(To reduce the spider-density in Nature’s Nether Regions, I had to sacrifice this paragraph in the final version of the book’s manuscript. But, thanks to the blog, it is not lost:)
Behold the tiny Mysmena spiders from the Gaoligongshan mountains in the Yunnan province of China. The less-than-a-millimetre-long spiders live a hidden life among leaf litter and rocks, where they build tiny tangle-webs. One way arachnologists manage to track down these near-invisible spiders is by dusting the forest floor with puffs of cornstarch; the starch particles get stuck in the sticky spider web threads, which makes them stand out and point the way to the hiding place of the animal that made it. My colleague Jeremy Miller and his spider friends used this technique to discover six new species, all of which were nondescript, similar-looking, brownish micro-spiders. As usual, most diversity was in the male and female genitals. The pedipalp (spiders use these stubby arm-like structures near their heads to transfer their sperm) of some species had wavy riblets, others had very long, coiled, whip-like extensions, while yet other species had a deep groove across it. And ditto on the female side of the sexual divide: the ‘lid’ that covers their vulva (a barrier the sperm-loaded pedipalp needs to breach) is simple in some species, while in others it has an elephant-trunk-like protrusion on it, which goes straight up in one species, and curves backward in another.
The paper in which Jeremy Miller and colleagues describe the new Mysmena spiders (as well as 30 other new micro-orbweaver spider species) from Gaoligongshan is :
Miller, J.A., C.E. Griswold & C.-M. Yin, 2009. The symphytognathoid spiders of the Gaoligongshan, Yunnan, China (Araneae: Araneoidea): systematics and diversity of micro-orbweavers. Zookeys, 11: 9-195.