The Terloo Sphinx Moth (Proserpinus terlooi) 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 found from southern Arizona

Arizona

Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

 and Sonora

Sonora

Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....

 in Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

.

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 42-48 mm. The forewing upperside is nearly uniformly greyish-green with a darker green median band. The hindwing upperside has a reddish basal area and a greyish marginal band.

There is one generation per year with adults on wing in July and August. Adults fly during the very late afternoon or evening, nectaring from flowers.

The larvae feed on Boerhavia

Boerhavia

Boerhavia, the spiderlings, is a genus of about 40 species of annual or perennial herbaceous plants in the four o'clock flower family, Nyctaginaceae. The common name refers to the appearance of a spider or spider's web given by the numerous long, slender and interlocking stems of the inflorescences...

species (including Boerhavia coccinea

Boerhavia coccinea

Boerhavia coccinea is a species of flowering plant in the four o'clock family which is known by many common names, including scarlet spiderling, red boerhavia, hogweed, and in Spanish, hierba del cancer and hierba de la hormiga...

and Boerhavia coulteri

Boerhavia coulteri

Boerhavia coulteri is a species of flowering plant in the four o'clock family known by the common name Coulter's spiderling. It is native to the southwestern United States and northern Mexico, particularly the desert areas. This is an annual herb producing an erect or creeping stem up to about 70...

). There are at least three colour morphs, ranging from very pale green to slightly darker green and a mottled brown and gray pattern.