We have finished imaging more than 5,700 Madagascan butterfly and moth (Lepidoptera) type specimens in the Museum’s collection. Once these specimens have had their associated data labels transcribed, they will be released freely and openly onto the Museum’s Data Portal for worldwide use by scientists and others.
Madagascar is a key global biodiversity hotspot, home to some of the richest and most unique insect biodiversity on the planet. Almost 5,000 butterfly and moth species are described from the island. Alarmingly, it is estimated that almost half of the forest cover present in 1950 in Madagascar has already been lost. Moths and butterflies, are particularly sensitive to environmental changes e.g. larvae may depend on a particular plant at a particular stage of its life cycle to provide their food. Madagascan lepidoptera include many species known only from one or a few localities on the island. This high level of local uniqueness makes them an ideal group for scientists to study to understand the impact of disappearing habitat on species.
We have comprehensively digitised Madagascan Lepidoptera type specimens from the Museum’s collection and will release this information openly on the Museum’s Data Portal. Openly releasing this data will enable users to identify species (both in the field and in other museum collections) more reliably than was possible before. This will allow scientists to compile local lists of observations and track how these species are adapting to the changing habitat, thus informing future conservation plans.
This project started in Autumn 2017 with support from John Franks, the Charles Wolfson Charitable Trust. The work to complete the project continued in 2018 with Digital Collections hosting a BEIS funded Rutherford Fellow who continued the digitisation work. The initial estimate was that the Museum held around 1,700 Madagascan Lepidoptera types; however, whilst preparing to digitise, we have actually pulled out over 5,700 specimens in total.
This project is only looking at type specimens. This is sometimes a single specimen, sometimes a series of specimens. These type specimens are of crucial scientific importance as they are the example specimens on which a species is based.
Type specimens are particularly useful to researchers. Comparing a newly observed specimen to a type helps researchers identify species correctly Digitising types also allows for them to be verified – in many instances the scientific consensus on the genus may have changed since the original description. And a searchable, digital resource also provides information about when a new species has been discovered.
As the Museum’s collection is arranged taxonomically, each type specimen sits within a drawer containing non-type specimens of the same genus. The collections are spread over a number of floors and collections areas which means that selecting only the type specimens is significantly slower than if we were digitising the collection in taxonomical order. For this project, after finding them all, we have re-curated all the Madagascar type specimens in a single arrangement by original genus and species. This greatly speeds up access to these type specimens in our collection in future.
What’s in a name?
During the first part of the project, our digitisers were spending around a third of their time looking for the specimens in the collection. This took time away from imaging. This was further complicated when looking for type specimens that were put aside at the start of the second world war. At this dangerous time, collections were sometimes assembled and sent off site without detailed checks or ‘type’ labelling. To find out which specimens we really needed to digitise required detailed work with the curators and consultation of the original literature. As part of this project, we have developed a new pipeline for finding and verifying type specimens in the Museum’s collection.
The curators use their databases of Madagascan specimens to first compile a checklist of what type specimens we know we should have in the collection; they then cross-compare this list with the literature from the Museum’s libraries to source the original description of each species as well as historical evidence for the actual museum it was deposited. This process has allowed us to uncover more type specimens in the collection than we originally knew about. With a list of names in the hand of every curator, some also were found by a detailed or exhaustive search of likely locations within our collection. The literature links, especially those in the Museum’s own Biodiversity Heritage Library, have also been assembled to enable scientists to drill down quickly to the exact page source for each species name.
Labels can accumulate over time on a specimen as scientists add more and more information. These new labels are retained along with the original ones available at the time of description, and are kept as part of that specimen’s history. This can leave us with a lot of labels to capture digitally when imaging that specimen. The most labels we have found on a specimen since the digital collections programme started in 2014 has been a specimen from this project; Ypthima batesii, a Madagascan butterfly now in the genus Strabena in the nymphalid subfamily Satyrinae which bore 17 labels. This included colour copies of some beautiful illustrations painted from the original specimen and included in the Felders’ original description
“We delight in the beauty of the butterfly, but rarely admit the changes it has gone through to achieve that beauty.” Maya Angelou
Around 85% of the specimens digitised as part of the project were pinned specimens like the example shown above. Others were preparations of parts of the specimens. To find out more about the technique we used to digitise pinned specimens, you can take a look at our previous blog post: Digitising the Madagascan Lepidoptera type specimens.
After digitising the pinned specimens, the remainder of the collection (around 600 items) was digitised. These consisted of parts of specimens, usually genitalia, either mounted on glass slides or housed within vials. These parts were usually separated from the rest of the pinned insect. In the past especially, the most important parts used for distinguishing one species from another were its genitalia. In most cases, these dissections and preparations were made well after the original description. As the genitalia are still regarded as a particularly important feature for reliably identifying species, which should match the type specimens in detail if they really belong to the same species, we will include this valuable information online.
We have flexible digitisation set ups to cope with the large variety of specimens imaged across the collection. We were able to use our slide workflow that has been perfected during our previous lice digitisation project to image the slides and vials needed to complete the Madagascan Lepidoptera digitisation project.
To find out more about Madagascan moths and butterflies, please take a look at our previous blogpost and keep your eye out on our Twitter for news about the release of our Madagascan type specimen data to the Museum’s Data Portal.
This project is a pilot on the digitisation of pinned insect type specimens. All our previous pinned insect projects have included both type and non-type specimens mixed together. Therefore, the learning from this project will help inform future digitisation of types for the Museum. To find out more about the Digital Collections visit the Museum’s website.