One I missed, back when it appeared in spring 2019. Swamp Monsters is a 144-page survey of swamp monsters in American comics, from the days before the Comics Code. With a 15-page introduction and survey.

Related is a forthcoming December 2019 book on what grew out of such schlock… Monstrous Imaginaries: the legacy of Romanticism in the comics. This will look at… “Enki Bilal’s Monstre tetralogy, Jim O’Barr’s The Crow, and Emil Ferris’s My Favorite Thing Is Monsters … Alan Moore’s Swamp Thing“.