New York Natural Heritage Program
Lance Aplexa
Aplexa elongata (Say, 1821)

Habitat [-]
This snail is a temporary woodland pond specialist (vernal pools) in areas with high calcium concentrations (i.e., over limestone bedrock). Nevertheless, it can sometimes turn up in other temporary wetland habitats that regularly dry up such as marshes, ditches, swales, intermittent streams, and less frequently in permanent water bodies (owing to their transport by water birds). In vernal pools these molluscs play an important role in energy flow because they serve as intermediate hosts for Trematodes (liver and blood flukes) that parasitize amphibians, and in turn they are parasitized by scyomyzid fly larvae. Likewise snails serve as food for a host of invertebrate predators, as well as amphibians and waterfowl, while facilitating nutrient cycling by consuming detritus (Colburn 2004).

Associated Ecological Communities [-]
  • Vernal pool
    An aquatic community of one or more intermittently ponded, small, shallow depressions typically within an upland forest. Vernal pools are typically flooded in spring or after a heavy rainfall, but are usually dry during summer. Substrate is typically dense leaf litter over hydric soils. Vernal pools typically occupy a confined basin (i.e., a standing waterbody without a flowing outlet), but may have an intermittent stream flowing out of it during high water. This community includes a diverse group of invertebrates and amphibians that depend upon temporary pools as breeding habitat. These include amphibians, reptiles, crustaceans, mollusks, annelids, and insects.

Associated Species [-]
  • Spotted Salamander (Ambystoma maculatum)
  • Springtime Fairy Shrimp (Eubranchipus vernalis)
  • Ash Gyro (Gyraulus parvus)
  • Tadpole Physa (Physella gyrina)
  • Thicklip Rams-Horn (Planorbula armigera)
  • Sharp Sprite (Promenetus exacuous)
  • Marsh Pondsnail (Stagnicola elodes)