Preservation of hymenopteran specimens for subsequent molecular and morphological study

Abstract

Some guidelines are presented for long‐term preservation of insects for non‐traditional systematic studies such as DNA sequencing and internal anatomical research. The main criteria for good DNA preservation appear to be the rapidity with which the DNA is protected from enzymatic and chemical breakdown, and subsequent storage conditions. The immediate post mortem treatment of specimens appears particularly important to the preservation of amplifiable DNA. For storage we recommend 70–100% ethanol at low temperature, deep freezing, and critical point or chemical drying direct from alcohol. For internal anatomy, traditional fixatives, 70% ethanol in a refrigerator, critical point drying or chemical drying are recommended. Cold‐storage in 70% ethanol with or without subsequent critical point drying or chemical drying using hexamethyldisilazane allow both molecular and morphological study.

Field and Laboratory Methods for DNA Studies on Deep-sea Isopod Crustaceans

“…Although we cannot prove this statistically, the cooling chain and fresh tissue may be regarded as essential for a high success rate. However, there is evidence (not shown here) suggesting that ac− ceptable results might be possible even after two years of storage as long as the samples were constantly kept in chilled conditions as recommended for various other taxa (Quicke et al 1999;Gemeinholzer et al 2010;Nagy 2010).…”

The use of Proteinase K to access genitalia morphology, vouchering and DNA extraction in minute wasps

“…Glycerin preserves tissues better than dryness (Quicke et al 1999) and does not inhibit PCR reagents. It could be a source of genomic data even in destroyed collection exemplars.…”

Description of two techniques to increase efficiency in processing and curating minute arthropods, with special reference to parasitic Hymenoptera

“…specimen age, dehydration technique) for DNA recovery (Junqueira et al 2002). Nevertheless, the speed at which the internal tissues dry can affect the ultimate state of preservation of DNA for subsequent genomic extraction (Quicke et al 1999;Nagy 2010). The HMDS dehydration method, along with other chemical-based techniques, is demonstrated to yield high quality genomic DNA (Austin and Dillon 1997); some DNA sequence data in Buffington et al (2007), using the chelex extraction protocol, was generated from cynipoid specimens that were vacuum dried in the manner summarized here, but no quantification of success vs. failure of DNA amplification was documented.…”

“…Both of these fractions must be dealt with in an efficacious manner to ensure maximal preservation of the morphological and genomic information of the specimens (Quicke et al 1999). By using novel, inexpensive separation techniques (Buffington and Gates 2008), and volunteer labor (where possible), samples can be processed and made available for research.…”