Close-up views:

I have originally named this fern as Pteris speciosa which is native to South America (Colombia, Ecuador, Panama and Peru). A few years later, I saw another similar looking fern (Pteris biaurita) while browsing the Internet. After further investigation, the vein pattern of the fronds (leaves) seem to indicate that the fern should be Pteris biaurita. This fern is native to Thailand, Laos and Cambodia. By chance, its spores came with the soil that I obtain from the nursery and it started to germinate in my pot.