Hi from Algeria

In case I have any regular readers, I thought I should explain that I'm currently enjoying a holiday in Algeria and nearly incommunicado as far as the Internet is concerned. The local dialectological situation - a conservative qaf-dialect of Arabic in Dellys itself, a "Bedouin-type" gaf-dialect in the villages immediately around it, and Kabyle beyond it to the east and south - is quite historically suggestive, and I'm still looking into its origins; however, to be honest, I'm spending rather more time on the beach, which brings me to a question: does anyone have any idea what the etymology of "luggi", the local Arabic word for sea urchin, might be? Or even know of another area where this term is used? My guess would be Berber, but I haven't found a convincing answer yet. Many local seafood names seem to be found in Corriente's Dictionary of Andalusi Arabic (often with Vulgar Latin etymologies), but not this one.