Paralaubuca typus
Paralaubuca typus occurs throughout the survey area, from the Mekong delta to Chiang Saen near the border between the Lao PDR, Thailand and Myanmar. It was reported by all the surveyed stations.
Below the Khone Falls, two distinct and conspicuous migrations occur. From November to February, a non-reproductive upstream migration is undertaken all the way from Kandal, near Phnom Penh, to the Khone Falls (reported by all 13 stations throughout Cambodia).
One Cambodian fisherman from Kompong Cham reported that the
fish came from Tonle Sap as well as from small canals into the
mainstream. Two fishermen from Kandal and Kompong Cham reported
that the migration occurred at about the time of the full moon.
From May to July, the fish migrate downstream (also reported
by all stations). At that time, the fish were reported to be
in reproductive condition. Twenty-two reports confirmed that
mature eggs were observed from May to July. Two fishermen from
Sambor reported observing fish releasing eggs in May. The eggs
were reported to have drifted downstream with the current.
In the Mekong delta, rising water appears to trigger a migration up into canals and then into flooded areas. When the water recedes, the fish return through canals to the mainstream (reported by all three flood-plain stations in Viet Nam).
Spawning was observed by fishermen at two stations in Dong Thap province (Hong Ngu and Tam Nong). At Hong Ngu, spawning was observed in the Mekong mainstream in May, whereas at Tam Nong it was observed in a flood-plain area in June.