It also has a prominent tubercle (small nodule) on shoulder of the carapace.

The claws of Pontastacus leptodactylus are long and narrow (hence the common name 'narrow-clawed crayfish').

A study done by R. Salighehzadeh saw that after collecting 10 narrow-clawed crayfish found that they contained 2 pathogenic isolates simultaneously, the Aeromonas hydrophilia and Fusarium solani.

[8] Pontastacus leptodactylus is fairly docile, especially the male with large claws, and favours relatively still fresh and brackish waters such as lakes, lagoons and canals, as well as running waters in rivers.

[1] Media related to Astacus leptodactylus at Wikimedia Commons