This survey aims to provide an updated species checklist of aquatic and semi-aquatic bugs in the intra-Philippine biogeographic region of Mindoro. An assessment survey of water bugs (Hemiptera, Heteroptera) was conducted by mostly manual collection in selected areas of Oriental Mindoro from 2017 to 2018, in which some of the collecting activities were contributed by graduate students of Ateneo de Manila University.

Twenty-nine aquatic and semi-aquatic heteropteran species were documented and some are known island-endemic species or subspecies, including Enithares martini mindoroensis Nieser & Zettel, 1999, Hydrotrephes stereoides mindoroensis Zettel, 2003, Aphelocheirus freitagi Zettel & Pangantihon, 2010, Rhagovelia mindoroensis Zettel, 1994, Rhagovelia raddai Zettel, 1994, Rhagovelia potamophila Zettel, 1996, and Strongylovelia mindoroensis Lansbury & Zettel, 1997, which were found in new areas in the region. In addition, there are also new records for the island that have already been documented before in other parts of the Philippines, such as the Philippine-endemic Ochterus magnus Gapud & San Valentin, 1977 and Hebrus philippinus Zettel, 2006, and the widely distributed backswimmers Anisops nigrolineatus Lundblad, 1933 and Anisops rhomboides Nieser & Chen, 1999. Several undescribed specimens and potentially new species are also discussed in this paper. Further surveys in the other parts of Mindoro, and in the other regions of the Philippines, are encouraged to produce a comprehensive baseline data of heteropteran species richness in the country.