Title page for ETD etd-07112009-040603

Type of Document Dissertation
Author Knausenberger, Walter Ingolf
URN etd-07112009-040603
Title Contributions to the autecology and ecosystematics of immature ceratopogonidae (Diptera), with emphasis on the tribes heteromyiini and sphaeromiini in the middle atlantic United States
Degree PhD
Department Entomology
Advisory Committee
Advisor Name Title
Turner, E. Craig Jr. Committee Chair
Benfield, Ernest Fredrick Committee Member
Hoffman, Richard L. Committee Member
Kosztarab, Michael Committee Member
Voshell, J. Reese Jr. Committee Member
  • Diptera
Date of Defense 1986-12-05
Availability unrestricted

Biological and systematic study of the immature stages of the biting midges (Diptera: Ceratopogonidae) has been infrequent, although the family is one of the largest in the order, with over 4,000 species worldwide, and is ubiquitous among aquatic/semiaquatic environments. An ecosystematic analysis is presented here of the Ceratopogonidae in Virginia and contiguous states based mainly on a diversified biological field survey, with particular attention to associating immature stages with adults, and acquisition of ecological data. I emphasized (a) extraction of larvae and pupae; (b) two methods of rearing, developed for this study: individual rearing(IR) with an agar-nematode technique, and collective rearing from the habitat substrate in rearing cartons(RC); and (c) field trapping of adults at the habitats.

In Section I, a faunistic assessment - the first of its sort - is provided of the total Virginia-region ceratopogonid fauna, in all developmental stages, with a focus on Culicoides, including a comparative evaluation of the relative abundance of the ceratopogonid genera with respect to methods of collecting and extracting.

High taxonomic richness of the ceratopogonid fauna in the Middle Atlantic states is reflected in the 150 described and 42 undescribed (new) species recovered. A detailed geographic checklist for the 222 species of Virginia and the five contiguous states is presented and interpreted. At least 54 Culicoides species are present in the Middle Atlantic u.s. About half of the larval species can be determined in Virginia. With the results of this study, 93% of breeding sites for the genus are known in Virginia, more than for any other state.

Section II assembles and synopsizes data on the autecology, life history, habitat, morphology, systematics, as well as geographic and seasonal occurrence of 28 species (3 new) and 10 genera in two related tribes of predaceous biting midges, Heteromyiini and Sphaeromiini (subfamily Ceratopogoninae). Shorelines are the "archetypical arena" in which these larvae thrive, typically above and below the water line. Their habitats and substrates are characterized in detail. The greatest diversity of larvae in these tribes consistently occurs in and along mid-reach streams{Order: 3 to 5).

Mechanisms of ecological partitioning by sympatric species, and the differential adaptive significance of larval, pupal and adult morphological characters are evaluated. Taxonomic and ecological diversity in these groups are clearly related.

  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  LD5655.V856_1986.K53.pdf 34.53 Mb 02:39:50 01:22:12 01:11:55 00:35:57 00:03:04
[BTD] next to an author's name indicates that all files or directories associated with their ETD are accessible from the Virginia Tech campus network only.

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.