Stenopodidea
Boxer shrimps are a distinct decapod group, not true shrimp or prawns.
The boxer shrimps, or Stenopodidea, form a small group within the decapod crustaceans. Though frequently mistaken for Caridea shrimp or Dendrobranchiata prawns, they are neither, constituting their own distinct group.
In terms of anatomy, Stenopodidea lack the branching gills found in Dendrobranchiata prawns. They also brood their eggs rather than releasing them directly into the water. They differ from Caridea shrimp in having a greatly enlarged third pair of legs.
Taxonomically, Stenopodidea belongs to the order Decapoda and is most closely related to the Caridea and Procarididea infraorders. A 2019 cladogram by Wolfe and colleagues illustrates these relationships within Decapoda. Currently, 71 living species are recognized, divided among 12 genera. Three fossil species are also known, each placed in its own genus. The earliest fossil assigned to the group is *Devonostenopus pennsylvaniensis* from the Devonian period; before its discovery, the oldest known member was *Jilinicaris chinensis* from the Late Cretaceous.
The internal relationships of Stenopodidea are shown in a cladogram, with the group comprising the following families and genera: †Dubiostenopus, Macromaxillocarididae (with *Macromaxillocaris*), Spongicolidae (including *Engystenopus*, *Globospongicola*, †*Jilinicaris*, *Microprosthema*, *Paraspongicola*, *Spongicola*, *Spongicoloides*, *Spongiocaris*), and Stenopodidae (including †*Devonostenopus*, *Juxtastenopus*, *Odontozona*, †*Phoenice*, *Richardina*, *Stenopus*).
Quick Facts
- Taxon
- Stenopodidea
Facts from the source article.
Lore & Background
Stenopodidea can be differentiated from Dendrobranchiata prawns by their lack of branching gills and by brooding their eggs instead of releasing them directly into the water. They differ from Caridea shrimp by their greatly enlarged third pair of legs. The group belongs to the order Decapoda and is most closely related to the Caridea and Procarididea infraorders, as shown in a cladogram from analysis by Wolfe et al., 2019.
Reader's Guide
The Stenopodidea are notable for being a small but distinct lineage within Decapoda, often misidentified as true shrimp or prawns. Their anatomy—particularly the lack of branching gills, egg brooding, and enlarged third legs—sets them apart. The group includes 71 extant species across 12 genera, with three fossil species each in separate genera. The earliest known fossil, Devonostenopus pennsylvaniensis from the Devonian, pushed back the group's known history; before its discovery, the oldest member was Jilinicaris chinensis from the Late Cretaceous. The internal taxonomy comprises families such as Macromaxillocarididae, Spongicolidae, and Stenopodidae, with genera ranging from extant forms like Stenopus to extinct ones like Dubiostenopus. Their evolutionary relationships, clarified by Wolfe et al., 2019, place them as a sister group to Caridea and Procarididea, underscoring their unique position among decapods.
Did You Know?
- Stenopodidea are often confused with Caridea shrimp or Dendrobranchiata prawns but belong to their own group.
- They lack branching gills and brood their eggs, unlike Dendrobranchiata prawns.
- Their third pair of legs is greatly enlarged, distinguishing them from Caridea shrimp.
- The earliest fossil assigned to Stenopodidea is Devonostenopus pennsylvaniensis from the Devonian.
More in Marine Shrimp, Part 2 1-24
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced