Doctoral Dissertations

Date of Award


Degree Type


Degree Name

Doctor of Philosophy


Ecology and Evolutionary Biology

Major Professor

Paris L. Lambdin, Thomas G. Hallam

Committee Members

Jerome F. Grant, Suasn E. Riechert, David A. Etnier


The pit scales or Asterolecaniidae represent a diverse group found in all major biogeographical regions of the world on a variety of host plants. Specimens representing both known and unknown species were obtained from institutions in North and South America for study. Species were described and illustrated based on morphological characters of the adult females. Computer-generated illustrations for each species were developed and stored in electronic files. A key was developed to include the 64 species of pit scales found in North and South America representing 12 genera (Asterodiaspis, Asterolecanium, Bambusaspis, Grammococcus, Mycetococcus, Mycococcus, Neoasterodiaspis, Palmaspis, Planchonia, Pollinia, Russellaspis, and Sclerosococcus). The subfamily Asterolecaniinae contains 56 different species in eight genera (Asterodiaspis, Asterolecanium, Bambusaspis, Grammococcus, Neoasterodiaspis, Palmaspis, Planchonia, and Russellaspis). From these, 48 species in the genera Asterodiaspis, Asterolecanium, Bambusaspis, Neoasterodiaspis, Palmaspis, Planchonia, and Russellaspis were described and illustrated. Because of the presence of recent descriptions, eight species of Grammococcus and Palmaspis were not described, but were included in the key. From the 48 species included in this study, 11 new species (two species of Asterolecanium, five species of Bambusaspis, and four species of Palmaspis) were described and illustrated. Also, three species in the genus Bambusaspis were synonymized and the genus Grammococcus was included in the subfamily Asterolecaniinae. In the U.S., 17 species of the subfamily Asterolecaniinae occur in seven genera (three in Asterodiaspis, four in Asterolecanium, five in Bambusaspis, one in Neoasterodiaspis, one in Palmaspis, two in Planchonia, and one in Russellaspis). From these, 13 species in the genera Asterodiaspis (three species), Bambusaspis (six species), Neoasterodiaspis (one species), Planchonia (two species), and Russellaspis (one species) have been introduced in the U.S. Only Asterolecanium agavis, Al. grandiculum, Al. puteanum, and Palmaspis inlabefacta are considered native to the U.S. The introduced genus Asterodiaspis consists of three species in North and South America feeding exclusively on oaks. The genus Asterolecanium contains 12 species in the New World, including two newly discovered species. Eleven species of the bamboo-feeding genus Bambusaspis are found in the New World including five new species. The two species of the palm-infesting genus Grammococcus are exclusively found in the Neotropics, while the two oak-infesting species of Mycetococcus are restricted to the Western U.S. and Mexico, and Mycococcus coperniciae is known only from palms in Cuba. Neoasterodiaspis adjuncta is an oak-infesting species recorded from New York, which was introduced from Southeast Asia. Some 24 species of the exclusively palm feeding genus Palmaspis have been recorded from the New World including four new species. The introduced genus Planchonia is represented by two species in North and South America. Polliniapollini is an introduced pest in olive growing areas (e.g., California and Argentina) of both continents. In addition, the four species of Sclerosococcus occur on bromeliads in North and South America, and Russellaspis pustulans occurs on over 46 plant families. Computer-generated phylogenetic trees were developed and tested for robustness. The phylogenetic relationships of 38 species in the subfamily Asterolecaniinae were evaluated based on 43 morphological characters of the adult females. A complete consensus tree of the 40 most parsimonious trees was developed. This study suggests that most genera may be monophyletic, while the genera Asterolecanium and Palmaspis appear to be paraphyletic. Pit scale biodiversity has not been adequately investigated, and many additional discoveries of new species are expected from tropical regions.

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