Santa Cruz de Tenerife, 31 Mar. (Europa Press) –
The scientific publication ‘Subterranean Biology’ has recently announced the identification of four new species of endemic underground chicharritas from the Canary Islands.
Specifically, these include ‘Cixius Palmirandus’ from La Palma, ‘Cixius beforeus’ and ‘Meenoplus Skotinophilus’ from El Hierro, along with Tachycixius gomerobscurus from La Gomera.
Globally, the existence of 70 species of chicharritas that have adapted to subterranean life has been documented to date.
With the addition of these four new species, the Canary Islands now host a total of 17 underground species of these insects, making it the region of the planet with the highest concentration of homoptera exhibiting this lifestyle, as noted by the CSIC.
The species ‘cixius analysis’ and ‘Tachycixius gomerobscurus’ were identified using a specially designed fall trap intended for exploring the underground habitat, created by researchers Heriberto López and Pedro Oromí.
This design evolved from previous models, refined until a prototype was published in 2010, which has successfully been employed in the Canary Islands and various global locations.
The other two species were discovered in volcanic caves; ‘Cixius Palmirandus’ was found in the Honda de Miranda cave in La Palma, while ‘Meenoplus Skotinophilus’ was located in a volcanic tube in Guinea on El Hierro, where they had not previously thrived.
The presence of these and other species with underground adaptations indicates the excellent conservation status of their subterranean habitat. Fauna that resides in the subsoil is highly susceptible to extinction when their habitat is contaminated or altered by human activities.
Chicharritas are small insects that belong to the homoptera group, typically living on plants, shrubs, and trees, where they feed on sap by piercing plant tissues with their needle-like mouthparts.
However, within the Canary Islands, two specific groups of chicharritas, known as cixids and menólidos, have adapted to thrive in the network of gaps and fissures present in underground environments or inside volcanic caves, which is the habitat of the four newly identified species.
In this setting, they also consume sap from plants but do so by extracting it from the roots found underground.
To survive in subterranean ecosystems, these species have undergone a series of characteristic adaptations typical of underground fauna: they are either blind or have significantly reduced eyesight, their wings have diminished or become non-functional, and their bodies exhibit slight depigmentation.
Vulnerable Species
Each of these new species has a restricted distribution, being limited to a single locality, with only a small number of individuals known for each. Consequently, these are rare species with few specimens in their habitats.
This situation renders them highly vulnerable insects to any catastrophe that could adversely affect their distribution, potentially leading to extinction if the event is severe. As such, the scientific team has suggested classifying the conservation status of these new chicharritas as vulnerable, based on criteria set by the IUCN, the International Union for the Conservation of Nature.
The scientific team responsible for this study also explores the origins of the remarkable diversity of underground homoptera in the Canary Islands.
Currently, no living species have been identified abroad from which these Chicharritas of the Canary Islands adapted to underground environments may have descended, suggesting they may have diverged over thousands of years of evolutionary history.
Therefore, genetic studies are being conducted at the IPNA-CSIC to clarify this uncertainty, attempting to determine whether the ancestors of these species were any of those present in non-underground habitats on the islands, or if they are relatives of those found in continental regions.
The ongoing discoveries of underground chicharritas in the Canary Islands over recent decades imply that numerous additional species of this type of homoptera are yet to be discovered.
The research has been led by Hannelore Hoch from the Museum of Natural Sciences in Berlin, collaborating with researchers from the Canary Islands and Madeira.
The Canary Islands scientific team comprises Heriberto López from the Institute of Natural Products and Agrobiology of the CSIC (IPNA-CSIC), Pedro Oromí from the University of La Laguna (ULL), and Manuel Naranjo from the Melansis Entomology Group.
From the University of Madeira, Dora Aguín, a specialist in this group of insects, has also contributed to this research.
