Thirty two new species of Lytopylus (Agathidinae) are described with image plates for each species: Lytopylus
alejandromasisi
sp. n., Lytopylus
alfredomainieri
sp. n., Lytopylus
anamariamongeae
sp. n., Lytopylus
angelagonzalezae
sp. n., Lytopylus
cesarmorai
sp. n., Lytopylus
eddysanchezi
sp. n., Lytopylus
eliethcantillanoae
sp. n., Lytopylus
ericchapmani
sp. n., Lytopylus
gahyunae
sp. n., Lytopylus
gisukae
sp. n., Lytopylus
guillermopereirai
sp. n., Lytopylus
gustavoindunii
sp. n., Lytopylus
hartmanguidoi
sp. n., Lytopylus
hernanbravoi
sp. n., Lytopylus
hokwoni
sp. n., Lytopylus
ivanniasandovalae
sp. n., Lytopylus
johanvalerioi
sp. n., Lytopylus
josecortesi
sp. n., Lytopylus
luisgaritai
sp. n., Lytopylus
mariamartachavarriae
sp. n., Lytopylus
miguelviquezi
sp. n., Lytopylus
motohasegawai
sp. n., Lytopylus
okchunae
sp. n., Lytopylus
pablocobbi
sp. n., Lytopylus
robertofernandezi
sp. n., Lytopylus
rogerblancoi
sp. n., Lytopylus
salvadorlopezi
sp. n., Lytopylus
sangyeoni
sp. n., Lytopylus
sarahmeierottoae
sp. n., Lytopylus
sergiobermudezi
sp. n., Lytopylus
sigifredomarini
sp. n., and Lytopylus
youngcheae
sp. n. A dichotomous key and a link to an electronic, interactive key are included. All specimens were reared from Lepidoptera larvae collected in Area de Conservación Guanacaste (ACG) and all are associated with ecological information including host caterpillar, collection date, eclosion date, caterpillar food plant, and locality. Neighbor-joining and maximum likelihood analyses of the barcode region of the mitochondrial cytochrome c oxidase subunit I gene (COI DNA barcode) were conducted to aid in species delimitation.