Harvest(wo)man

Leiobunum rotundum

On my way out to the garage the other morning, I spotted this long-legged girl clinging to the bottom of the swallow nest platform, out of the sun. It's a female harvestman (harvestwoman?) belonging to the species Leiobunum rotundum, which has no common name. Though she looks a bit like a spider, with her eight long legs, she's not. Harvestmen (known as daddy-long-legs in the US) are closely related to spiders, but differ in having only a single body segment, rather than the two segments that spiders do. They have just two eyes, rather than the 6-8 that spiders have. You can just see her eyes near the right edge of the smaller (left hand) dark mark on her body; they sit on a tiny turret (called an ocularium). Click on the picture above to enlarge it, if you're having trouble finding them. The dark stripe down the middle of her body is unique, allowing her to be easily identified. The pale patch between her two dark-rimmed eyes is also a useful ID feature. With a body measuring some 7 mm long (1/4-inch) long, she's about twice the size of a male, which would lack the dark body stripe. 

Like all harvestmen, this is an ambush hunter, chasing down small prey including aphids, leafhoppers, flies, moths, spiders and woodlice. Unlike spiders, harvestmen will also feed on carrion and decaying plant matter. This is a common and widespread species right across the UK, though somewhat less so further north. Elsewhere, it widespread across most of Europe, though not around the Mediterranean. It prefers shady, moist habitats. Adults are found from July through November, so we should be seeing them around for a while yet. Ours is the first record for our part of Norfolk in the national database — woohoo!