About 25, see text Cecropia is a Neotropical genus consisting of 61 recognized species with a highly distinctive lineage of dioecious trees.

Spanish-speaking countries in Central America, Mexico, the Caribbean, Colombia, Ecuador commonly use the vernacular name, guarumo.

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).

[2] Additional species were recognized by Burret (1924), Mildbread (1925, 1933), Standly (1929, 1940), Macbride (1937), Diels (1941), Standley & Steyermark (1944), and Stadley & Williems (1952).

[4] 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.

[2] 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.[2] The high degree of variation can be attributed to regional habitat differences and longevity.

[2] 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.

[2] To prevent inhabitation by ants and occupation and damage by herbivorous insect larvae, the terminal buds and upper internodes are filled with mucilage.

[2] 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.

[2] 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.

In most low-elevation, wet regions of the Neotropics, Cecropia trees are ubiquitous and important invaders of man-made clearings.

[2] 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.

The leaves and buds are also eaten by sloths as their main source of food,[9] 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.

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)[10] and particularly nine-primaried oscines.

Cecropia is a major pioneer tree genus in regions of the Neotropics with wet lowland and montane forest.

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.

[9] 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.

[2] The pioneer Cecropia species have a higher demand for light, occur in open habitats, relatively rapid growth rates, and short-lived leaves.

In the article written by Davidson, 2005 [2] 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.

[2] The wood from Cecropia trees is used by local people mainly to make musical instruments and tool handles.

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).

[9] In western South America, Cecropia leaf ash is used in the traditional preparation of ypadu, a mild coca-based stimulant.