The role of temperature in egg development of three aquatic insects Lestagella penicillata (Ephemeroptera), Aphanicercella scutata (Plecoptera), Chimarra ambulans (Trichoptera) from South Africa

- Sub-lethal effects of water temperature on egg development were assessed in three aquatic insect taxa at six temperature treatments ranging from 5-30 °C.
- 90% hatching success was recorded for Lestagella penicillata eggs in the 10, 15 and 20 °C treatments respectively, while greater variability in hatching success (between 5-20%) was recorded for Chimarra ambulans at a wider range of temperatures (10-25 °C).
- In contrast 80% of Aphanicercella scutata eggs hatched at 10 and 15 °C compared to only 30% success at 20 °C Thermal reaction norms revealed L. penicillata and C. ambulans to be warm adapted, but A. scutata to be cold adapted.
- Data are valuable for species conservation and setting guidelines for e- flow studies.