Freshwater mussels have evolved multiple strategies to infect fish hosts with their larvae (glochidia). Here are some examples from different mussel species. (A) Epioblasma triquetra: physical entrapment of the host. (B) Ptychobranchus subtentum: releasing conglutinates containing glochidia that mimic invertebrate prey items. (C) Hamiota perovalis: ‘‘fishing behavior” using a tethered superconglutinate containing glochidia. (D) Lampsilis cardium: displaying mantle lure. (E) Anodonta implicata: broadcasting individual glochidia. (F) Pyganodon grandis: releasing a mucous web of glochidia. (A)–(D) represent ‘‘lure” strategies that induce a predatory response in the fish host, and E and F represent ‘‘non-lure” broadcast strategies.

Figure used with permission from: Hewitt, T.L., C.L Wood and D. O. Foighil. 2019. Ecological correlates and phylogenetic signal of host use in North American unionid mussels. International Journal for Parasitology 49:71-81.