Molecular phylogeny of the family Coccidae (Hemiptera,Coccomorpha), with a discussion of their waxy ovisacs

Coccidae is one of the major families of scale insects, with many species considered to be serious agricultural or horticultural pests. However, the phylogenetic relationships among coccid subfamilies, tribes and genera are poorly understood because existing hypotheses are based on morphological characters and cladistic analyses. Here, we present the first molecular phylogeny of the family Coccidae based on DNA fragments of a mitochondrial gene (COI), nuclear ribosomal RNA genes (18S and 28S), and elongation factor-1α (EF-1α). We found that some genera (Coccus Linnaeus and Pulvinaria Targioni Tozzetti), tribes (Coccini, Paralecaniini, Pulvinariini and Saissetiini) and subfamilies (Coccinae and Filippiinae) within the family are nonmonophyletic. Formation of a waxy ovisac and the distribution and structures of ventral tubular ducts have been used to define the tribe Pulvinariini morphologically; however, these were found to be homoplastic traits based on ancestral state reconstruction. Accordingly, we propose a new classification of certain groups as follows: (i) the Paralecaniini is raised to subfamily rank, Paralecaniinae stat.n. , except that Neosaissetia Tao, Wong & Chang is retained as a member of Coccinae; (ii) Megapulvinaria Yang and Pulvinarisca Borchsenius are transferred from Coccinae to Pulvinariscinae stat.n. ; and (iii) Metaceronema Takahashi is transferred from Filippiinae to Pulvinariscinae stat.n. We provide amended diagnoses for the newly proposed subfamilies.