Biomphalaria glabrata is an intermediate snail host for the trematode Schistosoma mansoni, which is one of the main schistosomes that infect humans.

[2] There is a great deal of information available about this snail, because it has been, and continues to be, under intensive study by many malacologists, parasitologists and other researchers, on account of its medical significance.

[1] Say's type description reads as follows: Shell sinistral; whorls about five, glabrous or obsoletely rugose, polished, destitute of any appearance of carina; spire perfectly regular, a little concave; umbilicus large, regularly and deeply concave, exhibiting all the volutions to the summit; aperture declining, remarkably oblique with respect to the transverse diameter.

[33] Biomphalaria glabrata snails lay egg masses at rather a high rate (about 1 per day).

[34] The weight of the embryonic shell in 5-day-old (120-hours-old) embryos a very short time before hatching, is 30.3 μg, and the width is 500 μm.

[27][35][36] The typically unilateral copulations[37] are initiated when a male actor mounts the shell of a prospective mate.

Following a typically 5–87 min penis intromission with usually successful sperm transfer,[38] the male actor retracts to terminate copulation.

[27] Biomphalaria glabrata is a major intermediate host for Schistosoma mansoni in the Americas and a vector of schistosomiasis.

[39] In medical research, the most commonly used Biomphalaria glabrata snail stock (used for the maintenance of Schistosoma mansoni) is albino, i.e. it is without pigment.

[40] Not only did this albino variety prove to be highly susceptible to Schistosoma mansoni, but the lack of pigment allowed investigators using a dissecting microscope to view the development of the parasite within the snail.

Li et al 2021 finds resistant snails to have innate immune receptors specifically to fight S. mansoni infection.

[13] Interactions between snails and schistosomes are complex and there exists an urgent need to elucidate pathways involved in snail-parasite relationships as well as to identify those factors involved in the intricate balance between the snail internal defence system and trematode infectivity mechanisms that determine the success or failure of an infection.

[2] Molluscs appear to lack an adaptive immune system like that found in vertebrates and, instead, are considered to use various innate mechanisms involving cell-mediated and humoral reactions (non-cellular factors in plasma/serum or hemolymph) that interact to recognize and eliminate invading pathogens or parasites in incompatible or resistant snails.

However, a diverse family of fibrinogen-related proteins (FREPs)[50] containing immunoglobulin-like domains has been discovered in Biomphalaria glabrata and may play a role in snail defence.

Circulating haemocytes (macrophage-like defence cells) in the snail haemolymph are known to aggregate in response to trauma, phagocytose small particles (bacteria, and fungi) and encapsulate larger ones, such as parasites.

Final killing is effected by hemocyte-mediated cytotoxicity mechanisms involving non-oxidative and oxidative pathways, including lysosomal enzymes and reactive oxygen/nitrogen intermediates.

Certain alleles of cytosolic copper/zinc superoxide dismutase (SOD1) have been associated with resistance also suggesting these processes are important in the snail internal defence system.

This suggests FREPs are detecting these mucins and recognition or failure to recognize helps to determine the course of the infection interaction.

[51][52] Melanoides tuberculata is considered to be a competitor of Biomphalaria glabrata, but all the intraspecific interactions are not fully understood yet.