New York Natural Heritage Program
Watercress Snail
Fontigens nickliniana (I. Lea, 1838)
Gastropods

General Description [-]
This is a small snail with a 3.5-4.5 mm long, narrowly conic, shiny black shell with 4.5-7.5 well-rounded whorls and deep sutures where the whorls border one another. The operculum is roundly ovate with 4-5 rapidly enlarging spirlas and is about 1.0 mm in width.

Identifying Characteristics [-]
This is a moderate to large-sized species (within Fontigens) with an elongate conic shell. It is most similar to Fontigens aldrichi, but this species does not occur in New York.

Characters Most Useful for Identification [-]
The elongate conic shell is distinctive.

Best Life Stage for Proper Identification [-]
Adult

Behavior [-]
This species may become introduced into new sites with Watercress. Snails of this family typically lay eggs singly on hard substrates, including the shells of other Gastropods (Johnson et al., 2013). Lifespan is in the range of 2-5 years.

Diet [-]
This snail gleans diatoms from the surface of Watercress (Nasturtium officinale) plants.
Watercress Snail Images
click to enlarge
The Best Time to See
Activity levels are unknown, but older museum specimens from Erie County were collected in February. Populations typically maintain high densities year-round, suggesting continuous reproduction (Dillon et al., 2006).
J F M A M J J A S O N D
Present Active
The time of year you would expect to find Watercress Snail present (blue shading) and active (orange shading) in New York.