Notostraca Temporal range:
| |
---|---|
Triops australiensis | |
Lepidurus apus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Branchiopoda |
Superorder: | Calmanostraca |
Order: | Notostraca G. O. Sars, 1867 |
Genera | |
The order Notostraca, containing the single family Triopsidae, is a group of crustaceans known as tadpole shrimp[1] or shield shrimp.[2] The two genera, Triops and Lepidurus, are considered living fossils, with similar forms having existed since the end of the Devonian, around 360 million years ago. They have a broad, flat carapace, which conceals the head and bears a single pair of compound eyes. The abdomen is long, appears to be segmented and bears numerous pairs of flattened legs. The telson is flanked by a pair of long, thin caudal rami. Phenotypic plasticity within taxa makes species-level identification difficult, and is further compounded by variation in the mode of reproduction. Notostracans are omnivores living on the bottom of temporary pools and shallow lakes.
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