Bellulia postea is a moth

Moth

A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

 of the Micronoctuidae

Micronoctuidae

The Micronoctuidae are a family of moths that includes about 400 described species. The family was first described in 2005.Micronoctua karsholti is the smallest of all species in the Noctuoidea superfamily.-Taxonomic History:...

 family. It is known from northern Vietnam

Vietnam

Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

.

The wingspan

Wingspan

The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...

is about 13 mm. The forewing is light brown. The crosslines are all present and blackish. The antemedial, upper half of subterminal line and terminal line are well
marked. The hindwing is greyish brown, with a discal spot and the underside is unicolorous grey.