Feeding Pholcidae


Sep 4, 2010
A couple months ago, I noticed a small spider building a web between the legs of a wooden stool. I moved the stool to a safer place (ie, one where my cats wouldn't notice it as easily) and began to observe it regularly.

It seems like a member of the Pholcidae family - it has long, slender legs, a small, two-segment body, and often exhibits the characteristic behavior of "vibrating" its web whenever prey comes into it. So far it's been very content to lazily hang upsidedown in its web all day, quite eagerly springing upon any live ants I drop into the web.

I'm not sure about the exact type it might be, though; I haven't found a picture that looks just right, though it bears a fair amount of relation to pictures of Holocnemus pluchei. It's sort of a pale brown with a dark streak down the underside of its body, and I would describe its abdomen as slightly globular rather than the 'rectangle' a lot of websites describe various types of pholcidae as. I live in California, if that helps give an idea as to what sort it might be.

As I mentioned before it's quite happy to dine on whatever ants I find trying to get into the house or out in the back yard (typically I feed it 4-5 or so a week, one a day, sometimes more sometimes less), but I'm concerned maybe it needs a broader diet than that to meet its nutritional needs. I'm not certain what they normally eat, or what would be good to feed them, or if I should be feeding it more ants daily; I have no idea if they can possibly overeat and if that'd be dangerous for their health.

It's definitely gotten bigger since I found it, though! (I've never seen it leave its web to hunt, so I assume the ants I'm feeding it are most of what it's eating, but I don't know.)

Any information would be great, thanks!

John Apple

Just a guy
Old Timer
Jan 26, 2003
Really neet spiders....the long legged lurkers of many a basement and crevace across the country
keep it how you are....they feed on anything wrapping the prey item to an almost unrecognisable white thing....
Ants and flies are usually the norm as well as isopods [seen all this in webs and below them]
The vibrating thing is s defence mechanism....makes the spider blurry and hard to see...birds, rodents and the wayward human:)
be careful as they will shed a leg when grabbed or even molested....

Bill S

Old Timer
Oct 2, 2006
We have Pholcids in our house - Physocyclus sp. If one starts looking especially thin we'll toss it a small cricket, moth or whatever else is convenient. Pholcids also eat other spiders. A diverse diet is no doubt better for them than getting only one type of prey, so offering more than ants is a good idea.