glochidium

noun

glo·​chid·​i·​um glō-ˈki-dē-əm 

plural glochidia glō-ˈki-dē-ə 

: the larva of a freshwater mussel (family Unionidae) that develops as an external parasite on fish

Word History

Etymology

borrowed from New Latin, from Greek glōchid-, glōchī́s "projecting point (as the end of a yoke fastening or the barb of an arrow)" + New Latin -idium -idium; so named from the hook-like appendages with which the larvae attach themselves to fish — more at gloss entry 3

Note: Term introduced by the Norwegian zoologist Jens Rathke (1769-1855) in "Om Dam-Muslingen," Skrivter af Naturhistorie-Selskabet [Copenhagen], 4. Bind, 1. Hefte (1797), p. 166. As a vernacular equivalent of glochidium Rathke gives Krogskjæl, "hook shell."

First Known Use

1875, in the meaning defined above