Branchiopod
Guides
Artemiidae
Brine Shrimp
Artemiidae is a family of branchiopod crustaceans containing the single genus Artemia, commonly known as brine shrimp. These organisms inhabit hypersaline inland waters worldwide where their extreme salinity tolerance excludes most predators. The family has remained morphologically unchanged since the Triassic period. Artemiidae species serve as important food sources for waterbirds and as intermediate hosts for avian cestodes. Their desiccation-resistant cysts have enabled commercial harvest and widespread use in aquaculture as live feed.
Chirocephalidae
fairy shrimp
Chirocephalidae is the second largest family of fairy shrimp (Anostraca), characterized by a reduced or vestigial maxilla, more than two setae on the fifth endite, divided pre-epipodites, and widely separated seminal vesicles. The family includes nine genera: Artemiopsis, Branchinectella, Chirocephalus, Dexteria (extinct), Eubranchipus, Linderiella, Parartemiopsis, Polyartemia, and Polyartemiella. Former families Linderiellidae and Polyartemiidae are now included within Chirocephalidae. Most species are distributed in the Holarctic region.
Eubranchipus
fairy shrimp, vernalis fairy shrimp, eastern fairy shrimp
Eubranchipus is a genus of freshwater fairy shrimp (Anostraca: Chirocephalidae) comprising 21 described species. These small branchiopods inhabit temporary pools and vernal ponds across North America, Europe, and Asia. Populations exhibit rapid life cycles synchronized with ephemeral aquatic habitats, hatching from desiccation-resistant resting eggs when pools fill and completing development before summer desiccation.
Eubranchipus vernalis
springtime fairy shrimp, eastern fairy shrimp
Eubranchipus vernalis, commonly called the springtime fairy shrimp or eastern fairy shrimp, is a small freshwater crustacean in the family Chirocephalidae. It inhabits seasonal pools and vernal wetlands across North America. The species is named for its spring emergence pattern, appearing in temporary waters following winter thaw. As a branchiopod, it represents an ancient lineage of aquatic arthropods with specialized filtering appendages.
Eulimnadia
clam shrimp
Eulimnadia is a genus of small freshwater branchiopods commonly known as clam shrimp. The genus is notable for its rare androdioecious mating system, where populations consist of males and hermaphrodites but lack pure females. This reproductive strategy has persisted for an estimated 24–180 million years across multiple speciation events, making it one of the most stable examples of androdioecy known in animals. Species are distinguished primarily by the morphology of their resting eggs (cysts), which show distinctive sculpturing patterns. The genus contains approximately 13–25 described species with a cosmopolitan distribution across every continent except Antarctica.
Haplopoda
Haplopoda is an infraorder of branchiopod crustaceans within the order Diplostraca. It contains the single extant family Leptodoridae, represented by the genus Leptodora, commonly known as the water flea Leptodora kindtii. This group is notable for being among the largest predatory cladocerans. The infraorder is now treated as a synonym of Onychopoda in many modern classifications.
Lynceidae
clam shrimp
Lynceidae is a family of small, bivalved crustaceans commonly known as clam shrimp, classified in the order Laevicaudata. The family contains approximately 5 genera and more than 20 described species, with the genus Lynceus being the most species-rich and well-studied. Members are distinguished from other clam shrimp families by specific morphological features of the carapace, head, and male clasping appendages. Lynceidae species inhabit temporary aquatic habitats across multiple continents, though many species have restricted distributions due to habitat destruction.
Lynceus
clam shrimp
Lynceus is a genus of clam shrimp in the family Lynceidae, comprising approximately 13 described species. These small branchiopod crustaceans inhabit temporary aquatic habitats, including desert rockholes, gnammas, and dolines. The genus has been subject to recent taxonomic revision, particularly in Australia where six species are now recognized. Species identification relies on morphological characters including male first thoracopod structure, head and rostrum form, antenna 2 spinal patterns, carapace shape, and the female lamina abdominalis.
Onychopoda
Onychopoda is a specialized order of predatory branchiopod crustaceans within the superorder Cladocera, distinguished by having only four pairs of legs (compared to five or six in related orders) and segmented raptorial appendages used for grasping prey. The order comprises three families (Cercopagididae, Podonidae, Polyphemidae), ten genera, and approximately 33 described species. Most species are endemic to the Ponto-Caspian basin, though some occur in freshwater and marine habitats worldwide. Onychopoda exhibits one of the most distinctive morphological and ecological radiations among cladocerans, having evolved predation as a novel feeding strategy and colonized habitats across a broad salinity range.
Spinicaudata
clam shrimp
Spinicaudata is an infraorder of small, bivalved branchiopod crustaceans commonly known as clam shrimp. They inhabit temporary freshwater pools, saline lakes, and rock holes (gnammas) across arid and semi-arid regions worldwide. The group is characterized by a laterally compressed body enclosed within a hinged, clam-like carapace. Many species produce drought-resistant resting eggs that persist in dry sediments until favorable conditions return. Reproductive modes vary, with some lineages exhibiting androdioecy (hermaphrodites with occasional males) and others gonochorism (separate sexes with ~1:1 ratios).
Streptocephalus
Rams-horn Fairy Shrimps
Streptocephalus is a genus of fairy shrimp (Anostraca) found in temporary freshwater habitats across Africa, Australia, Eurasia, and the Americas. Its distribution reflects an ancient Gondwanan origin. The genus is characterized by distinctive mandibular morphology adapted for processing diverse food sources. Species in this genus are obligate inhabitants of ephemeral aquatic environments, with life cycles synchronized to the temporary nature of their habitats.