A SQUID BEAK

Squid beaks (mandibles) are interesting, yet most people have never even seen one of these structures.

Squid beaks are a two-part structure consisting of chitin, a tough material and, in fact, one of nature’s toughest materials. These beaks are even harder than some metals! A squid uses its beaks in order to dismember their prey. Squid beaks are similar looking to those found in an octopus.

Squid beaks work like scissors and also have a super hard tip. The beaks are like a bird’s beak: very sharp and surrounded by fleshy material that absorbs force without fracturing. Squid (and similar looking octopus) beaks are among the hardest organic materials known!

Squid beaks are mainly indigestible, making them somewhat common finds in the stomachs of predators (especially whales) that eat squids. 

The geologically oldest known impressions of squid bodies are from the middle late Cretaceous (about 85 mya) (Wikipedia, 2025).

But, the oldest known squid beaks are late Jurassic age. There are also Cretaceous) and Cenozoic fossilized cephalopod beaks (usually referred to as rhyncholites = calcified cephalopod beaks). 

Rhyncholites are  known from England, Belgium, Italy, Romania, Egypt, Cuba, Central America, as well as from Mississippi, and southern California. The southern California rhyncholites are from the San Diego area, in the Ardath Shale of middle Eocene age (Teichert and Stanley, 1975).

Figure 1. A complete modern-squid beak consisting of two, interlocking parts: 3.75 mm height, 2.4 mm wide. The parts consist of chitin, an organic material secreted by the squid. The locale of where this beak was collected is not known.