly to make musical instruments and tool handles. Flutes and guitars are commonly made of "Cecropia" wood. In addition, the wood is used for production of matches and cheap boxes. An attempt was made to use the wood to produce paper, but the wood pulp was too high in resin and it was not suitable. The fibers of the bark can be twisted into rope and the ropes are manufactured for bowstrings and hammocks. The leaves can also be burned and the ashes mixed in with roasted and powdered coca leaves to be placed between the  cheek and gum under the tongue as “dip”. The main human use of "Cecropia" trees is planting them in soil erosion-prone areas. The trees make few demands on the soil and grow very quickly. The trees are used in clear-cut areas because they retain the soil, create new biomass, and allow other types of plants to settle in the area. Berg and Rosselli stated that decoctions of leaves are made to stimulate the cardiac system, to treat asthma and pneumonia, to treat diabetes and as a diuretic. Powder of leaves is used for control of Parkinson’s disease  and extract of roots is used to heal wounds or eczema. Red "Cecropia" ("C. glaziovii") shows antidepressant-like activity in rats. Native peoples use "Cecropia" for food, firewood, and in herbalism; some species also have cultural significance. In Trinidad and Tobago, "C. peltata" root is chewed and given to dogs that have been bitten by venomous snakes as an emergency remedy (although there is no strong scientific evidence that this is useful). "Cecropia" leaves can be used as a substitute for sandpaper. In western South America, "Cecropia" leaf ash is used in the traditional preparation of "ypadu", a mild coca -based stimulant. "Cecropia" bark can be used in rope making and in tannery. "Cecropia" wood is used in the manufacture of boxes, toys, aeromodeling models, and rafts. Pharmaceutical applications. So far, no pharmaceuticals in the North or South American markets are based on "Cecropia" species. However, scientists in Brazil have been studying the preparation of pharmaceutical products containing mainly "C. glaziovii" extracts. The preparation of pellets by extrusion-spheronization and polymeric nanoparticles has been reported.