Not sure if it's spelled correctly, but it's pronounced "wa-cha-PO-teh".
Nasty little boogers these. Looks like something out of an old Star Trek episode. These things are no joke when they get trapped inside your sandal! The folks here call them espinas once they're inside your skin. Each tine has a little barb on the end which makes it rather velcro-ish and very difficult to remove!
Just another lovely part of life in the desert!