This list is based on the database of HK AFCD. There are 125 listed as of Aug. 13, 2018. However, there was a taxanomic swamp, replacing Aciagrion tyillyardi with Aciagrion approximans.

Aciagrion tillyardi 蒂氏狹翅蟌
https://www.afcd.gov.hk/tc_chi/conservation/hkbiodiversity/database/popup_record.asp?id=2001&lang=tc

, which is considered a synonym in World Odonata List v197

Source : World Odonata List
https://www.pugetsound.edu/academics/academic-resources/slater-museum/biodiversity-resources/dragonflies/world-odonata-list2/

Aciagrion approximans
Schemes : IUCN Red List of Threatened Species. Version 2012.1, IUCN Red List of Threatened Species. Version 2012.2, IUCN Red List of Threatened Species. Version 2014.3, GBIF, World Odonata List