Fig. 10 in The ecological role of immature phantom midges (Diptera: Chaoboridae) in the Eocene Lake Messel, Germany

Fig. 10. Vertical diurnal migration of the last larval instar of Chaoborus punctipennis in the extant meromictic Crawford Lake, Canada. Crawford Lake is continuously anoxic below 14 m, but the anaerobic boundary may vary seasonally from 11 to 14 m. The hours are plotted horizontally, the depth in metres is plotted vertically. Horizontal scale shows number of individuals/m3. Modified after Sardella and Carter (1983).