A whole host of jumping spiders spend their days crawling up and down tree trunks. The ones that live many meters above the ground are hard to get, but the ones that get down to eye level are pretty easy to find.

Often you can find the tree-trunk dwellers just by looking, but because many are colored just like tree bark, it helps to tap the trunk with a stick to provoke them to move and show themselves. When none is seen, or if you are impatient, there's another method: brushing the trunk with a brush, while a beating sheet is held underneath to catch those dislodged. Here's Edy in action:

Brushing a tree trunk.

Brushing a tree trunk.

I think you can see that beating sheets are used for more than just beating (see my post on "Beating around the bushes"). They also serve as umbrellas and picnic blankets.

Brushing a tree trunk yesterday, Edy found the most surprising spider of the trip, an adult female that's tiny -- about 1.6 mm long. She has a narrow body and strangely placed eyes (the spider, that is). We didn't even know what subfamily she belonged to, so we called her "Gray Pixie". Today, we found males. Males are easier to identify because their palpi, which they use to transfer sperm, often have traits characteristic for a large group of species, even if their bodies have evolved to take on diverse forms. The palpi indicate that these are probably a very strange species of Laufeia, which normally have much larger bodies:

"Gray Pixie" jumping spider

"Gray Pixie" jumping spider

Previously in this series:

Spiders in Borneo: Introduction

Spiders in Borneo: Undiscovered biodiversity

Spiders in Borneo: The guests of honor: Salticidae

Spiders in Borneo: Team Salticid

Spiders in Borneo: Mulu National Park

Spiders in Borneo: Dreaming about salticid spiders

Spiders in Borneo: Jumping spiders in the forest

Spiders in Borneo: Beating around the bushes

Spiders in Borneo: Spiders in leaf litter

Text and images © W. Maddison, under a Creative Commons Attribution 3.0 license (CC-BY)