Tremblay, E., Rotundo, G., & Tranfaglia, A. 1983 [Planococcus citri (Ris.) and Planococcus ficus (Sign.), a case of speciation in progress.] Planococcus citri (Ris.) and Planococcus ficus (Sign.), un caso di speciazione in atto.. Atti XII Congresso Nazionale Italiano di Entomologia 2: 435-438.

Notes: [Conference held in Rome 5-9 November 1980.] Planococcus citri (Risso) and P. ficus (Sign.) both infest fig and grapevine in Italy, and their females are very similar morphologically and serologically, but female species-specific sex pheromones favour homogamic mating. In the laboratory, heterogamic mating was induced by sex pheromones extracted from virgin females of both species. F1 hybrids of both types were viable, but females predominated. The F1 males were sexually attracted by their sisters and by virgin females of the maternal species but not by those of the paternal species. F1 females attracted F1 males and males of both parental species and are concluded to release the sex pheromones of both species. Genetic reasons are given for the unattractiveness of the paternal species for the F1 hybrid males. Morphological identification of hybrids was possible only at population level, by analysing the frequencies of key characters such as the number of tubular ducts of the ceraria on the head of the female. It is concluded that the process of speciation in these 2 taxa is still incomplete and in progress.