New animals are found all the time. Most are insects. When mammals are discovered, we humans sit up and notice. News is reaching the cryptozoology world of the confirmation of another new mammal, a giant flying squirrel.

In September 2012, a team from the National University of Laos surveyed markets in central Lao PDR for squirrels. In one of the many small markets, Master’s student Daosavanh Sanamxay found something remarkable, a single specimen of a flying squirrel previously undescribed to science. The researchers described this newly discovered species in a 2013 Zootaxa publication, giving it the English name: the Laotian giant flying squirrel (Biswamoyopterus laoensis).

The Laotian giant flying squirrel is only the second record of the genus, Biswamoyopterus, the first being the Critically Endangered Namdapha flying squirrel (Biswamoyopterus biswasi), known only from a single physical example collected in 1981 in Arunachal Pradesh, India. The new Laotian giant flying squirrel is also the first record of the genus from Southeast Asia. Source.

The July 15, 2013 scientific paper in Zootaxa 3686 (4): 471–481,  notes the details, specifically:

Abstract

A new species of the flying squirrel genus Biswamoyopterus is described from Lao PDR. It is based on a single specimen collected from a local food market at Ban Thongnami, Pak Kading District, Bolikhamxai Province. The new taxon shows close affinities to Biswamoyopterus biswasi, which is only known from the holotype collected in 1981, 1250 km from the current locality, in Arunachal Pradesh, Northeast India. However, it differs substantially in pelage colour, most particularly on the ventral surfaces of the body, patagia, tail membrane, and tail. The single specimen was found in an area of central Lao PDR, which is characterised by its extensive limestone karst formations and which is home to other rare endemic rodents, including the Kha-nyou (Laonastes aenigmamus) and the Lao limestone rat (Saxatilomys paulinae).

Introduction

In March–May, 1981, Dr. Shyamrup Biswas of the Zoological Survey India collected a unique flying squirrel from a proposed biosphere reserve in Namdapha, Tirap District, Arunachal Pradesh, India. It was subsequently described as a new genus and species, Biswamoyopterus biswasi Saha (1981), the Namdapha flying squirrel.

Information about this taxon was summarised in a series of publications including Corbet and Hill (1992), Thorington and Hoffmann (2005), Thorington et al. (2012), and the species was listed as Critically Endangered in the IUCN Red List (Molur 2008). However, until now, the genus was only known from the holotype specimen (Reg. No. 20705) which resides in the Zoological Collection of the Zoological Survey of India, Kolkata [Calcutta], India.

In September 2012, a team from the National University of Laos undertook a survey of flying squirrels in the informal food markets of northern, central and southern Lao PDR. In the market at Ban (village) Thongnami, Pak Kading District, Bolikhamxai Province, central Lao PDR (Fig. 1), they observed several species of Pteromyini including Hylopetes phayrei Blyth, Petaurista elegans Müller, and P. philippensis Elliot for sale as ‘bush-meat’. In addition, there was a female specimen of a large flying squirrel, which superficially resembled P. philippensis but differed in a number of external characters. On subsequent examination in the university museum, this individual was also found to have cranial and dental characters that clearly differentiated it not just from P. philippensis but from the genus Petaurista itself.

A review of the literature confirmed that it was referable to the elusive genus Biswamoyopterus but that it differed specifically from B. biswasi. Therefore, it is described here as a new species to science, the second record of the genus, and the first record of the genus from Lao PDR and Southeast Asia.