Spinicaudata

Spinicaudata is an infraorder of crustaceans belonging to the subclass Branchiopoda, commonly known as tadpole shrimp or fairy shrimp. These small, aquatic arthropods are characterized by their elongated, segmented bodies and a pair of large, leaf-like appendages called phyllopods, which they use for swimming and respiration. Their name, Spinicaudata, refers to the spiny tail-like furca found at the posterior end of their bodies, though this feature is not always prominent.

These crustaceans are found in temporary freshwater habitats worldwide, including vernal pools, ephemeral ponds, and desert oases. Their life cycle is well-adapted to these environments. They typically lay drought-resistant eggs, called cysts, which can remain dormant for extended periods, sometimes years, until favorable conditions of water and temperature return. Upon hatching, the larvae undergo several molts to reach adulthood.

Spinicaudata are important components of freshwater ecosystems. They are detritivores, feeding on decaying organic matter, and also consume algae and bacteria. In turn, they serve as a food source for various aquatic animals, including insects, fish, and birds. Their presence can be an indicator of healthy, temporary aquatic environments. While many species are small and inconspicuous, their ecological role is significant.