Harvestman

So are they referring to the same thing or different species?

Here's an example of how "daddy long-legs" doesn't really apply. This is a harvestman in the Order Opiliones, just like the one in the spotting above. It is a short-legged variety. Doesn't seem much like a "long-legs," does it? ;-)

http://www.projectnoah.org/spottings/110...

There are many - often in Europe - that refer to spiders in the family Pholcidae as "daddy long-legs." Some folks in the U.S. also use the term for those spiders. They are also known as cellar spiders. Here's another reason why scientific names are so important... ;-)

Ah, that is the problem with common names both "harvestman" and "daddy long-legs" are used to refer to the order Opiliones. It is not a matter of confusion but difference in common name usage, I was an adult before I ever heard a species of Opiliones referred to as "harvestman".

I recently posted a spotting of one of these in Iowa City.. It's actually a Harvestman, often confused with daddy long legs. They are arachnids but NOT spiders, and they only have two eyes, rather than eight!