Oviposition and Post-Embryonic Development of the Watermite Piona Alpicola (Neuman, 1880)

Some aspects of the biology of the watermite Piona alpicola were studied. The food was composed of Cladocera and chironomid larvae. The eggs were laid in oblong rows, that usually contained 5 to 20 eggs. While laying the eggs the female moves backwards. The process of egg laying is described. Hibernating females under laboratory conditions, began to lay eggs in March and April. The period of egg laying can last for more than a month. The maximum number of eggs counted per female was approximately 340. Laboratory-bred females began laying 14, 18 or 20 days after copulation. The larvae appeared to parasitize upon the imagines of Chironomus plumosus and C. tentans. The larvae attach themselves to the intersegmentalia of the abdomen of the chironomid. The length of the various developmental phases was determined. We concluded that two, possibly even three generations appear per year.