Mediterranean

Flamboyant and lethal: unveiling the lionfish invasion of the Mediterranean Sea

So-called ‘devil firefish’ are taking over new waters with little resistance from native species.

Research from Wageningen University a n d Research, the Netherlands, reveals invasive lionfish are rapidly expanding their territory in the Mediterranean sea, causing severe ecological damage.

Published in the open-access journal NeoBiota, the study shows the lionfish species Pterois miles – known as the devil firefish – has established presence in the eastern Mediterranean, with observations now extending to colder waters previously thought to be unsuitable for the species.

A map of the Mediterranean Sea, with dots showing the first sighting of invasive lionfish. It shows a gradual eastwrd progression of lionfish sightings over time. — Map of years of first sighting of *Pterois miles* by dive centres. Credit: Bottacini et al.

Originating from the Indo-Pacific region, the lionfish species Pterois miles and Pterois volitans are regarded as the most successful and lethal invasive fishes in marine ecosystems, with the capacity to drastically affect local fish communities and biodiversity in invaded areas.

The invasion of Pterois miles in the Mediterranean Sea began around ten years ago. Genetic studies reveal the invasive fish originated from the Red Sea and likely entered through the Suez Canal.

The beautiful but deadly devil firefish. Credit: Kora27 via Wikimedia Commons.

Lionfish are generalist predators and impact ecosystems by preying extensively on local fishes, including endemics of high conservation value. As they are unaccustomed to lionfish, native prey species usually do not flee from this new predator.

“After years studying these predators, I find it amazing how they can easily adjust to so many different environments and be successful in areas so different from where they evolve.”

“It is always impressive to see how such a flamboyant and–to us–conspicuous predator can approach its prey without being noticed”
The study’s lead author, Davide Bottacini.

The fin spines of Pterois miles are highly venomous. A sting can cause extreme pain, sickness, convulsions, minor paralysis, and breathing difficulties in humans. Immediate emergency medical attention is recommended for anyone stung by the species.

By reviewing existing scientific data, researchers identified gaps in current understanding of the lionfish’s interactions with Mediterranean ecosystems.

They suggest that, while they consider the eradication of invasive lionfish impossible, tackling questions such as the community-level impact of them in the Mediterranean, and the evolutionary and learned responses in prey, will add to the body of knowledge on the best documented invasion in marine ecosystems.

Three maps of dive centre respondents and lionfish sightings on the Meditteranean Sea coat showing a gradual eastwrd progression of sightings. — Maps of dive centre respondents and lionfish sightings. Credit: Bottacini et al.

Such information provides insights vital for biodiversity conservation, with practical implications for policy makers aiming to devise efficient mitigation plans.

Citizen science initiatives for tracking and reporting lionfish sightings are encouraged to provide valuable data that supports ongoing research efforts. Such community involvement is essential for enhancing understanding of the invasion dynamics and devising effective control measures.

Original source

Bottacini D, Pollux BJA, Nijland R, Jansen PA, Naguib M, Kotrschal A (2024) Lionfish (Pterois miles) in the Mediterranean Sea: a review of the available knowledge with an update on the invasion front. NeoBiota 92: 233–257. https://doi.org/10.3897/neobiota.92.110442

Follow NeoBiota on X and Facebook.

Lifting the veil over mysterious desert truffles: Terfezia’s ecology and diversity towards cultivation

Developing below the soil surface, desert truffles are hard to find. Recently, researchers of the University of Évora updated the number of known species of the desert truffle genus Terfezia occurring in Portugal from three to ten species. They thoroughly characterized their ecological preferences, adding new knowledge on Terfezia’s cryptic lifestyle. These findings are of major importance, as desert truffles have a high economic value. The study was published in the open-access journal MycoKeys.

In a caring, symbiotic relationship, mycorrhizal fungi live and feed in the roots of specific plants, while providing water and nutrients to their ‘companion’. In arid and semi-arid environments, mycorrhization processes are essential to the survival of both plants and fungi. Moreover, the fungus’ hyphal network, which spreads within the soil connecting several plant individuals, is of utmost importance to enhancing soil quality and fertility.

Researchers of the University of Évora in Portugal, led by biologist Celeste Santos e Silva, worked on Terfezia fungi, the most diverse and species-rich genus among desert truffles. Their study, published in the open-access journal MycoKeys, might prove particularly valuable to rural populations in the Mediterranean basin, where desert truffles, highly valued in local markets, are an important food source. Increasingly turning into an exquisite component of the Mediterranean diet, Terfezia products can also be very profitable. Furthermore, these fungi are essential for soil conservation, preventing erosion and desertification.

After 8 years of exhaustive field exploration in search of desert truffles and many hours in the molecular biology lab, the researchers noted some previously unknown trends in the ecology of Terfezia species. They recorded seven species that were new to Portugal, including two that are new to science – Terfezia lusitanica and Terfezia solaris-libera. This brings the number of Terfezia species known to be growing in the country to ten. Particularly important was the discovery of a broader ecological range for many of the studied species (e.g. Terfezia grisea). Adding valuable information about their possible hosts, symbionts and ecological constraints, these findings help open new opportunities for truffle cultivation.

“It is very difficult to identify all specimens given that the Terfezia species look so much alike, and molecular biology was absolutely fundamental here”, explains the researcher. “The technique was essential to update and solve problems about their taxonomy and the relationship between the species in the genus.”

Furthermore, the discoveries are also expected to positively impact the local communities by stimulating agriculture produce, business and even employment.

Desert truffle production explained. Video by University of Évora

Knowledge gained in this research about the conditions in which different Terfezia species grow is an important step to desert truffle cultivation: the fungi are hard to find in the wild, which is why it would make a big difference – including financially – for local communities if they figure out a way to grow truffles themselves.

Within the project “Mycorrhization of Cistus spp with Terfezia arenaria (Moris) Trappe and its application in the production of desert truffles” (ALT20-03-0145-FEDER-000006), the researchers took a step forward towards achieving mycorrhizal association of desert truffles with perennial plants (rock roses), which would allow their mass production for various sectors such as food, medicine and soil recovery. This new form of production, assures the MED researcher and leader of the project, “will make it possible to create more jobs, reversing the current trend towards desertification in rural areas, while being a great tool for ecosystem recovery and restoration”.

Research article:

Santos-Silva C, Louro R, Natário B, Nobre T (2021) Lack of knowledge on ecological determinants and cryptic lifestyles hinder our understanding of Terfezia diversity. MycoKeys 84: 1-14. https://doi.org/10.3897/mycokeys.84.71372

Scientists dive into museum collections to reveal the invasion route of a small crustacean

Biological invasions are widely recognised as one of the most significant components of global change. Far-reaching and fast-spreading, they often have harmful effects on biodiversity.

Therefore, acquiring knowledge of potentially invasive non-native species is crucial in current research. In particular, it is important that we enhance our understanding of the impact of such invasions.

To do so, Prof Sabrina Lo Brutto and Dr Davide Iaciofano, both working at the Taxonomy Laboratory of the University of Palermo, Italy, performed research on an invasive alien crustacean (Ptilohyale littoralis) known to have colonised the Atlantic European Coast. Their findings are published in the open access journal ZooKeys.

The studied species belongs to a group of small-sized crustaceans known as amphipods. These creatures range from 1 to 340 mm in length and feed on available organic matter, such as dead animals and plants. Being widely distributed across aquatic environments, amphipods have already been proven as excellent indicators of ecosystem health.

While notable for their adaptability and ecological plasticity, which secure their abundance in various habitats, these features also make amphipods especially dangerous when it comes to playing the role of invaders.

Having analysed specimens stored at the Museum of Natural History of Verona and the Natural History Museum in Paris, the scientists concluded that the species has colonised European waters 24 years prior to the currently available records.

The problem was that, back in 1985, when the amphipod was first collected from European coasts, it was misidentified as a species new to science instead of an invader native to the North American Atlantic coast.

A closer look into misidentified specimens stored in museum collections revealed that the species has been successfully spreading along the European coastlines.

Male of the invasive amphipod species (*Ptilohyale littoralis*), sampled in October 2015, from Bay of Arcachon, France.

Moreover, it was predicted that the amphipod could soon reach the Mediterranean due to the high connectivity between the sea and the eastern Atlantic Ocean through the Straits of Gibraltar – a route already used by invasive marine fauna in the past.

In the event that the invader reaches the Mediterranean, it is highly likely for the crustacean to meet and compete with a closely related “sister species” endemic to the region. To make matters worse, the two amphipods are difficult to distinguish due to their appearance and behaviour both being extremely similar.

However, in their paper, the scientists have also provided additional information on how to distinguish the two amphipods – knowledge which could be essential for the management of the invader and its further spread.

The authors believe that their study demonstrates the importance of taxonomy – the study of organism classification – and the role of natural history collections and museums.

“Studying and monitoring biodiversity can acquire great importance in European aquatic ecosystems and coastal Mediterranean areas, where biodiversity is changing due to climate change and invasions of alien species,” Prof Lo Brutto says. “In this context, specific animal groups play a crucial role in detecting such changes and they, therefore, deserve more attention as fundamental tools in biodiversity monitoring.”

“Regrettably, the steadily diminishing pool of experts capable of accurately identifying species poses a serious threat in this field.”

###

Original source:

Lo Brutto S, Iaciofano D (2018) A taxonomic revision helps to clarify differences between the Atlantic invasive Ptilohyale littoralis and the Mediterranean endemic Parhyale plumicornis(Crustacea: Amphipoda). ZooKeys, 754: 47-62. https://doi.org/10.3897/zookeys.754.22884