Odd beetle

The Role of the Odd Beetle, Thylodrias contractus, in the Biodeterioration of Museum Objects... 

The odd beetle, Thylodrias contractus (Mots), is an unusual beetle in that it is morphologically very disimilar from its nearest relatives, the phylogenetically related dermestid carpet beetles The adult female odd beetles are wingless and larviform while the adult males are winged and have a body shape unlike all other dermestids. In flight, males resemble small flies. 

This report presents information which clarifies the role of the odd beetle in the biodeterioration of museum objects. A standard form providing documentation of beetle infestations from several museums was compiled to build a data base file on the odd beetle. The purpose of this investigation was to determine the preferred food items and degree of damage to different materials caused by the odd beetle. The results of different treatment methods are compared to assist museum staff in developing a control program. 

A literature search was conducted to obtain as much information as possible on the life history of the odd beetle. This information... 

All institutions reporting infestations of odd beetles were compiled to see if there was a pattern to the data. Table 1 lists each institution and associated information. There is a definite association of University Museums housing insect collections and the presence of odd beetles. The other correlation is the presence of odd beetles in museums housing American Indian artifacts. Table 2... 

A literature search revealed a wide variety of objects infested with odd beetles. Table 3 lists potential food items pulled from this search. The most common source of food listed was dead insects, especially dead moths. Dried animal meat from natural history... 

The odd beetle, contractus subsists on dried animal matter, with dead insects being the most frequently reported food source. Insect and mollusk collections in university museums as well as museums of natural history are most vulnerable to attack by the odd beetle. Almost all infestations in North America can probably be traced to a museum origin. In the past, this beetle was called the tissue paper beetle because it often tunnels through wrappings in its search for food or a place to pupate. The larvae are very active and can be found crawling over many materials. This has misled many to believe that the materials themselves were the food source. 

In museums, the placement of rodent bait stations can lead to outbreaks of odd beetles when the bait is based on dried animal food. The presence of dead insects in a museum can contribute to an odd beetle infestation. The vacuuming of floor areas can reduce the number of dead insects and odd beetles. All windows should be... 

The role of the odd beetle in the biodeterioration of museum objects may be less than that of other dermestids. The odd beetle... 

The museum community can benefit from a data base file on museum pests. Individual museums should be responsible for maintaining complete records of pest infestations. This data can be computerized and analyzed for patterns. Smaller museums would be able to contribute to the solution of common pest problems by sharing this information. Data compiled for the odd beetle has justified this approach. 

Twinn, C.R. (1932). The occurrence of the odd beetle and a brief note on other dermestid species in Canada. Can. Entomol.. 6A, 163-165. 

Review Problem 13 This odd looking molecule (TM 169) is closely related to multistriatin, a phenomone of the elm bark beetle, the insect which spreads Dutch ehn disease. How would you synthesise a sample for testing on the beetle ... 

The //-alkanes usually range in chain length from 21 to 31 or 33 carbons. Hydrocarbons with fewer than 20 carbons commonly occur as pheromones, defensive compounds and intermediates to pheromones and defensive compounds, but their volatility makes them unsuited to function as cuticular components, n-Alkanes have been found on almost every insect species analyzed, and can range from less than one percent of the total hydrocarbons, as in tsetse flies (Nelson and Carlson, 1986 Nelson et al., 1988) to almost all of the hydrocarbon fraction, as in the adult tenebrionid beetle, Eurychora sp. (Lockey, 1985). Depending upon the species, they can consist of essentially only one major component, such as n-pentacosane in the American cockroach, Periplaneta americana (Jackson, 1972) to a series of //-alkanes, such as the series from C23 to C33 in the housefly, Musca domes-tica (Nelson et al., 1981), with trace amounts to C37 (Mpuru et al., 2001). In all cases, the odd-numbered alkanes predominate, due to their formation from mostly two carbon units followed by a decarboxylation (Blomquist, Chapter 3, this book). Small amounts of even-numbered carbon chain //-alkanes often occur, and presumably arise from chain initiation with a propionyl-CoA rather than an acetyl-CoA. Occasionally, gas chromatographic analyses reveal similar amounts of even-numbered chain //-alkanes and odd-numbered chain components. This is a red flag that the samples must be checked for contamination. 

Another common type of dimethylalkane is the 2,X-, 3,X-, 4,X-, and 5-X dimethylalkane, where X is the second methyl-branch position and is separated from the first methyl-branch by an odd number of carbons. These dimethylalkanes usually occur as mixtures of isomers with 3,5,7,9 or 11 methylenes between the methyl branches. In the Colorado potato beetle, Leptinotarsa decemlineata, forty percent of the egg hydrocarbons were comprised of 2,X-dimethylalkanes, with the most abundant being 2,10- and 2,6-dimethyloctacosane (Nelson et al 2003). 

Diols have been rarely observed in insect cuticular lipids (Buckner, 1993). Odd-carbon-number diols (C23-C29) were the major lipid class (55%) of the larval cuticular lipids from the flour beetle, Tenebrio molitor (Bursell and Clements, 1967). The major diol constituent was 8, 9-pentacosanediol. For the cuticular lipids of M. sexta larvae, very small amounts (<1%) of 7,8- and 8,9-C27 diols and 8,9- and 9,10-C29 diols were identified (Espelie and Bernays, 1989). Hydroxy n-alkanols are diols with a hydroxyl functional group on the C, position (terminal) of the alkyl chain, but are technically not alcohol derivatives of hydrocarbons. There are a few reports of the occurrence of insect hydroxy -alkanols (Buckner, 1993 Nelson and Blomquist, 1995 Buckner et al., 1996). In a structure analysis study of beeswax, the major alcohol moieties of the diester fraction were identified as 1,23-tetracosanediol (42.2%), 1,27-octacosanediol (26.0%) and 1,25-hexacosanediol (20.2%) (Tulloch, 1971). The hydroxy n-alkanols comprised 16% of the cuticular lipids of FI. zea pupae and were identified as C30-C36 even-chain n-alcohols with hydroxyl groups on carbon numbers 11, 12, 13, 14, or 15 (Buckner et al., 1996). Mass spectral analysis indicated the presence of unsaturation in the alkyl chain of the major diol components. 

In comparing the results of Ae two sets of experiments, it will be seen that red thyme was 41% less effective against LBAM than white thyme and in controlling Flour Beetle there was, in comparison, a 65% difference between the two botanical cultivars. Furthermore, the effectiveness of the essential oils drops off rapidly so that only eucalyptus, camphor, and white thyme may be considered as useful canidates. Oddly, black pepper was inactive in these assays, while in earlier work certain components of this commodity have been shown to have strong insecticidal properties. The earliest report being in 1943 (12), which was followed not only by later reports of insecticidal... 

Barber, H.S. (1947). On the odd, or tissue-paper beetle, supposed to be Thylodrias contractus. Ann. Entomol. Soc. 

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