亀の甲せんべい kame no ko senbei: tortoise shell senbei (rice cracker)
Sometimes it is abbreviated to かめせん kamesen.
Kamenoko senbei is shaped like tortoise shell. It is an old-fashioned Okinawa snack, but still popular. It is salty and fried crackers. It is cheap to buy in stores.
There are a few different brands of kamenoko senbei, one is Tamaki snack company. Recently I tried the ume (plum) flavor– it was so good and addictive. It is called 梅小亀 ume kogame (plum small tortoise).
I heard that some people used to eat it with chocolate sauce as a treat for children.
It is easy to find this type of senbei in all the grocery stores.