A Classification of Coleoptera in 3D

1939-sc-pub-1The Freshwater Biological Association has a long history of publishing identification keys. Its first Scientific Publication, A Key to the British Species of Corixidae (Hemiptera-Heteroptera) with Notes on their Distribution, was published in 1939 by FBA entomologist Thomas T. Macan (1910-1985).

Macan worked at the FBA throughout his distinguished career from 1935 to 1976, focusing on freshwater invertebrates. He published a number of other Keys for the FBA Scientific Publications (see below), and the FBA holds in its archives his drafts and drawings for these publications, as well as the notebooks and surveys which he conducted throughout his career. The FBA also holds the numerous insects Macan collected, both as pinned specimens and as invertebrates preserved in alcohol. Many of these specimens were used for the research and writing up of the FBA Keys and thus form an invaluable reference to accompany some of the Scientific Publications. Macan was a meticulous collector, carefully labelling his pinned or fluid-preserved specimens with date, place of collection, name of collector and species name.

While undertaking a survey of the FBA’s invertebrate collection, amongst other boxes of pinned insect specimens, I stumbled upon a box entitled ‘Classification of Coleoptera’. It is nothing short of a 3-D key for the identification of Coleoptera and it includes aquatic and terrestrial beetles.


Different coloured threads enable the user to differentiate between the two sub-families of Adephaga (red thread) and Polyphaga (green thread) within the top side of the box.


The lower half distinguishes between five superfamilies, some names of which have now changed.


Macan’s precise drawings on small cards give detailed description of characteristics such as wing venation or antenna structure that guide the identification process. At the end of each thread is a pinned specimen, with details of its collection annotated in minuscule handwriting on a tiny label.


The specimens were collected between 1929 and 1932 around Cambridgeshire (Cambridge itself, where Macan was educated in the early 1930s, Bottisham Fen, Wicken Fen, Roman Road and Fleam Dyke), Norfolk (Blakeney Point, Breckland), and in Tollesbury (Essex).


Dating to Macan’s student days, the ‘Classification of Coleoptera’ box is clearly the effort of a student and budding entomologist intent on learning classification and taxonomy. It demonstrates the ability of visual techniques to trigger memorisation and learning. The effort invested in planning the layout of the box, laying out the threads, collecting and pinning the insects in their allocated place, drawing the distinctive characteristics, annotating the labels, would have paid off in the memorisation of the classification of the largest order in the class Insecta.

The box is also a precursor to the extensive taxonomical and classificatory work Macan later undertook at the FBA, the outcome of which was the numerous and lasting Keys published by him and his colleagues.

Isabelle Charmantier, Information Scientist



T.T. Macan published a number of Keys for the FBA, which include:

  • 1941. A Key to the British Water Bugs (Hemiptera-Heteroptera excluding Corixidae). Freshwater Biological Association, Ambleside, UK.
  • 1949. A Key to the British Fresh- and Brackish-Water Gastropods. Freshwater Biological Association, Ambleside, UK.
  • 1956: A Revised Key to the British Water Bugs (Hemiptera-Heteroptera). Freshwater Biological Association, Ambleside, UK.
  • 1960: A Key to the British Species of Crustacea: Malacostraca Occurring in Freshwater: With Notes on Their Ecology and Distribution (with H. B. N. Hynes and W. D. Williams). Freshwater Biological Association, Ambleside, UK.
  • 1967: Key to the British Species of Freshwater Cladocera (with David Joseph Scourfield).
  • 1973: Key to the Adults of the British Trichoptera. Freshwater Biological Association, Ambleside, UK. ISBN 978-0900386190
  • 1977: A Key to the British Fresh and Brackish Water Gastropods. Freshwater Biological Association, Ambleside, UK. ISBN 978-0900386053
  • 1979: A Key to the Nymphs of the British Species of Ephemeroptera: With Notes on Their Ecology. Freshwater Biological Association, Ambleside, UK. ISBN 978-0900386350
  • 1988: Larvae of the British Ephemeroptera: A Key with Ecological Notes (with J. M. Elliott and U. H. Humpesch). Freshwater Biological Association, Ambleside, UK. ISBN 978-0900386473

In 2012, the Guide to Freshwater Invertebrates was written by staff from the Freshwater Biological Association, as a tribute to T.T. Macan, one of the ‘founding fathers’ of freshwater biology.

The FBA’s Scientific Publications can be browsed and are available for purchase at http://www.fba.org.uk/scientific-publications-sps