butterflies

A provisional checklist of European butterfly larval foodplants

For the first time, a list of the currently accepted plant names utilised by 471 European butterfly larvae is presented, with references.

Guest blog post by Harry E. Clarke, Independent Researcher

5th instar Swallowtail larvae feeding on Milk-parsley.

Many books on butterflies publish lists of their larval foodplants. However, many of these lists of larval foodplants have been copied from previous lists, which in turn have been copied from previous lists. Consequently, errors have crept in, and many plant names have long been superseded. This can result in duplicates in the list, with the same plant being given two different names. Most plant lists do not include the authority, which can make it difficult or impossible to identify which plant is being referred to. Some of these plants may not be used by butterflies in Europe, but elsewhere in their range. Or the plants may have been used in breeding experiments, but not used by the butterflies in the wild.

Many of these publications providing the larval foodplants of butterflies only provide the binomial name, without specifying the author. This can create problems in knowing which species of plant is being used, as the same plant name has been used in the past by different authors to describe different species. In some cases, distribution can be used to determine the correct species, but plants can often have similar distributions. For example, in the World Checklist of Vascular Plants, there are 40 entries for the plant with the scientific name Centaurea paniculata, which refer to thirteen different accepted species, depending on authors, subspecies, and variety or form.

Not quite so simple: updating the current lists of larval foodplants

With climate change and habitat loss threatening numerous species, the conservation of butterflies (and other animals) is becoming more important. Whilst many factors determine the distribution of butterflies, such as temperature and rainfall, their survival depends solely on the kinds of plants their larvae eat. Accurate lists of larval foodplants are therefore important to find out where to direct limited conservation resources for the best result.

What started out as a straightforward job of updating the existing lists of larval foodplants with currently accepted names turned out to be a far bigger job. Many of the lists are incomplete, and may vary throughout the range of the butterfly. Here, errors have crept in too. Many references provide incomplete, unverifiable information. Many species of butterfly lay their eggs off-host, rather than on the host plant. For example, the Silver-washed Fritillary (Argynnis paphia)oviposits on tree trunks above where Viola species are growing. Consequently, oviposition records need to be treated with caution, depending on the species.

What do butterfly larvae eat, and why does it matter?

Butterfly larvae can be very fussy about which plants they can use. 20% of European butterfly larvae are monophagous, feeding on just one species of plant. 50% are oligophagous, feeding on a few different closely related plants, whilst 30% are polyphagous feeding on plants in many different families. The Holy Blue (Celastrina argiolus) can utilise plants in an astonishing 19 different families.

The oligophagous butterflies can be divided into two groups:

Oligophagous-monophagous (OM) – feeding on one plant species in one region, and another species in another region.
Oligophagous-polyphagous (OP) – feeding on several closely related species of plants throughout their range, usually in the same genus, or a closely related genus.

4th instar Small Tortoiseshell feeding on Common Nettle.

Plant preferences are only known for a few species of butterflies. For example, the English race of the Swallowtail (Papilio machaon) feeds on Milk-parsley (Peucedanum palustre), whereas in the rest of Europe it has been recorded on 62 other plants. The main larval foodplant of the Small Tortoiseshell (Aglais urticae) is Common Nettle(Urtica dioica), although it will occasionally use other plants.

The survivability of larvae on different plants is largely unknown, except in a few cases where the butterfly species has been studied in detail. There are plants that larvae may be able to eat, but that would likely not help them survive to pupation.

Two species are known to switch their larval foodplant during their second year of development. The Scarce Fritillary (Euphydryas maturna),for example, switches from Ash (Fraxinus excelsior) to Guelder-rose (Viburnum opulus). The Northern Grizzled Skipper (Pyrgus centaureae) switches from Dwarf birch (Betula nana) to Cloudberry (Rubus chamaemorus).

The most delicious plants

For the first time, a list of the current accepted plant names utilised by 471 European butterfly larvae is presented, with references. Where possible, errors in previous lists have been removed. The list of larval foodplants doubled compared to previous published lists. This has resulted in a list of 1506 different plant species in 72 different families. 86 plant records are only known at the generic level. Larval foodplants of 25 butterfly species are currently unknown, which are mostly the “Browns” (Satyrinae), which probably feed on grasses (Poaceae), or possibly sedges (Cyperaceae).

Whilst most plant families are utilised by less than six butterfly species, a few plant families are particularly favoured, with grasses (Poaceae) and legumes (Fabaceae) being the most popular. Similarly, most plant species are only utilised by a few butterfly species, but the fine grasses Sheep’s Fescue (Festuca ovina) and Red Fescue (Festuca rubra) are favoured by a large number of butterfly species.

Taxonomic splits create problems. Where cryptic species are allopatric, records can be allocated on the basis of their distribution. But where cryptic species are sympatric, this will require a resurvey to determine the larval foodplants. It cannot be assumed that two cryptic butterfly species use the same plants, as something has to become different for them to evolve into separate species.

Looking forward

Future publications should ensure that old and ambiguous plant names are not used. Plant names should be specified with their full scientific name, as specified by the International Code of Nomenclature for algae, fungi, and plants. The World Checklist of Vascular Plants should be checked to ensure the currently accepted plant name is being used.

Fully documented records are needed of what larval foodplants butterfly larvae are utilising in the wild. To get a better understanding of usage, full details need to be recorded, including date, location, altitude, abundance, and larval stage. Abundance will help in the understanding of preferences. To allow records to be properly verified, evidence should be provided on how the larvae and plants were identified. Regional lists are also important – to help direct conservation efforts to the plants being used locally, rather than elsewhere. This list of larval foodplants is provided as a step towards a fully justified database, which will be updated as and when corrections are found. It highlights those 25 butterfly species whose larval foodplants are currently unknown.

4th instar Chequered Skipper (Carterocephalus palaemon) larvae feeding on Purple Moor-grass (Molinia caerulea).

Research article:

Clarke HE (2022) A provisional checklist of European butterfly larval foodplants. Nota Lepidopterologica 45: 139-167. https://doi.org/10.3897/nl.45.72017

Living room conservation: Gaming & virtual reality for insect and ecosystem conservation

Gaming and virtual reality could bridge the gap between urban societies and nature, thereby paving the way to insect conservation by the means of education and participation. This is what an interdisciplinary team at Florida International University strive to achieve by developing a virtual reality game (desktop version also available) dedicated to insect and plant species. Focused on imperiled butterflies, their innovative idea: Butterfly World 1.0, is described in the open-access journal Rethinking Ecology.

Participant playing the virtual reality version of Butterfly World 1.0.
Photo by Jaeson Clayborn.

Players explore and search for butterflies using knowledge gained through gameplay

Gaming and virtual reality (VR) could bridge the gap between urban societies and nature, thereby paving the way to insect conservation by the means of education, curiosity and life-like participation.

This is what Florida International University‘s team of computer scientist Alban Delamarre and biologist Dr Jaeson Clayborn strive to achieve by developing a VR game (desktop version also available) dedicated to insect and plant species. Focused on imperiled butterflies, their innovative idea: Butterfly World 1.0, is described in the open-access journal Rethinking Ecology.

When playing, information about each butterfly species is accessed on the player’s game tablet. Image by
Alban Delamarre and Dr Jaeson Clayborn.

Butterfly World 1.0 is an adventure game designed to engage its users in simulated exploration and education. Set in the subtropical dry forest of the Florida Keys (an archipelago situated off the southern coast of Florida, USA), Butterfly World draws the players into an immersive virtual environment where they learn about relationships between butterflies, plants, and invasive species. While exploring the set, they interact with and learn about the federally endangered Schaus’ swallowtail butterfly, the invasive graceful twig ant, native and exotic plants, and several other butterflies inhabiting the dry forest ecosystem. Other nature-related VR experiences, including conservation awareness and educational programs, rely on passive observations with minimal direct interactions between participants and the virtual environment.

According to the authors, virtual reality and serious gaming are “the new frontiers in environmental education” and “present a unique opportunity to interact with and learn about different species and ecosystems”.

In the real world, Spanish needles (Bidens alba) is considered a weed in South Florida. However, it is an excellent nectar source for butterflies.
Photo by Alban Delamarre.

The major advantage is that this type of interactive, computer-generated experience allows for people to observe phenomena otherwise impossible or difficult to witness, such as forest succession over long periods of time, rare butterflies in tropical dry forests, or the effects of invasive species against native wildlife.

“Imagine if, instead of opening a textbook, students could open their eyes to a virtual world. We live in a time where experiential learning and stories about different species matter, because how we feel about and connect with these species will determine their continued existence in the present and future. While technology cannot replace actual exposure to the environment, it can provide similar, near-realistic experiences when appropriately implemented,” say the scientists.

In conclusion, Delamarre and Clayborn note that the purpose of Butterfly World is to build knowledge, reawaken latent curiosity, and cultivate empathy for insect and ecosystem conservation.

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The game is accessible online at: http://ocelot.aul.fiu.edu/~adela177/ButterflyWorld/.

Original source:

Clayborn J, Delamarre A (2019) Living room conservation: a virtual way to engage participants in insect conservation. Rethinking Ecology 4: 31-43. https://doi.org/10.3897/rethinkingecology.4.32763

New butterfly species discovered in Russia with an unusual set of 46 chromosomes

What looked like a population of a common butterfly species turned out to be a whole new organism, and, moreover – one with a very peculiar genome organisation.

Discovered by Vladimir Lukhtanov, entomologist and evolutionary biologist at the Zoological Institute in St. Petersburg, Russia, and Alexander Dantchenko, entomologist and chemist at the Moscow State University, the startling discovery was named South-Russian blue (Polyommatus australorossicus). It was found flying over the northern slopes of the Caucasus mountains in southern Russia. The study is published in the open access journal Comparative Cytogenetics.

“This publication is the long-awaited completion of a twenty-year history,” says Vladimir Lukhtanov.

In the mid-nineties, Vladimir Lukhtanov, together with his students and collaborators, started an exhaustive study of Russian butterflies using an array of modern and traditional research techniques. In 1997, Alexander Dantchenko who was mostly focused on butterfly ecology, sampled a few blue butterfly specimens from northern slopes of the Caucasus mountains. These blues looked typical at first glance and were identified as Azerbaijani blue (Polyommatus aserbeidschanus).

However, when the scientists looked at them under a microscope, it became clear that they had 46 chromosomes – a very unusual number for this group of the blue butterflies and exactly the same count as in humans.

Having spent twenty years studying the chromosomes of more than a hundred blue butterfly species and sequencing DNA from all closely related species, the researchers were ready to ascertain the uniqueness of the discovered butterfly and its chromosome set.

Throughout the years of investigation, it has become clear that caterpillars of genetically related species in the studied butterfly group feed on different, but similar plants. This discovery enables entomologists to not only discover new butterfly species with the help of botanic information, but also protect them.

“We are proud of our research,” says Vladimir Lukhtanov. “It contributes greatly to both the study of biodiversity and understanding the mechanisms of biological evolution.”

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Original source:

Lukhtanov VA, Dantchenko AV (2017) A new butterfly species from south Russia revealed through chromosomal and molecular analysis of the Polyommatus (Agrodiaetus) damonides complex (Lepidoptera, Lycaenidae). Comparative Cytogenetics 11(4): 769-795. https://doi.org/10.3897/CompCytogen.v11i4.20072

Origins of an enigmatic genus of Asian butterflies carrying mythological names decoded

A group of rare Asian butterflies which have once inspired an association with Hindu mythological creatures have been quite a chaos for the experts. In fact, their systematics turned out so confusing that in order to decode their taxonomic placement, scientists had to dig up their roots some 43 million years back.

Now, having shed new light on their ancestors, a team of researchers from the Biodiversity Institute of Ontario at University of Guelph, Agriculture and Agri-Food Canada and University of Vienna, published their findings in the open access journal Zoosystematics and Evolution.

Together, Drs. Valentina Todisco, Vazrick Nazari and Paul Hebert arrived at the conclusion that the enigmatic genus (Calinaga) originated in southeast Tibet in the Eocene as a result of the immense geological and environmental impact caused by the collision between the Indian and Asian subcontinents. However, the diversification within the lineage was far from over at that point. In the following epochs, the butterflies had to adapt to major changes when Indochina drifted away, leading to the isolation of numerous populations; and then again, when the Pleistocene climatic changes took their own toll.

To make their conclusions, the scientists studied 51 specimens collected from a wide range of localities spanning across India, South China, Laos, Vietnam, Myanmar and Thailand. For the first time for the genus, the authors conducted molecular data and combined it with an examination of both genitalia and wing patterns – distinct morphological characters in butterflies. While previous estimates had reported existence of anywhere between one and eleven species in the genus, the present study identified only four, while confirming how easy it is to mislabel samples based on earlier descriptions.

However, the researchers note that they have not sampled specimens from all species listed throughout the years under the name of the genus, so they need additional data to confirm the actual number of valid Calinaga species. The authors are to enrich this preliminary study in the near future, analysing both a larger dataset and type specimens in collaboration with the Natural History Museum of London that holds the largest Calinaga collection.

Despite being beautiful butterflies, the examined species belong to a genus whose name derives from the Hindu mythical reptilian creatures Nāga and a particular one of them – Kaliya, which is believed to live in Yamuna river, Uttar Pradesh, and is notorious for its poison. According to the Hindu myths, no sooner than Kaliya was confronted by the major deity Krishna, did it surrender.

“It seems that the modern taxonomy of Calinaga is in need of a Krishna to conquer these superfluous names and cleanse its taxonomy albeit after careful examination of the types and sequencing of additional material,” comment the authors.

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Original source:

Todisco V, Nazari V, Hebert PDN (2017) Preliminary molecular phylogeny and biogeography of the monobasic subfamily Calinaginae (Lepidoptera, Nymphalidae). Zoosystematics and Evolution 93(2): 255-264. https://doi.org/10.3897/zse.93.10744

Gehry’s Biodiversity Museum – favorite attraction for the butterflies and moths in Panama

Ahead of Gehry’s Biodiversity Museum‘s opening in October 2014, PhD candidate Patricia Esther Corro Chang, Universidad de Panama, studied the butterflies and moths which had been attracted by the bright colours of the walls and which were visiting the grounds of the tourist site.

The resulting checklist, published in the open access journal Biodiversity Data Journal, aims to both evaluate the biodiversity and encourage the preservation and development of the Amador Causeway (Calzada de Amador) and the four Causeway Islands. The name of the islands derives from their being linked to each other and the mainland via a causeway made of rocks excavated during the construction of the Panama Canal.

The researcher reports a total of six butterfly and eight moth families, identified from the 326 specimens collected over the course of 10 months from the botanical garden of the museum and adjacent areas. They represent a total of 52 genera and 60 species.

Interestingly, the eye-catching bright colours of the walls of the museum seem to play an important role for the insect fauna of the area. Not only are numerous butterflies and moths being attracted to the site, but they also express curious behaviour. On various occasions, for example, a species of skipper butterfly was seen to show a clear preference for yellowish surfaces. In their turn, a number of butterfly predators, such as jumping spiders, are also frequenting the walls.

The article in the journal provides knowledge of the butterfly and moth fauna at the mainly vegetated study area, located on a narrow strip of water distant from the city of Panama.

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Original source:

Corro-Chang P (2017) Behavioural notes and attraction on Lepidoptera around the Gehry’s Biodiversity Museum (Causeway, Calzada de Amador, Panamá, República de Panamá). Biodiversity Data Journal 5: e11410. https://doi.org/10.3897/BDJ.5.e11410