“Trends in Arthropods of Alpine Aquatic Ecosystems” is the first topical collection for the journal of the Swiss Entomological Society
The open-access, peer-reviewed scholarly journal Alpine Entomology, published by Pensoft on behalf of the Swiss Entomological Society, announced its very first topical collection of articles, which will be focusing on arthropods associated with aquatic ecosystems in mountainous regions.
The journal is currently inviting scientists, working on aquatic fauna from alpine habitats, to openly publish their research articles and short notices that provide evidence how arthropods’ biogeography, species communities, distribution, behaviour and morphology have changed in recent times.
Revolutionary environmental DNA analysis holds great potential for the future of biodiversity monitoring, concludes a new study
In times of exacerbating biodiversity loss, reliable data on species occurrence are essential, in order for prompt and adequate conservation actions to be initiated. This is especially true for freshwater ecosystems, which are particularly vulnerable and threatened by anthropogenic impacts. Their ecological status has already been highlighted as a top priority by multiple national and international directives, such as the European Water Framework Directive.
However, traditional monitoring methods, such as electrofishing, trapping methods, or observation-based assessments, which are the current status-quo in fish monitoring, are often time- and cost-consuming. As a result, over the last decade, scientists progressively agree that we need a more comprehensive and holistic method to assess freshwater biodiversity.
Meanwhile, recent studies have continuously been demonstrating that eDNA metabarcoding analyses, where DNA traces found in the water are used to identify what organisms live there, is an efficient method to capture aquatic biodiversity in a fast, reliable, non-invasive and relatively low-cost manner. In such metabarcoding studies, scientists sample, collect and sequence DNA, so that they can compare it with existing databases and identify the source organisms.
Furthermore, as eDNA metabarcoding assessments use samples from water, often streams, located at the lowest point, one such sample usually contains not only traces of specimens that come into direct contact with water, for example, by swimming or drinking, but also collects traces of terrestrial species indirectly via rainfalls, snowmelt, groundwaters etc.
In standard fish eDNA metabarcoding assessments, these ‘bycatch data’ are typically left aside. Yet, from a viewpoint of a more holistic biodiversity monitoring, they hold immense potential to also detect the presence of terrestrial and semi-terrestrial species in the catchment.
In fact, it took only one day for the team, led by Till-Hendrik Macher, PhD student in the German Federal Environmental Agency-funded GeDNA project, to collect the samples. Using metabarcoding to analyse the DNA from the samples, the researchers identified as much as 50% of the fishes, 22% of the mammal species, and 7.4% of the breeding bird species in the region.
However, the team also concluded that while it would normally take only 10 litres of water to assess the aquatic and semi-terrestrial fauna, terrestrial species required significantly more sampling.
Unlocking data from the increasingly available fish eDNA metabarcoding information enables synergies among terrestrial and aquatic biodiversity monitoring programs, adding further important information on species diversity in space and time.
Macher T-H, Schütz R, Arle J, Beermann AJ, Koschorreck J, Leese F (2021) Beyond fish eDNA metabarcoding: Field replicates disproportionately improve the detection of stream associated vertebrate species. Metabarcoding and Metagenomics 5: e66557. https://doi.org/10.3897/mbmg.5.66557
Unidentified since its discovery in 2007, a large fish species from Amazonia has failed to give out enough information about itself, leaving only insufficient hints about its genus. Nevertheless, three scientists have now recovered the missing pieces to puzzle out its mysterious identity. In their study, published in the open-access journal ZooKeys, they describe the fish as a new species and name it after the fictional secretive Latin American character Zorro.
The new fish, called Myloplus zorroi, is commonly known among the Brazilians as ‘pacu’ and is a relative to the piranha. The research team, led by Marcelo C. Andrade, Universidade Federal do Para, Brazil, recognised in a fish, collected by sport fishermen from Rio Madeira basin, Brazil, a previously found, yet undescribed species. Following their analysis, it turned out that its discoverers had assumed an incorrect genus for it.
Among the distinctive features of the new fish, which helped its rightful placement, are its characteristic teeth, specialised to crush seeds.
The new pacu species is quite large, growing up to 47,5 cm. It dwells in moderately to rapidly flowing clear rivers, running over rocky or sandy bottoms, and ranging from about 2 to 8 metres in depth. Its basis colour is reddish silver with darker markings running along the upper side of the body. The head is dark and the belly – pale yellow.
Curiously enough, although the name of the new fish is chosen as a tribute to Mauricio Camargo-Zorro, a researcher at the Instituto Federal de Educacao, Ciencia e Tecnologia, in recognition of his invaluable contribution to the fish fauna inventory from the Marmelos Conservation Area, zorroi is also a playful reference to the Latin American fictional character Don Diego de la Vega and his secret identity hidden behind the nickname of Zorro.
Andrade MC, Jegu M, Giarrizzo T (2016) A new large species of Myloplus (Characiformes, Serrasalmidae) from the Rio Madeira basin, Brazil. ZooKeys 571: 153-167. doi: http://doi.org/10.3897/zookeys.571.5983.
A new weakly electric mormyrid fish genus of two new species has been described from only three specimens collected over a period of 13 years in the rivers of the Central African country of Gabon. The genus has been named Cryptomyrus, meaning ‘hidden fish’ in Greek, and is the first new genus to be described within the family Mormyridae since 1977.
The study, authored by Dr. John Sullivan and Prof. Carl Hopkins of Cornell University, Ithaca, New York, and Sebastien Lavoue of the Institute of Oceanography at the National Taiwan University in Taipei, Taiwan, is published in the open-access journal ZooKeys.
“It’s odd we have only three specimens, given how much fish collection effort there’s been in Gabon over the past years,” says lead author Dr. John Sullivan. “Not having more made the descriptions difficult, but it was important to bring this discovery to light without further delay.” Sullivan added that he does not know if these fish are rare throughout their range or if specialists simply have not sampled localities or habitats where they are common, yet. “It shows that we still have a very incomplete picture of fish diversity in Gabon,” says Dr. Sullivan.
The last of the three specimens was found on an expedition to Gabon’s Ogooue River in September 2014, jointly sponsored by CENAREST and The Nature Conservancy. It was after nightfall on the Ogooue, beside Doume Falls, when Sullivan and the other team members caught the one odd fish in a plastic fish trap baited with earthworms. Reflecting its river of origin, the species now bares the name Cryptomyrus ogoouensis, while the second – Cryptomyrus ona, is named after Gabonese environmental activist Marc Ona Essangui.
Puzzled over the identity of the fish, back home at the Cornell University Museum of Vertebrates Dr. Sullivan remembered two somewhat similar specimens collected in Gabon and sent to him for identification by his colleagues Sebastien Lavoue and Yves Fermon, 11 years apart. “This is why we need natural history collections,” said Dr. Sullivan, “to keep these specimens and their DNA samples in good condition, because it can take years or even decades to connect the dots.”
Analyses of the DNA from the three specimens conducted at Cornell University showed they were close relatives and did not belong within any recognized genus. “That left us no choice but to describe them as a new genus, and Cryptomyrus, which means “hidden fish,” seemed an appropriate name given how hard they are to find,” said Dr. Sullivan.
Over 200 species of mormyrid fish live in fresh waters across Africa where they orient to their environment and communicate using electric pulses, too weak to be felt by humans, in combination with highly sensitive electroreceptor cells embedded in their skin.
The Nature Conservancy, a global conservation organization that works in more than 35 countries around the world, funded the 2014 expedition of the Ogooue. “We were thrilled to have contributed to this discovery,” said Marie-Claire Paiz, Gabon Program Director for The Nature Conservancy. “Our goal is to help Gabon acquire better baseline knowledge about the state of their fish and rivers which will enable them make science-guided choices about where and how to use their resources wisely for both people and nature.”
“The Nature Conservancy deserves a lot of credit,” commented Sullivan. “It’s a great example of how a conservation organization can promote the discovery of biodiversity by partnering with taxonomists and natural history museums.”
Citation: Sullivan JP, Lavoue S, Hopkins CD (2016) Cryptomyrus: a new genus of Mormyridae (Teleostei, Osteoglossomorpha) with two new species from Gabon, West-Central Africa.ZooKeys 561: 117-150. doi: 10.3897/zookeys.561.7137