The larvae of the British species of Psychoda (Diptera: Psychodidae)

Abstract

In Britain the genus Psychoda Latr. contains sixteen species and two subspecies (Kloet & Hincks, 1945), the larvae of which occur in cow dung, decaying vegetation, and the bacteria beds of sewage purification works. A knowledge of these larvae would be useful both to the sewage biologist and the sanitary inspector, but for only three species have the larvae been fully described. Two of these, Psychoda alternata Say, and Ps. cinerea Banks, are inhabitants of the bacteria bed, and the larva of the former has been described on at least six occasions, the classical account being that of Dell (1905). The larva of Ps. cinerea has been described three times, the most complete account being that of Malloch (1917). The third Psychoda larva of which we have a full account is Ps. albipennis Zett. (Keilin & Tate, 1937), a species inhabiting dung and decaying vegetation. In addition to the foregoing there is a brief and inadequate description of the larva of Ps. severini Tonn. (Johnson, 1914), a species which is commonly present in the bacteria bed.