A double defensive mutualism? A case between plants, extrafloral nectaries, and trophobionts

Тhis is the first case reported in the literature of a double defensive mutualism occurring simultaneously on a single plant species.

Guest blog post by Cássio Pereira

The Zeyheria montana shrub is quite common in the Brazilian Cerrado and is known to have extrafloral nectaries on the leaf blade that attract patrolling ants such as the aggressive Ectatomma tuberculatum. The ant, in turn, defends the leaves against the action of herbivores. However, extrafloral nectaries can distract ants on the leaves, segregating them from the reproductive parts and preventing them from driving away pollinators, which can benefit the action of florivores and nectar robbers.

Surprisingly, in southeastern Brazil, we observed a second defensive mutualism occurring on the reproductive tissues of these shrubs between E. tuberculatum and the treehopper Guayaquila xiphias, which provides the ant with honeydew in exchange for protection. This trophobiosis relationship (interaction between ants and phytophagous hemipterans that secrete sugary exudates) seems to be effective not only in the defense of floral buds and flowers, but also of the fruit, which, despite being dry, contains a lot of water in its formation and is attacked by beetles of the Curculionidae family.

The treehoppers G. xiphias at the base of Z. montana fruits.

As far as we know, this is the first case reported in the literature of a double defensive mutualism occurring simultaneously on a single plant species. Given this record, important questions arise regarding these interactions. Is the trophobiosis that occurs in reproductive organs capable of increasing the fitness of these plants? Although these ants are probably also scaring away possible pollinating insects, could the fact that Z. montana is primarily pollinated by hummingbirds offset this loss given that hummingbirds are larger and perhaps immune to ant attacks?

Our record raises more questions than it answers. Long-term Z. montana population studies would help improve our ecological understanding of these interactions.

New subspecies of the rarest Palaearctic butterfly found in the Arctic Circle of Yakutia

An isolated population of the rarest Palaearctic butterfly species: the Arctic Apollo (Parnassius arcticus), turned out to be a new to science subspecies with distinct looks as well as DNA. Named Parnassius arcticus arbugaevi, the butterfly is described in a recent paper, published in the peer-reviewed, open-access scientific journal Acta Biologica Sibirica

“Thanks to the field studies of our colleague and friend Yuri Bakhaev, we obtained unique butterfly specimens from the Momsky Range in North-Eastern Yakutia. This mountain range, which is about 500 km long, has until now been a real ‘blank spot’ in terms of biodiversity research,”

explains the lead author of the study, Dr Roman Yakovlev, affiliated with Tomsk State University and Altai State University.

“With the kind permission of Mikhail Ivanov, Director of the Momsky National Park, entomological collections were carried out in various parts of the park. Hard-to-reach areas were visited with the help of inspector Innokenty Fedorov,”

he adds.

Then, amongst the specimens, the scientists spotted butterflies that at first they thought to be the rarest species for the entire Palaearctic: the Arctic Apollo, a species endemic to Russia and North-Eastern Yakutia, which had only been known from the Suntar-Khayata and Verkhoyansk mountains. 

Later, however, the team noticed that the curious specimens were larger on average, had more elongated wings compared to the Arctic Apollo, and were also missing the distinct dark spot on the wings. At that moment, they thought they were rather looking at a species currently unknown to science, and belonging to the Parnassius tenedius species group.

Eventually, following in-depth morphological and molecular genetic analyses, the scientists concluded that the population from the Momsky Range was in fact a new subspecies of the Arctic Apollo and can be distinguished by a number of external and DNA differences. They named the new subspecies Parnassius arcticus arbugaevi after German Arbugaev, Director of the ecological-ethnographic complex Chochur Muran, who provided comprehensive assistance to one of the co-authors of the study, Yu.I. Bakhaev, in his research in Yakutia. 

The new subspecies inhabits dry scree slopes with poor vegetation at an elevation of 1,400 m. So far, it is only known from the type locality, Momsky Range, North-Eastern Yakutia, where butterflies can be seen from early June to July. The wingspan in males range between 39 and 45 mm.

“Thus, we obtained significant new data on the distribution and taxonomy of one of the rarest butterflies in the North Palaearctic,”

say the researchers in conclusion.

Original source:

Yakovlev RV, Shapoval NA, Bakhaev YI, Kuftina GN, Khramov BA (2020) A new subspecies of Parnassius arcticus (Eisner, 1968) (Lepidoptera, Papilionidae) from the Momsky Range (Yakutia, Russia). Acta Biologica Sibirica 6: 93-105. https://doi.org/10.3897/abs.6.e55925

New species of moths discovered in the Alps named after three famous alpinists

David Lama (1990 – 2019), a legendary alpinist, recognised by the study’s author also for his commitment to conservation.
Photo by MoserB / Copyrighted free use

The discovery of new, still unnamed animal species in a well-researched European region like the Alps is always a small sensation. All the more surprising is the description of a total of three new to science species previously misidentified as long-known alpine moths.

During a genetic project of the Tyrolean State Museums in Innsbruck (Austria), Austrian entomologist and head of the Natural Science Collections Peter Huemer used an integrative research approach that relies on molecular methods to study four European moths. Despite having been known for decades, those species remained quite controversial, because of many unknowns around their biology.

At the end, however, it turned out that the scientist was not dealing with four, but seven species. The three that were not adding up were indeed previously unknown species. Therefore, Huemer described the moths in a paper in the open-access, peer-reviewed journal Alpine Entomology. Curiously, all three species were given the names of legendary alpinists: Reinhold Messner, Peter Habeler and David Lama.

Habitat of Caryocolum lamai (Lama’s Curved-horn moth), Italy, Alpi Cozie, Colle Valcavera.
Photo by Peter Huemer

Tribute to three legends in alpinism

“The idea to name the new species in honour of three world-renowned climbers was absolutely no coincidence,”

explains Huemer.

One of the newly described species, Caryocolum messneri, or Messner’s Curved-horn moth, is dedicated to Reinhold Messner. Messner is a famous alpinist who was the first to reach Mount Everest without additional oxygen, but also the first climber to ascend all fourteen peaks over 8,000 metres. For decades, he has been inspiring followers through lectures and books. His is also the Messner Mountain Museum project, which comprises six museums located at six different locations in South Tyrol, northern Italy, where each has the task to educate visitors on “man’s encounter with mountains” by showcasing the science of mountains and glaciers, the history of mountaineering and rock climbing, the history of mythical mountains, and the history of mountain-dwelling people.

“So what could have been a better fit for a name for the species that flutters on the doorstep of his residence, the Juval Castle in South Tyrol?”

says Huemer.

The second new species, Caryocolum habeleri, or Habeler’s Curved-horn moth, honours another extraordinary mountaineer: Peter Habeler. Having joined Messner on his expedition to Mount Everest, he also climbed this mountain without additional oxygen in a first for history. Another achievement is his climbing the famous Eiger North Face in mere 10 hours. Additionally, together with the study’s author, he sits on the advisory board of the nature conservation foundation “Blühendes Österreich“. However, the species’ name is also a nod to Peter Habeler’s cousin: Heinz Habeler, recognised as “the master of butterfly and moth research in Styria”. His collection is now housed in the Tyrolean State Museums.

The third alpinist, whose name is immortalised in a species name, is David Lama, specially recognised by Huemer for his commitment to conservation. Once, in order to protect endangered butterflies along the steep railway embankments in Innsbruck, Lama took care to secure volunteers in a remarkable action. Nevertheless, Lama earned his fame for his spectacular climbing achievements. His was the first free ascent of the Compressor route on the south-eastern flank of Cerro Torre.

“Unfortunately, David lost his life far too soon in a tragic avalanche accident on 16 April 2019 in Banff National Park, Canada. Now, Caryocolum lamai (Lama’s Curved-horn moth) is supposed to make him ‘immortal’ also in the natural sciences,”

says Huemer.

Many unresolved questions

The newly described moth species are closely related and belong to the genus Caryocolum of the so-called Curved-horn moths (family Gelechiidae).

A Curved-horn moth of the genus Caryocolum feeding on a carnation plant. This genus feeds exclusively on plants in the carnation family (Caryophyllaceae).
Photo by P. Buchner / Tiroler Landesmuseen

As caterpillars, the species of this genus live exclusively on carnation plants. Even though the biology of the new moths is still unknown, because of their collection localities, it could be deduced that plants such as the stone carnation are likely their hosts. All species are restricted to dry and sunny habitats and sometimes inhabit altitudes of up to 2,500 m. So far, they have only been observed with artificial light at night.

While Messner’s Curved-horn moth occurs from northern Italy to Greece, the area of Habeler’s Curved-horn Moth is limited to the regions between southern France, northern Switzerland and southeastern Germany. On the other hand, Caryocolum lamai, only inhabits a small area in the western Alps of Italy and France.

Research on alpine butterflies and moths has been an important scientific focus at the Tyrolean state museums for decades. In 30 years, Peter Huemer discovered and named over 100 previously unknown to science species of lepidopterans. All these new discoveries have repeatedly shown the gaps in the study of biodiversity, even in Central Europe.

“How could we possibly protect a species that we don’t even have a name for is one of the key questions for science that derives from these studies,”

says Huemer in conclusion.

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Original source:

Huemer P (2020) Integrative revision of the Caryocolum schleichi species group – a striking example of a temporally changing species concept (Lepidoptera, Gelechiidae). Alpine Entomology 4: 39-63. https://doi.org/10.3897/alpento.4.50703

New to science New Zealand moths link mythological deities to James Cameron’s films

In an unexpected discovery from New Zealand, two species of narrowly distributed moths were described as new species. Interestingly, both Arctesthes titanica and Arctesthes avatar were named after mythological deities and top-grossing blockbusters by famous filmmaker James Cameron: Titanic and Avatar, respectively.


The newly described moth species Arctesthes avatar in its natural habitat (South Island, New Zealand). Photo by Brian Patrick.

In an unexpected discovery from the South Island (New Zealand), two species of narrowly distributed macro-moths were described as new species. Interestingly, both Arctesthes titanica and Arctesthes avatar were named after mythological deities and top-grossing blockbusters by famous filmmaker James Cameron: Titanic and Avatar, respectively.

Each of the newly described species are believed to be restricted to only a couple of subalpine/alpine localities. Therefore, they are particularly vulnerable to extinction and need to be “considered of very high priority for conservation”, point out New Zealand scientists Brian Patrick (Wildland Consultants Ltd), Hamish Patrick (Lincoln University) and Dr Robert Hoare (Manaaki Whenua-Landcare Researchin their paper in the open-access journal Alpine Entomology.


Male (left) and female (right) specimens of the newly described moth species Arctesthes titanica. Photo by Birgit Rhode.

Because of its relatively large size, one of the new discoveries: A. titanica, was named in reference to the Titans: the elderly gods in Greek mythology and the legendary, if ill-fated, record-breaking passenger ship ‘Titanic’, which became the subject of the famous 1997 American epic romance and disaster film of the same name. Unfortunately, the moth’s small wetland habitat is located in an area that is currently facing a range of damaging farming practices, such as over-sowing, grazing, stock trampling and vehicle damage.

On the other hand, A. avatar received its name after Forest & Bird, the New Zealand conservation organisation that was behind the 2012 BioBlitz at which the new species was collected, ran a public competition where “the avatar moth” turned up as the winning entry. The reference is to the indigenous people and fauna in Avatar. Just like them, the newly described moth is especially vulnerable to habitat change and destruction. In addition, the study’s authors note that the original avatars came from Hindu mythology, where they are the incarnations of deities, including Vishnu, for example, who would transform into Varaha the boar.

In conclusion, the scientists point out that future studies to monitor and further understand the fauna of New Zealand are of crucial importance for its preservation:

“Quantitative studies as well as work on life histories and ecology are particularly needed. Already one formerly common endemic geometrid species, Xanthorhoe bulbulata, has declined drastically and is feared possibly extinct: its life history and host-plant have never been discovered. Without further intensive study of the fauna of modified and threatened New Zealand environments, we will be unable to prevent other species slipping away.”

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Original source:

Patrick BH, Patrick HJH, Hoare RJB (2019) Review of the endemic New Zealand genus Arctesthes Meyrick (Lepidoptera, Geometridae, Larentiinae), with descriptions of two new range-restricted species. Alpine Entomology 3: 121-136. https://doi.org/10.3897/alpento.3.33944