The Brown-throated Sunbird is a relatively large (14 cm), heavy sunbird with a thick bill.
The male has a brown face, pinkish-brown throat and a blue-green crown and back. 
The female is olive-green above and yellowish below and can be distinguished from other sunbirds by her robust size and the broken pale yellow eyerings (clearly visible on the first two photos). 
It is found in a wide range of semi-open habitats in south-east Asia.

Ben Tre area, Mekong Delta, Vietnam, 22 & 23 December 2023