Takagi, S. 2008a A fifth species of Chionandaspis, with reference to the significance of monotypic genera (Sternorrhyncha: Coccoidea: Diaspididae). . Insecta Matsumurana (New Series) 64: 117-126

Notes: Chionandaspis glutae, sp. nov., of which the female burrows into the leaf epidermis of Gluta elegans, is described from Penang Island, Malaya, Malaysia. Among the five known species of the genus, C. glutae is the most derivative in having fused median trullae in the adult and second-instar females, which are, thus, highly adapted to burrowing. Chionandaspis as a whole is a peculiar genus composed of burrowing species, but includes a less peculiar species, C. 9IKc-H. Starting with this species, some characters in the adult females change in succession through the five species. Other characters show a gap between C. 91Kc-H and the other species and another gap between the twig-inhabiting C. ramicola and the leaf-associated C. Joliicola, C. palawanensis, and C. glutae. The known species of the genus represent a primitive form associated with the twigs and derivative forms differentiated in adaptation to the burrowing mode of life on the twigs and on the leaves. Many genera have recently been erected for isolated species of burrowing diaspidids, whereas monotypic genera remain problematical. Chionandaspis shows that even peculiar genera may arise with less peculiar species and, once established, may promote adaptive speciation. If this generalization is adopted, the problem of monotypic genera may be concerned with the dimensions of the adaptive zones they exploit rather than with their morphological peculiarities or the mechanisms by which they emerge.