Sagmariasus

Lore & Background

Sagmariasus verreauxi was formerly included in the genus Jasus but was separated into its own monotypic genus due to the lack of sculpturation on the abdomen, a feature found in all other Jasus species. The name Sagmariasus derives from the Greek word sagmarion, meaning packhorse, combined with the genus name Jasus, in reference to the common name 'packhorse crayfish'.

The species has numerous common names in English, including Australian crayfish, eastern rock lobster, green crayfish, packhorse lobster, and Sydney crayfish. In Māori, it is called . It lives around northern New Zealand, the Kermadec Islands, the Chatham Islands, and Australia from Queensland to Tasmania.

During the early 20th century, Sagmariasus verreauxi and Jasus edwardsii were among the cheapest seafoods in New Zealand, as European New Zealanders preferred the taste of British crayfish, Austropotamobius pallipes. Large hauls were harvested in Northland, often sold cheaply or used as chickenfeed. The species was occasionally considered a pest that impacted fishing numbers, leading fishermen to sometimes destroy the crayfish. Populations of Sagmariasus verreauxi had declined by the 1970s.

Reader's Guide

Sagmariasus verreauxi holds a distinctive place in both biological and human contexts. Biologically, it is one of the longest decapod crustaceans in the world, alongside the American lobster Homarus americanus, growing to lengths of up to 60 cm. Its separation from the genus Jasus into the monotypic genus Sagmariasus underscores a key morphological difference: the lack of abdominal sculpturation, which is present in all other Jasus species. This taxonomic distinction highlights the evolutionary uniqueness of the species.

In human history, the species was once abundant and cheap in New Zealand, where it was harvested in large quantities in Northland. Despite its size and availability, it was often undervalued, sold cheaply or even used as chickenfeed, because European New Zealanders preferred the taste of British crayfish. The species was even viewed as a pest by some fishermen, who would destroy it. This context illustrates how cultural preferences and economic factors can shape the perception and treatment of a species. By the 1970s, populations had declined, marking a significant shift from its earlier abundance.

Did You Know?

• Sagmariasus verreauxi is probably the longest decapod crustacean in the world, alongside Homarus americanus, growing to 60 cm.
• The genus name Sagmariasus derives from the Greek word for packhorse, referencing the common name 'packhorse crayfish'.
• During the early 20th century, this species was so cheap in New Zealand that it was sometimes used as chickenfeed.
• It was formerly classified in the genus Jasus but was separated due to lacking abdominal sculpturation.