Palaemonidae

Lore & Background

The family Palaemonidae was formerly split into two subfamilies, but molecular and morphological research in 2015 determined that those subfamily groupings were invalid. At the same time, the members of the families Gnathophyllidae and Hymenoceridae were incorporated into the Palaemonidae. Many species are carnivores that eat small invertebrates, though others generally feed on detritus. Some species inhabit coral reefs, where they associate with certain invertebrates as cleaner shrimps, parasites, or commensals. The genus Macrobrachium is significant for containing commercially fished species. The former family Gnathophyllidae, now placed within Palaemonidae, consisted of about 14 species in five genera: Gnathophylleptum, Gnathophylloides, Gnathophyllum, Levicaris, and Pycnocaris. These shrimp were often associated with echinoderms.

Reader's Guide

Palaemonidae is a large and ecologically significant family of shrimp, with more than 1200 species across 160 genera. Its members occupy virtually all aquatic habitats except the deep sea, from freshwater to coral reefs. The family includes the commercially important genus Macrobrachium, which is fished for human consumption. Many Palaemonidae species play key roles in coral reef ecosystems, forming associations with sponges, cnidarians, mollusks, and echinoderms as cleaner shrimps, parasites, or commensals. Their feeding habits vary: some are carnivores that hunt tiny animals, while others feed on detritus. The family's classification was revised in 2015, when molecular and morphological research invalidated the former two-subfamily division and incorporated the families Gnathophyllidae and Hymenoceridae into Palaemonidae. The former Gnathophyllidae, consisting of about 14 species in five genera, were often associated with echinoderms. This taxonomic revision reflects ongoing scientific understanding of shrimp relationships.

Did You Know?

• The genus Macrobrachium contains commercially fished species.
• In 2015, molecular and morphological research invalidated the former two-subfamily groupings and incorporated Gnathophyllidae and Hymenoceridae into Palaemonidae.