[Cephalopoda] The sharp, spike-like extension on the posterior tip of the gladius or cuttlebone.

[Crustacea] Generally, the anterior projecting median extension of carapace between eyes or ocular peduncles; it may be straight or curved, armed with teeth or unarmed.
In Ostracoda, the beak-like anterior projection of the valve margin, above and in front of the incisure; found mainly in the Myodocopida.