This part has not been updated since 2012. Alot of new species have been found in the meantime, especially by Oleg Kosterin. Under references you find the way to his articles.
Damselflies recorded in Cambodia
Calopterygidae
Neurobasis chinensis
Vestalis gracilis
Chlorocyphidae
Libellago hyalina 
Libellago lineata
Heliocypha
biforata 
Heliocypha perforata
Aristocypha
fenestrella 
Aristocypha
fulgipennis 
Euphaeidae
Dysphaea gloriosa
Euphaea guerini
Euphaea masoni
Lestidae
Lestes concinnus 
Lestes elatus
Lestes platystylus
Lestes
praemorsus 
Orolestes octomaculata
Megapodagrionidae
Coenagrionidae
Aciagrion borneense
Aciagrion hisopa
Aciagrion occidentale
Aciagrion pallidum
Aciagrion
tillyardi
Aciagrion spec.
Agriocnemis
femina
Agriocnemis lacteola
Agriocnemis minima
Agriocnemis
nana 
Agriocnemis pygmaea
Archibasis oscillans
Archibasis
viola
Argiocnemis rubescens
Ceriagrion
auranticum 
Ceriagrion
calamineum
Ceriagrion cerinorubellum
Ceriagrion
indochinense 
Ceriagrion
malaisei 
Ceriagrion olivaceum
Ceriagrion praetermissum
Ceriagrion
spec. red 
Ischnura aurora
Ischnura.
senegalensis 
Mortonagrion
aborense
Mortonagrion falcatum
Onychargia atrocyana
Paracercion
calamorum dyeri 
Pseudagrion
australasiae 
Pseudagrion
microcephalum
Pseudagrion pruinosum
Pseudagrion rubriceps
Pseudagrion williamsoni
Platycnemididae
Coeliccia kazukoae
Coeliccia ocotgesima?
Coeliccia
yamasakii
Coeliccia spec.,
Coeliccia rolandorum
Copera ciliata
Copera
marginipes 
Copera vittata
Protoneuridae
Prodasineura
autumnalis 
Prodasineura
verticalis sensu 