Look at this soft, fluffy bundle of newness. This little man is the Lavasoa dwarf lemur (Cheirogaleus lavasoensis), a newly described species of dwarf lemur from southern Madagascar.
The first Lavasoa dwarf lemur was picked up during an expedition in the Lavasoa Mountains region of Madagascar in 2001, but ever since it's been wrongly assigned to another dwarf lemur species. Now, a team led by Andreas Hapke from the Institute of Anthropology at Germany's Johannes Gutenberg University Mainz has published a genetic analysis of several species of dwarf lemur to confirm that there are six, not five, known species. Their analysis compared data from 40 dwarf lemur samples collected in 2005 with samples from 11 individuals caught in recent field expeditions. Hapke's team caught the notoriously difficult to find dwarf lemurs by enticing them with bananas, then photographing, measuring and gently extracting tiny tissue samples before releasing them back home that night.
The Lavasoa dwarf lemur weighs no more than 300 g and stretches to around 54 cm, its tail contributing to half its total length. It has a pointed muzzle, big black rings around its eyes, and dark, rounded ears that perch neatly in a reddish golden coat. This fox-like colouring runs over its head and down its torso, gradually fading to grey. Its undersides are also grey, and look very soft and are practically begging for scritches. You can tell it likes scritches.
Hapke and his colleagues, Dana Thiele, also from the Johannes Gutenberg University, and Emilienne Razafimahatratra from the University of Antananarivo in Madagascar, report that the new species is restricted to three isolated forest fragments in the Lavasoa Mountains, which sit in the middle of where the island's vegetation transitions from dry, spiny bush to thick, humid forest. They've estimated that less than 50 of these little primates remain in the wild.
So now we have six species of dwarf lemur - a genus larger than the mouse lemur but smaller than the gentle lemur. What makes them and the mouse lemurs so difficult to find is that they spend most of their time high up in the forest canopy, plus they're nocturnal, plus they're most active during the rainy season, which just happens to make their forests inaccessible to researchers. They're also the only known primates to hibernate, so they'll be hidden for up to seven months per year.
Dwarf lemur hibernation was first reported in the Lavasoa dwarf lemur's closest relative, the fat-tailed dwarf lemur (C. medius) from western Madagascar. In 1999, researchers from the University of Hohenheim in Germany described in Oecologia how over a period of two or three weeks every year, these primates would fatten themselves up on a diet of 80% sugary fruits and nectars while avoiding any calorie-burning activity. Sometimes they'd end up doubling their entire body mass in this short period, which helped them to hibernate their way through the cold and lean Madagascan dry season that runs from the end of April to October.
Just like chipmunks, the fat-tailed dwarf lemur hibernates in the holes of trees, but two other species of dwarf lemur prefer to hibernate in the ground. Earlier this year, a team led by biological anthropologist Marina Blanco from Duke University in North Carolina reported in Scientific Reports that the newly rediscovered Sibree’s dwarf lemur (C. sibreei) and Crossley’s dwarf lemur (C. crossleyi) from the high-altitude forests of central and eastern Madagascar dig into the soft humus and leaf litter on the forest floor to create a shallow burrow. Here they'll hibernate for three to six months during the dry season underneath a warm layer of soil.
It's not yet known whether the Lavasoa dwarf lemur hibernates, but judging from the behaviour of its relatives, it's a pretty good bet that it does.
And here's a video of baby fat-tailed dwarf lemur triplets managing to look both sleepy and super-wired all at once: