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specimens barcoded:  19243
 
species barcoded:  2779
 
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clusters found: 
858
 
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Collection Protocols
Specimen collection and preservation for barcoding
    The conventional ways of preserving caddisfly specimens include either pinning adults or preservation of larval and adult stages in 80% ethanol. In general, pinned (dried) specimens perform better in preserving DNA. Very large barcode studies (>100K specimens) on Lepidoptera have shown that best results derive from specimens collected within the last 5 years, but it is possible to analyze much older material. However, many specimens (adults and larvae) of Trichoptera are stored in ethanol, where DNA degrades rapidly because of the acidification of ethanol through time. As a result, ethanol preserved specimens should be analyzed within a year or two of capture. Collecting and preserving caddisflies in high concentration ethanol (95%) does slow DNA degradation. Ideally, ethanol should be changed a few days after the initial collection. This is particularly critical for larval specimens because of the large amount of water in their bodies. Other factors, such as temperature and exposure to sunlight can affect the life of DNA as well. Specimens should be kept in a refrigerator when possible.

    Although male adults are preferred, females and immature life stages can also be used especially if they have been identified to species-level. Our recent study on the Trichoptera of the Great Smoky Mountains National Park has shown that life-stage associations for most species were correct. In order to measure the levels of genetic divergence within species, we plan to analyze multiple (>5) individuals for each species. The widest range of intraspecific morphological differentiation from the widest geographic distribution should be included when choosing the particular individuals for DNA analysis.

Museum Materials
    While fresh materials are preferred for establishing DNA barcode library, museum collections may serve as an alternative and critical resource. Although museum materials generally have lower success rate in DNA sequencing, they typically provide much more complete species coverage than new collection efforts. Additionally, freshly collected specimens can be examined against the type specimens that are deposited in various museums over the world using DNA sequences. A series of studies have shown that a very short fragment of COI sequences (~130 bps on the 5' terminus) can provide surprisingly good resolution (>95%) for species-level identification in Lepidoptera as well as in Ephemeroptera, Plecoptera, and Trichoptera (EPT). Because short DNA fragments are much easier to amplify in old specimens, museum materials, including type specimens, can be associated with fresh materials using these "mini-barcodes".

Identification
    Since the Trichoptera Barcode of Life campaign was launched in mid-2007, caddisfly specimens have been contributed from various sources (including amateur collectors and biomonitoring programs), to the CCDB. Researchers at the CCDB have also collected thousands of specimens at varied sites in the eastern half of North America ranging from Hudson Bay to the southern USA. Many of the species encountered still need to have their identifications confirmed by specialists. Certainly, with the help from Trichoptera specialists, the process of collecting reference barcodes for world caddisflies will be greatly accelerated.