Theretra insignis 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 Sphingidae

Sphingidae

Sphingidae is a family of moths , commonly known as hawk moths, sphinx moths and hornworms, that includes about 1,200 species . It is best represented in the tropics but there are species in every region . They are moderate to large in size and are distinguished among moths for their rapid,...

 family. It is known from Indonesia

Indonesia

Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

.

It is very similar to Theretra kuehni

Theretra kuehni

Theretra kuehni is a moth of the Sphingidae family. It is known from Indonesia.It is very similar to Theretra insignis but smaller and the forewings are less pointed. The forewing upperside is as in Theretra insignis, but the silvery-white band between the third and fifth postmedian lines is more...

but larger and the forewings are more pointed. The upperside of the abdomen has two strong white dorsal lines, sometimes partly fused. The forewing upperside is similar to Theretra turneri

Theretra turneri

Theretra turneri is a moth of the Sphingidae family. It is known from Queensland.The wingspan is about 60 mm. Adults have light brown forewings with a number of dark brown markings. They have plain brown hindwings....

but the space between the third and fifth postmedian lines is silvery-white and curved and the sixth postmedian line is only slightly dentate.