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Browsing by Author "Howell, James O."

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    Morphology and systematics of the adult females of the genus Lecanodiaspis (Homoptera: Coccoidea: Lecanodiaspididae)
    Howell, James O. (Virginia Polytechnic Institute and State University, 1971)
    In the past, the systematics of species in the genus Lecanodiasuis has been chaotic. This study is an attempt to clarify the classification of this group. Forty-eight species are included in this paper; six of these are new species and described for the first time. Adult females of thirty-two species are fully described and illustrated, and measurements are included for various morphological characters. Keys are provided for the separation of 46 species. Material for this study was borrowed from numerous collections around the world. Various mounting techniques are described and compared. The external morphology of the adult females is varied. In general there are eight or nine-segmented antennae; rudimentary, one-segmented legs; two pair of thoracic spiracles with 5-locular pores in the spiracular furrows; fleshy spiracular setae anteriorly and posteriorly; seven transverse rows of multilocular pores on the abdomen; dorsal anal plates, and anal ring with eight to ten setae; dorsum and venter with numerous 8-shaped and simple pores, with numerous tubular ducts dorsally, fewer ventrally; and a single, elongate apical seta on each anal lobe. The genus is divided into five species groups based on morphological characters, geographical distribution, and host records. Maps are given for the distribution of species within each group, and affinities are given for each species at the end of its description. A suggested phylogenetic tree for all species in the genus is given, and the phylogeny of the genera in the family Lecanodiaspididae is briefly discussed. Host relationships within and between groups are given. The biology of L. prosopidis was studied on two different hosts. This species overwinters in the egg stage inside the waxy test of the adult female. First instar nymphs hatch from eggs outdoors about May 15, and settle after a few days. Second instar nymphs were collected on July 7, with sexual dimorphism evident. hci.les had emerged. by August 6, and egg deposition had occurred by September 18.
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    Spiders of alfalfa with notes on the biology of Tetragnatha laboriosa Hentz
    Howell, James O. (Virginia Tech, 1969-04-05)
    Several areas of the bionomics of spiders of alfalfa in Virginia were given preliminary investigation. The species complex of the spider fauna was determined and the seasonal occurrence of the four major species were plotted. The D-Vac sampler and the sweep net were the major sampling methods utilized. Fourteen families consisting of 75 genera and 112 identifiable species were found. Tetragnatha laboriosa Hentz, Pachygnatha tristriata Koch, Misumenops asperatus (Hentz) and Oxyopes salticus Hentz were the most common species found.