Mystery Snails





 




Rob Caron has written an article for the Lake Stewards of Maine regarding SPIA's efforts to control the invasive snails. You can read that article here.
Generally found in flowing water or proximity to flowing water (e.g., river mouths). Adults >25mm. Live-bearers - juvenile snails are retained inside the mantle of the mother for several weeks. Feed primarily on particulate detritus in soft sediments.
 
Campeloma decisum

Shell aperture oval - operculum with a concentric (central) nucleus. Outer shell surface greenish in color with no banding, shell interior white to light blue. Shoulders of whorls rounded and distinct from previous whorl - sutures that separate whorls are indented. Smooth with no sculpturing other than fine striae. 25mm.
   
Viviparus georgianus

The shell aperture and operculum nearly circular - operculum with a concentric (central) nucleus. Outer shell surface brown to tan with 4 bands. Shell interior usually white or with a purplish hue. Shoulders between shell whorls weak, sutures are indented. 38mm.
   
Cipangopaludina chinensis and japonica

Shell aperature round to oval with a reflected, black pigmented lip. Operculum with a submarginal (located nearer the outer lip) nucleus. Outer shell surface light to dark olive-green, without any color bands. Whorls are strongly convex, with a very slight shoulder, and the suture is deeply indented. Shell sculpture consists of fine growth lines, spiral lines and fine to moderate malleations over the entire surface.

C. chinensis - shell with more rounded shoulders and broader shape

C. japonica - narrower and more turreted shell - sculpted (carinate). to 65mm.
   
 
Profile - University of Michigan Animal diversity web
 

 




Rob Caron has written an article for the Lake Stewards of Maine regarding SPIA's efforts to control the invasive snails. You can read that article here.
 
Generally found in flowing water or proximity to flowing water (e.g., river mouths). Adults >25mm. Live-bearers - juvenile snails are retained inside the mantle of the mother for several weeks. Feed primarily on particulate detritus in soft sediments.
 
Campeloma decisum

Shell aperture oval - operculum with a concentric (central) nucleus. Outer shell surface greenish in color with no banding, shell interior white to light blue. Shoulders of whorls rounded and distinct from previous whorl - sutures that separate whorls are indented. Smooth with no sculpturing other than fine striae. 25mm.
   
Viviparus georgianus

The shell aperture and operculum nearly circular - operculum with a concentric (central) nucleus. Outer shell surface brown to tan with 4 bands. Shell interior usually white or with a purplish hue. Shoulders between shell whorls weak, sutures are indented. 38mm.
   
Cipangopaludina chinensis and japonica

Shell aperature round to oval with a reflected, black pigmented lip. Operculum with a submarginal (located nearer the outer lip) nucleus. Outer shell surface light to dark olive-green, without any color bands. Whorls are strongly convex, with a very slight shoulder, and the suture is deeply indented. Shell sculpture consists of fine growth lines, spiral lines and fine to moderate malleations over the entire surface.

C. chinensis - shell with more rounded shoulders and broader shape

C. japonica - narrower and more turreted shell - sculpted (carinate). to 65mm.
   
 
Profile - University of Michigan Animal diversity web