Species Account – Flower Crab Spider (Misumena vatia)

On the 30th May we officially dated our first garden record for the stunning Flower Crab Spider, although in truth we have seen it before now on several occasions. This impressive predator is always something worth looking out for, it’s one of those species you cannot quite believe is native to these shores and great to have in Brislington.

Until this year, when we spotted this species we always noted it in the colour form shown below, as taken in July near the wildlife pond. A sort of white’ish green with pink patches.

We were aware and had seen photographs online about it appearing from time to time in a yellow form, often very bright yellow and in May this year we finally witnessed this for ourselves, this time lurking menacingly in the apple tree. Apparently this species can change it’s colour within the range of the above to the below to best suite it’s surroundings. Although we were a little baffled as pale green/white would have made this little lady stand out less on the pale underside of the leaf we found her on. But maybe invertebrates view these colours differently, or perhaps she had moved up from the creeping buttercups at the base of the tree. In any case we did read that in order to turn full on yellow like this, the female (males don’t have this ability) has to accumulate a certain substance within her skin which can take up to three weeks, so it must be a gradual change.

It’s fairly clear to see why it’s called a crab spider looking at those vicious front legs and it really does move side to side like a crab when it wants to. She wont spin a web to catch her prey, rather she sits and waits, relying on her camouflage to conceal her. It seemed incredible to us that hunting like this would allow her to capture prey as large as a bumble bee until we witnessed it ourselves (see video below).

One thing that we found amazing is how quickly the bee succumbed to the spiders venom, by the time we started recording it was really all over for the poor bee, it had ceased to struggle. The spider would have injected her enzymes and the process of dissolving her meal from the inside had probably already begun.

Next summer we will be on the look out for the much smaller male of the species.

DC 30/11/2021