pterygostome
/ˈtɛrɪɡəˌstəʊm/Zoology
noun
In certain decapod crustaceans: either of a pair of winglike projections of the anterior edge of the ventral carapace, flanking the buccal cavity; this region of the carapace.
Origin
Mid 19th century; earliest use found in James Dana (1813–1895), geologist, zoologist, and teacher. From pterygo- + -stome.