New mutants and their chromosome assignment in the fly Megaselia scalaris.

We describe six new mutants, spontaneous or EMS-induced, and a previously isolated radiation-induced mutant of Megaselia scalaris Loew (Diptera, Phoridae). Five are eye-color mutants, one affects the segmentation of the abdomen, and one disturbs the regular form and arrangement of ommatidia in the compound eye. A complementation test exposed two pairs of alleles among the five eye-color mutants, leaving three different loci that affect eye pigmentation.

Ecdysone and a dietary alkaloid interact in the development of the pheromone gland of a male moth (Creatonotos, Lepidoptera: Arctiidae).

Hair-covered scent organs of the male arctiid moth Creatonotos produce and dissipate the volatile pheromone hydroxydanaidal. The biosynthesis of this substance depends quantitatively upon the uptake of pyrrolizidine alkaloids (PA) with the larval foodplant. The size of the tubular, eversible scent organ (corema) is also positively correlated with the ingested amount of the same alkaloid, which acts like a specific growth factor.

Evidence for the priming role of the central retinula cell in ommatidium differentiation of Ephestia kuehniella.

In the developing compound eye of Ephestia kuehniella, within the advancing front of differentiation, regular cell clusters arise which consist of a central cell and two flanking cells. The central cell is destined to become the basal retinula cell later in development. Its crucial role in ommatidium formation is confirmed by H-thymidine labelling.

[The effect of ethidium bromide on ommatidium development inEphestia kühniella zeller].

1. The effect of ethidium bromide (EB) on ommatidium development inEphestia was investigated. Doses ranged from 10 to 10 μg EB/pupa.