Tadpole shrimp

Systematic position: The tadpole shrimp (Triops) belongs to the order Notostraca, family Triopsidae. These crustaceans are often called living fossils due to their ancient morphological structure, which has remained largely unchanged for millions of years of evolution.

Crops damaged: Rice is the primary crop impacted by this organism. Tadpole shrimp thrive in standing, warm, shallow water, making flooded paddy fields an ideal habitat for their mass development during the early stages of rice cultivation.

Biology and life cycle: The lifecycle of Triops is highly adapted to ephemeral environments. Their eggs are capable of remaining dormant in dry soil for years. Upon irrigation, they hatch rapidly, reaching sexual maturity within a few weeks and producing thousands of eggs, which ensures a persistent presence in the soil seed bank.

Nature of damage and harmfulness: As benthic foragers, tadpole shrimp constantly disturb the bottom sediment. This movement dislodges newly sprouted rice seeds and delicate roots, causing significant stand reduction. Additionally, the increased turbidity caused by their digging blocks sunlight, negatively affecting the initial growth and photosynthetic capacity of the rice seedlings.

Control measures: Effective management requires a combination of strategies to minimize crop losses:

• Precision land leveling to ensure uniform water depth and prevent deep pooling.
• Timely irrigation and drainage management to disrupt the lifecycle of the larvae.
• Application of targeted insecticides in accordance with regional agricultural safety regulations.
• Integration of biological controls, such as introducing fish species that feed on tadpole shrimp larvae in paddy environments.