Caltoris bromus bromus

Leech 1894 - The Extra-spot Swift

A common species on Samui.

It is very similar to a large number of other medium sized brown species, and can only be distinguished with absolute certainty from a set specimen. It usualy, but not always, has an extra small non-hyaline spot in space 1b of the forewing, and may have an extra spot in space 2 of the hindwing.

Flight Period



33 - 38mm

Early Stages

Not known.

Larval Foodplant

Not known.


Assam, throughout Indo-China and the Malay Peninsular,S. China, Borneo, and the Indonesian Islands through to Sulawesi. Another subspecies is found on Taiwan.