Equipment and Preservation

Equipment and chemicals for Myriapods and Isopods

In a short contribution to the BMIG Newsletter, Spring 2006, Paul Lee offered the following advice on basic equipment and chemicals for collecting, preserving and identifying myriapods and isopods.

  • A stereo microscope capable of producing good quality images at magnifications of at least x30 and ideally up to x100;
  • A light source of sufficient intensity for the microscope;
  • An excavated glass block for holding specimens in alcohol whilst viewing them under the microscope;
  • A pair of soft forceps for manipulating specimens without damaging them;
  • A very fine mounted needle (a headless entomological pin in a pin vice is ideal) for manipulation and dissection of specimens;
  • A supply of glass specimen tubes (I find 12x50mm tubes with polythene stoppers to be most suitable) for collection and storage of preserved specimens;
  • A quantity of preservative, either industrial denatured alchohol (IDA) (this used to be known as industrial methylated spirits - IMS) or iso-propyl alcohol, diluted with distilled water to 70%.

Many invertebrate workers use IDA as their preservative of choice.  However, whereas iso-propyl alcohol can be bought by anyone, the receipt and use of IDA requires authorisation from the National Registration Unit of HM Revenue & Customs. Further information can be found in their Notice 473: Production, distribution and use of denatured alcohol. This document can be downloaded from their website: (Type ‘IDA’ into the search box to find the relevant page.)

Alternatively you can phone 0845 010 9000 to obtain a paper copy.  It includes an application form for authorisation which requires you to give your name, address etc, to state the purpose for which the IDA will be used and your annual requirement in litres. Provided you apply for authorisation of no more than 20 litres per annum (more than adequate for BMIG members) an application to use IDA “for the preservation of biological specimens for scientific study only” will normally be approved. If this is the case you will receive a formal letter of authorisation. Having received authorisation you should be aware that  HMRC officers have the right to inspect the premises where you use IDA at any time although this very rarely happens.

When purchasing IDA your supplier will need a copy of your authorisation letter. You can obtain IDA through specialist laboratory chemical suppliers although not all are willing to deal with members of the public and / or to provide small quantities. Alternatively local High Street pharmacies may be able to help. Entomological equipment suppliers tend not to sell IDA because it cannot be sent by post.