Neohelice

Lore & Background

The first report of Neohelice likely came from Alcide d'Orbigny during an expedition to South America between 1826 and 1834. He described the crab's ecology and burrows but did not name the species. The first taxonomic description was made by James Dwight Dana in 1851, who named it Chasmagnathus granulatus following the United States Exploring Expedition. In 1918, Mary J. Rathbun redescribed the species under the name Chasmagnathus granulata, which was used alongside Dana's original name for many years.

In 2006, Katushi Sakai, Michael Türkay and Si-Liang Yang revised the genera Helice and Chasmagnathus, restricting both to East Asian species. They erected the new genus Neohelice for the South American species, which became Neohelice granulata. Two other genera, Austrohelice and Pseudohelice, were also created in the same revision. The species inhabits salt marshes and estuaries, feeding on sediment, Spartina, and plant-derived detritus.

Reader's Guide

Neohelice granulata has emerged since the 1980s as a model species in a variety of biological fields. Much of the scientific research has focused on its tolerance of both fresh water and brine (euryhalinity) and its semiterrestrial habit. It has also been investigated for research into neurophysiology, neurobiology of learning and memory, toxicology, and ecosystem dynamics. Such breadth of study is unusual for a model organism.

In 2009, Eduardo Spivak tallied the number of scientific papers published about different crab species over the previous 23 years. Neohelice granulata was found to be the sixth most studied crab species, after Carcinus maenas, Callinectes sapidus, Scylla serrata, Cancer pagurus, and Metacarcinus magister, but ahead of the invasive Chinese mitten crab (Eriocheir sinensis) and the commercially important snow crab (Chionoecetes opilio). This ranking underscores the species' importance as a research subject despite not being a major fishery or invasive pest.

Did You Know?

• Neohelice granulata is the only species in the genus Neohelice.
• The genus was erected in 2006 by Sakai, Türkay, and Yang.
• In 2009, it was estimated to be the sixth most studied crab species.
• Its diet in the wild consists mostly of sediment, Spartina, and plant-derived detritus.