The species of Agraphydrus RÉGIMBART, 1903 from Australia, Brunei, Indonesia, Laos, Malaysia, Myanmar, Papua New Guinea, Thailand, and Vietnam are revised. Agraphydrus biprojectus MINOSHIMA, KOMAREK & ÔHARA, 2015, A. coronarius MINOSHIMA, KOMAREK & ÔHARA, 2015, A. geminus (ORCHYMONT, 1932), A. jaechi (HANSEN, 1999), A. malayanus (HEBAUER, 2000), A. orientalis (ORCHYMONT, 1932), A. regularis (HANSEN, 1999), A. siamensis (HANSEN, 1999), and A. thaiensis MINOSHIMA, KOMAREK & ÔHARA, 2015 are redescribed. Sixty new species are described: A. anacaenoides, A. angulatus, A. bacchusi, A. balkeorum, A. borneensis, A. brevipenis, A. burmensis, A. carinatulus, A. cervus, A. clarus, A. delineatus, A. engkari, A. excisus, A. exiguus, A. floresinus, A. hamatus, A. helicopter, A. hendrichi, A. heterochromatus, A. hortensis, A. imitans, A. infuscatus, A. jankodadai, A. kathapa, A. laocaiensis, A. latus, A. lunaris, A. maehongsonensis, A. manfredjaechi, A. mazzoldii, A. microphthalmus, A. mirabilis, A. muluensis, A. musculus, A. namthaensis, A. nemo- rosus, A. nigroflavus, A. obesus, A. orbicularis, A. pallidus, A. papuanus, A. penangensis, A. piceus, A. raucus, A. reticulatus, A. rhomboideus, A. sarawakensis, A. schoedli, A. scintillans, A. shaverdoae, A. skalei, A. spadix, A. spinosus, A. stramineus, A. sucineus, A. sundaicus, A. tamdao, A. tristis, A. tu- lipa, A. vietnamensis. Agraphydrus superans (HEBAUER, 2000) is synonymized with A. jaechi.
The genus Agraphydrus is recorded from Brunei for the first time. Agraphydrus activus KOMAREK & HEBAUER, 2018 is recorded from Thailand for the first time, A. coomani (ORCHYMONT, 1927) is recorded from Brunei, Indonesia, Laos, Myanmar, and Thailand for the first time, A. arduus KOMAREK & HEBAUER, 2018, A. biprojectus MINOSHIMA, KOMAREK & ÔHARA, 2015, A. confusus KOMAREK & HEBAUER, 2018 from Laos, A. masatakai MINOSHIMA, KOMAREK & ÔHARA, 2015 from Myanmar and Vietnam. Agraphydrus anhuianus (HEBAUER, 2000) and A. malayanus were erro- neously recorded from Thailand by MINOSHIMA, KOMAREK & ÔHARA (2015), resp. by HEBAUER (2000). Agraphydrus anhuianus is so far confirmed only for China (Anhui), and therefore it is here excluded from the fauna of Southeast Asia.
A total of eighty described species is now known from Southeast Asia and the Australian Region. Agraphydrus coomani is widespread in the Oriental and Australian regions, while most of the other species are restricted to one or two countries. Thirty-one species were collected in Malaysia, 17 in Thailand as well as in Indonesia, 16 in Vietnam, and only one species is known from Australia. Eleven of the species were collected also in China, A. connexus and A. coomani also on the Indian Subcontinent.
The habitat of six species is unknown, all other species were collected in aquatic habitats. Fifteen species were collected at light, at least some species were found in hygropetric habitats.
Habitus, male genitalia and other morphological details are illustrated, distribution maps are pre- sented, and a key to the species is added.