The Australopacific Saprininae, containing twelve genera and forty species, are reviewed, illustrated and keyed to genera and species. Two new genera, Australopachylopus
gen. n. (New Zealand, type species Saprinus
lepidulus Broun, 1881) and Iridoprinus
gen. n. (Australia, type species I.
myrmecophilus
sp. n.) and four new species: Saprinus (Saprinus) rarus
sp. n. (Australia), Saprinus (Saprinus) chathamensis
sp. n. (Chatham Islands, New Zealand), Saprinus (Saprinus) pseudodetritus
sp. n. (Chatham Islands, New Zealand) and Saprinus (Saprinus) pacificus
sp. n. (Kiribati) are described. The Saprininae fauna of the Australopacific Region is a mixture of northern invaders that most likely arrived to the region in early Cenozoic by ‘island hopping’ from north (Hypocaccus, Hypocacculus, several Saprinus) and truly autochthonous taxa either with uncertain phylogenetic affinities (Iridoprinus
gen. n., Saprinodes Lewis, 1891, Reichardtia Wenzel, 1944, Australopachylopus
gen. n.), primitive Australopacific endemics (e.g. Tomogenius Marseul, 1862) or presumed relicts (several species of Saprinus Erichson, 1834). Several Saprininae taxa (Chalcionellus
aeneovirens (Schmidt, 1890); (Gnathoncus
rotundatus (Kugelann, 1792); G.
communis (Marseul, 1862); Euspilotus (Neosaprinus) rubriculus (Marseul, 1855); Hypocaccus (Nessus) interpunctatus
interpunctatus (Schmidt, 1885); Saprinus (S.) chalcites (Illiger, 1807) and Saprinus (S.) cupreus Erichson, 1834)) were introduced into the region with human activity. We report the first cases of myrmecophily (Iridoprinus
myrmecophilus
gen. et sp. n.) and termitophily (Saprinus
rarus
sp. n.) in the Saprininae from the Australopacific Region. Lectotypes and paralectotypes of the following taxa are designated herein: Saprinus
amethystinus Lewis, 1900, Saprinus
apricarius Erichson, 1834, Saprinus
artensis Marseul, 1862, Saprinus
auricollis Marseul, 1855, Saprinus
australasiae Blackburn, 1903, Saprinus
bistrigifrons Marseul, 1855, Saprinus
certus Lewis, 1888, Saprinus
communis Marseul, 1862, Saprinus
cupreus Erichson, 1834, Saprinus
cyanellus Marseul, 1855, Hister
cyaneus Fabricius, 1775, Saprinus
dentipes Marseul, 1855, Saprinus
desbordesi Auzat, 1916, Saprinus
gayndahensis MacLeay, 1871, Saprinus
hyla Marseul, 1864, Saprinus
incisisternus Marseul, 1862, Saprinus
incisus Erichson, 1842, Saprinus
irinus Marseul, 1862, Saprinus
laetus Erichson, 1834, Saprinus
lepidulus Broun, 1881, Saprinus
mastersii MacLeay, 1871, Saprinus
nitiduloides Fairmaire, 1883, Saprinus
pedator Sharp, 1876, Saprinus
pseudocyaneus White, 1846, Saprinus
rubriculus Marseul, 1855, Saprinus
sinae Marseul, 1862, Saprinus
tasmanicus Marseul, 1855, Saprinus
tyrrhenus Blackburn, 1903, Saprinus
varians Schmidt, 1890, Saprinus
vernulus Blackburn, 1903, Saprinus
viridanus Lewis, 1899, Saprinus
viridipennis Lewis, 1901, and Saprinus
westraliensis Blackburn, 1903. The synonymy of Saprinus
tyrrhenus Blackburn, 1903 is revoked and the species is considered as valid (stat. n.). Seven new synonymies are proposed: Saprinus
gayndahensis MacLea...