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Many snails are found in trees, but only a few are exclusively arboreal for most or all of their life cycle. Tree snails are normally found on the ground only during egg-deposition or when dislodged from their perches. They are frequently large, up to 70 mm long, but tend to be smaller in colder areas. They are restricted to tropical and semi-tropical regions by their need for high humidity and warm temperatures. Tree snails are included in several families, but the Bulimulidae and the Pupillidae are the only two represented on the United States mainland. In the Americas, the center of diversity of the Bulimulidae is in northern South America to Brazil, with representatives spreading northward through Central America and the Caribbean to the southeastern United States (Solem 1969, Breure 1979). The bulimulids are not exclusively arboreal as many species live in leaf-mold, under or near rocks, or on rock faces. However, all native Florida bulimulids are arboreal.

The United States has four native genera of Bulimulidae: Rhabdotus, Drymaeus, Orthalicus, and Liguus. The last three genera are native to Florida. There is also one recently introduced genus in Florida, Bulimulus, which is primarily terrestrial (Thompson 1976). The systematic relationships of the native species were summarized by Pilsbry (1946). The arboreal representatives feed on epiphytic growths such as algae, fungi and lichens on trees.
Figure 1. Orthalicus reses (Say) [left], a federally listed threatened species, and Achatina fulica (Bowditch) [right], a major agricultural pest similar in appearance to Orthalicus reses. Photographs by Division of Plant Industry.

Orthalicus reses (Say) is a federally listed, threatened species due to restricted range and habitat destruction and cannot be legally collected without a federal permit. Liguus fasciatus (Müller) has been proposed as an endangered species in the past but has not been so designated. Most of the other native Florida bulimulids appear to be wide-ranging and numerous. Except for scientific study, these snails should not be collected, as they are not agricultural pests and may actually be beneficial, because they feed on epiphytic growths.

Identification (Back to Top)
The bulimulids of Florida have ovate-conical or bulimoid shells that at maturity range in size from 15 mm to 70 mm. With the exception of Liguus fasciatus, these snails have shells that vary in color from ivory to tan, often with brown markings. Liguus shells are brilliantly colored and are frequently marked with yellow, green, pink, and brown. The bulimulid shell surface is smooth, sometimes glossy, and with protuberances. Live snails are most often found in native hammock trees and shrubs, but frequently live in citrus groves and backyards.

Figure 2. Key identification features. Drawing by Division of Plant Industry.

Key to the Bulimulidae of Florida (Back to Top)
1. Mature shell larger than 40 mm, umbilicus imperforate, apex microscopically smooth . . . . . 5
1'. Mature shell smaller than 40 mm, umbilical perforation narrow, apex microscopically sculptured . . . . . 2

2(1'). Shell thin, translucent to almost transparent, fragile . . . . . 4
2'. Shell solid, opaque to slightly translucent, not fragile . . . . . 3

3(2'). Shell with vertical chestnut brown stripes, blue to black apex . . . . . lined tree snail, Drymaeus multilineatus (Say, 1825). Brown subsutural and basal bands are also present, and can be as wide as 2 mm in some Keys specimens, or lacking altogether. This species is found on terminal twigs of both native and exotic trees and shrubs in the southern counties of Florida, in the Florida Keys, and in the Caribbean.
4'. Shell 15 to 25 mm, with 3 to 5 irregular narrow brown bands on the body whorl, lip of aperture not flared . . . . . Master treesnail, Drymaeus dominicus (Reeve, 1850). The bands can be unevenly broken or even lacking. This species can be differentiated from Drymaeus dormani by the rounder whorls, smaller adult size, and lack of a flared apertural edge. It is found on citrus and native trees in southeastern Florida south of Lake Okeechobee to the Florida Keys and parts of the Caribbean