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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Studies of the Passive Dispersal of Viable Algae and Protozoa by Aquatic and Terrestrial Beetles

Milliger, Larry Edward 08 1900 (has links)
The purpose of the present study was to determine the relative importance of aquatic and terrestrial beetles as possible vehicles in the passive overland dispersal of viable microorganisms.
52

The biology and ecology of the corn seed beetle (Agonoderus pallipes Fab.)

Dillon, George Franklin. January 1938 (has links)
Call number: LD2668 .T4 1938 D51
53

Distribution and reproduction of dung beetles in a varying environment : implications for conservation of semi-natural grasslands /

Vessby, Karolina. January 2001 (has links)
Thesis (Ph. D.)--Swedish University of Agricultural Sciences, 2001. / Thesis statement in Swedish and English abstract inserted. Includes bibliographical references.
54

Pre- and post-copulatory sexual selection in the tortoise beetle Acromis Sparsa (Coleoptera Chrysomelidae)

Trillo, Paula Alejandra. January 2008 (has links) (PDF)
Thesis (Ph.D.) -- University of Montana, 2008. / Title from author supplied metadata. Description based on contents viewed on July 15, 2009. Includes bibliographical references.
55

Habitat use and population spatial structure of the Forked Fungus Beetle (Bolitotherus cornutus Panzer /

Teichert, Sonja. January 1900 (has links) (PDF)
Thesis (M.Sc.)--Acadia University, 1999. / Includes bibliographical references (leaf110). Also available on the Internet via the World Wide Web.
56

The endocoprid dung beetles of southern Africa (Coleoptera: Scarabaeidae)

Davis, Adrian L V (Adrian Louis Victor) January 1978 (has links)
The biology and ecology of the endocoprid dung beetles of the Aethiopian zoogeographic region has been studied in the field and laboratory. Work has centred mainly on Oniticellus planatus and O. formoaus although infomation has also been supplied on O. egregius, O. pictus and Tragiscus dimidiatus. The taxonomy of Onticellus (s.str.) and Tragiscus has been discussed with the recommendation that O. planattus and O. pseudaplanatus be synonymised. It has been suggested that endocoprid distribution is chiefly controlled by temperature, rainfall and the density of suitable large dung masses. On the basis of distribution it has been suggested that the taxonomic status of the subspecies of O. pictus should be reviewed. Endocoprids (genus Oniticellus (s.str.) are found throughout the warmer regions of Africa and Asia. Tragiscus is found only in Africa. Methods are described for monitoring endocoprids in the field, for distinguishing freshly emerged from older specimens, and for breeding endocoprids under laboratory conditions. It has been shown that endocoprids breed within or just beneath large dung masses unlike most other members of the Scarabaeinae which actively bury dung and construct the their broods at depth in the soil. It has been shown that there is a restriction of breeding sites available to endocoprids due to the removal of dung by the Scarabaeinae beetles and the limited space available within dung pads. This has resulted in low endocoprid population numbers, a disadvantage, which has been countered by highly specialised but opportunistic breeding habits. The requirements of dung plasticity have limited the time available for breeding activity by most endocoprids (excluding O. egresius) so that both the reproductive system and the reproductive behaviour (cf. O. planatus) are geared to rapid egg and brood production. Large numbers of follicles are able to be produced over a short period. In the probable absence of feeding, this has possibly been allowed by the involvement of a well developed fat body. The broods are tended by the parent female during larval development and the follicles are gradually resorbed, probably to prevent starvation. Ovarian recovery is rapid once feeding recommences. Behavioural mechanisms have developed which boost the number of broods constructed and the rapidity with which they are produced. The duration of endocoprid colonisation and the timing of arrival at dung is shown to be related to the rate of pad desiccation which is chiefly controlled by temperature and degree of dung removal by other dung beetles. Precipitation may also play a part. Predation by vertebrates and other insects has been noted and a number of mechanisms are described which are probably protective. Two insect parasitoids of O. formosus larvae have been recorded. The potential use of endocoprids in the Australian dung and fly control project has been discussed and it is recommended that their introduction be considered of low priority. It is suggested that the endocoprids evolved from Euoniticellus type ancestors and that their behaviour complex nidification developed in response to harsh environmental factors, chiefly the danger of desiccation and competition for dung with other dung beetles. From a consideration of brood and brood chamber construction it is suggested that O. egresius is a relatively unspecialised endocoprid which may retain dry season aestivation and has not evolved much further than its probable Euoniticellus type ancestor. The broods are coated in clay and abandoned soon after construction. Greater specialisation is shown by O. planatus and O. formosus which exhibit brooding behaviour, increasing longevity, more specialised brood protection, increased potential fecundity and continuous activity throughout the year. O. formosus shows greater specialisation in brood production than O. planatus. Greatest specialisation is found in T. dimidiatus which exhibits a precise brooding period and low egg production. Brood construction is of a similar degree of specialisation to that of O. formosus. Activity is also continuous throughout the year. The comparative biology of the five southern African endocoprids is summarised in Table 35. Summary, p. 129-131.
57

Study of the aquatic and semiaquatic coleoptera in the state of Utah

Chandler, Harry P. 01 May 1941 (has links)
The purpose of this paper is to discover and make known the species of aquatic and semiaquatic Coleopters of the sub-order ADEPHAGA which occur in Utah and to give something of their distribution, environment and habits whenever possible. When ever possible the original description or a description from a recent revision has been included for each species. Descriptions given in recent revisions have been regarded as more desirable because they describe the species in comparison with its nearest relatives, while many fo the original descriptions were very incomplete and could not be used to separate many of our present species or even genera, if the types were not known.
58

A morphological and systematical study of the genus Brachinus of the United States

Brown, Almon L.D. 01 May 1932 (has links)
The genus Brachinus belongs to the well-known family Carabidae, commonly known as "Ground Beetles". About 15,000 species of Carabidae have been described, of which over 100 genera and 1,200 species occur in the United States. (Dodd Mead 1928).
59

Bionomics of two aspen bark beetles : Trypophloeus populi and Procryphalus mucronatus (coleoptera:scolytidae)

Petty, Jerold L. 21 July 1976 (has links)
Beetles of Trypophloeus populi attacked green bark of unhealthy aspen (Populus tremuloides) and hastened the death of the tree. Beetles of Procryphalus mucronatus favored dead bark and were of little significance in the death of the aspen. These two beetle species were distinguished from each other by their primary galleries, eggs, larvae, larval mines, and mating behavior. In T. populi, there were three larval instars and one to one and one-half generations per year; only larvae overwintered, and the eggs of the first generation were present by mid-July. In P. mucronatus, there were two larval instars and one and one-half to two generations per year; both larvae and adults overwintered, and the first eggs of the new season were present by late May.
60

Resistance of cucurbit seedling to cucumber beetle feeding

Nath, Prem,1937- January 1960 (has links)
Call number: LD2668 .T4 1960 M87

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