Harvestmen are so named because most species become more conspicuous in late summer and early autumn. Photograph: Alamy

I was grubbing up dandelions and bindweed in the brassica cage when I felt something brush against my hand. The creature’s oversized legs and loping gait gave it an alien appearance, reminding me of the towering Martian fighting-machines in HG Wells’s The War of the Worlds. It was a harvestman, so named because most species mature and become more conspicuous in late summer and early autumn.

At first glance harvestmen are easily mistaken for spiders, but aside from having eight legs and belonging to the class arachnid, they have little in common with true spiders. They don’t produce silk, so are unable to spin webs and they lack venom glands. Their appearance is also very different from that of a spider, as the cephalothorax is fused with the abdomen, giving their bodies the appearance of a coffee bean.

This individual was beautifully marked with a dark-brown saddle, bordered by a broad, indented white line. Where a spider generally has six or eight eyes set at the front of its cephalothorax, the harvestman had two beady black eyes perched on a little turret. Its legs splayed out on either side of its body like inexpertly applied false eyelashes. As it strode across my palm, I noticed that it used its first, third and fourth pairs of legs to walk, while its elongated second set of legs tapped my skin as it felt and scented the unfamiliar terrain beneath its feet.

As the harvestman headed towards the damp, dark cover of a rosette of kale, it passed a sunbathing wolf spider. In the manner of its namesake, the spider began to stalk the unsuspecting harvestman, keeping out of sight behind protruding flints. Sensing danger, the harvestman picked up its pace, using its stilt-like legs to effortlessly scale the mountainous clods of earth in its path. Just as it appeared to be losing ground, the spider surged forward and lunged at the harvestman, pinning it to the ground, but the harvestman shed a leg and slipped from its grasp. As the amputee bolted for cover, the spider struck repeatedly at the still-twitching limb.

Twitter: @ClaireStares