UPDATING THE SOUTHEAST-ASIAN NEPTOSTERNUS SHARP FAUNA-II (COLEOPTERA,DYTISCIDAE)

One new species of rheobiotic Dytiscidae, Neptosternus chumphon is des cribed from Thailand. Neptosternus togatus Guignot. 1954 [described fr om Indonesia, Java] is suggested to be a junior subjective synonym of N. corporaali Zimmermann, 1924, which is now reported from Java for th e first time. The median lobe of N. taiwanensis Hendrich sr Balks, 199 7 is depicted for the first time and new distributional reports for N. hydaticoides (Regimbart, 1877) [Taiwan, West Malaysia] and N. jacobso ni Zimmermann, 1927 [Java] are provided. A total of 54 Neptosternus sp ecies are now known from SE Asia.