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 (no͞o′mə-stōm′, nyo͞o′-)
A small opening in the mantle of a pulmonate gastropod through which air passes.

[From New Latin pneumostoma : pneumo- + Greek stoma, mouth.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
The dissection was conducted by inserting fine point scissors, from the mantle edge, at the pneumostome level, initially cutting near the anus and then along the rectum, exposing the pallial cavity roof, folded to the left.
operant conditioning of aerial respiration results in snails attempting to open their respiratory orifice, the pneumostome, significantly less often (Lukowiak et al., 1996).
This caused the snails to open up their pneumostome (breathing tube) to get oxygen from the air.
When the snail opened its pneumostome at the surface, it was given a gentle poke with a wooden stick, causing it to close again.
Tactile stimulation of the lips, tentacles, mantle edge, and pneumostome effectively produces geotactic responses.
The edge of the mantle skirt is divided into left and right lobes, either side of the pneumostome. These encircle the base of the neck in the active animal.