The Autecology of Eudiaptomus cf drieschi (Poppe & Mrazek 1895 ...

Over 80% of the resting eggs in the upper sediment layers were viable and hatched out
after incubation, but those from the lower layers were less abundant and in poorer
condition. Resting eggs that did not hatch within 14 days of incubation were considered
infertile. Eggs that were damaged or deteriorated did not hatch.
Female E. drieschi produce eggs continuously throughout the entire period they are
found in the water column of the Kinneret. Large clutches (>22 eggs clutch –1 ) of
subitaneous eggs are produced in the early part of the season (Jan-Mar) as the water
begins to warm (15.9-17.0 0 C). By mid-April–May, resting eggs make up about 33.5%
of total eggs produced and clutch sizes range from 8-22. Production of diapausing eggs
increases to about 50% of total eggs from May to June when the water temperature
ranges from 18-23 0 C. Subitaneous and diapausing eggs were never observed together in
the same clutch. The size of the eggs within each clutch is varied. The average size of
subitaneous eggs is 0.142 (+ 0.04) mm (n=300), and diapause eggs 0.153 (+ 0.04) mm
(n= 250).
37
a)