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Tadpole Shrimp cont. characteristics of tadpole shrimp include a shield-like carapace (shell), a fused pair of eyes on top of the carapace, a segmented abdomen, and paired tail filaments. Tadpole shrimp also have paired ventral appendages called phyllopods (phyllo = "leaf" and pod = "feet"), which beat in a wavelike motion from front to back and act as propulsion for the animal. At the base of these paired phyllopods is a ventral midline food groove, which effectively funnels microscopic food particles up to the animal’s mouth. This basic design appears to be well-adapted to the vernal pool environment, since these basic body characteristics have remained unchanged over time. Tadpole shrimp belong to either the genus Triops or the genus Lepidurus. The tadpole shrimp in the genus Lepidurus have a paddle-shaped flap between the tail filaments, which shrimp in the genus Triops do not. Lepidurus packardi is the only species in the genus Lepidurus known from California’s Central Valley or the San Francisco Bay Area. A ventral view of a vernal pool tadpole shrimp, note the paired pyllopods, paired ventral antennae, segmented abdomen, and orange egg sac. Vernal Pool Habitat and Vernal Pool Tadpole Shrimp Life Cycle Vernal pools are ephemeral (short-lived) wetlands that form in areas where a Mediterranean climate combines with shallow depressions underlain by soil types that restrict the downward percolation of water. A Mediterranean climate is a moderate climate with distinct and regular wet and dry seasonality. In California, the soils which form the water-restricting layer associated with |
Last updated:
May 27, 2008
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