Synalpheus regalis

Synalpheus regalis
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Caridea
Family: Alpheidae
Genus: Synalpheus
Species:
S. regalis
Binomial name
Synalpheus regalis
Duffy, 1996 
Synonyms

Zuzalpheus regalis (Duffy, 1996)

External image
Images and further information from 'ants', Thailand

Synalpheus regalis is a species of snapping shrimp that commonly live in sponges in the coral reefs along the tropical West Atlantic. They form a prominent component of the diverse marine cryptofauna of the region. For the span of their entire lives, they live in the internal canals of the host sponge, using it as a food resource and shelter. It has been shown that colonies contain over 300 individuals, but only one reproductive female. Also, larger colony members, most of which apparently never breed, defend the colony against heterospecific intruders. This evidence points towards the first known case of eusociality in a marine animal.

The species name "regalis" comes from the Latin regalis which means royal. This likely stems from the structural hierarchy of the colonies in which only a single female produces all of the offspring.