Notostraca
Guides
Lepidurus
tadpole shrimp
Lepidurus is one of two extant genera of tadpole shrimp (order Notostraca), distinguished from Triops by morphological and ecological traits. Species inhabit temporary freshwater pools, vernal pools, and permanent lakes across diverse climates from Arctic tundra to desert regions. The genus exhibits notable life history flexibility, with resting eggs capable of surviving desiccation and freezing for decades. Some species are of conservation concern due to habitat specificity, while others serve as agricultural pests or bioindicators of environmental change.
Triops
tadpole shrimp, shield shrimp
Triops is a genus of small branchiopod crustaceans in the order Notostraca, commonly known as tadpole shrimp or shield shrimp. The genus is distinguished by having only a pair of long, thin caudal extensions on the telson, unlike the related genus Lepidurus which bears an additional central platelike process. Some species are frequently sold as aquarium pets in dried egg kits, hatching upon contact with fresh water. In agricultural settings, particularly California rice cultivation, certain species function as early-season pests that damage germinating seedlings.