Beneath the lush rainforests of the Yucatan Peninsula lies a hidden, subterranean world: a vast network of flooded sinkholes and anchialine caves. These unique underwater systems, which mix fresh and saltwater and are influenced by the tides, have no open connection to the surface and have served as an evolutionary refuge for millions of years.
When marine biologist Fernando Álvarez first encountered these sinkholes (cenotes), he was captivated.
My first impression of these incredibly beautiful places was that I had to work there to find out how that rich crustacean fauna had evolved in those exceptionally large cave systems.
Álvarez recalls
Entrance to a cenote. Photo credit to Fernando Álvarez.
Entrance to a cenote. Photo credit to Fernando Álvarez.
The cenotes where Typhlatya shrimps occur. Photo credit to Fernando Álvarez.
A recent study published in Subterranean Biology, reveals that the answer lies with a tiny, fascinating creature: the anchialine cave shrimp of the genus Typhlatya.
The Keystone of the Cave Food Web
The cenotes where Typhlatya shrimps occur. Photo credit to Fernando Álvarez.
In most surface ecosystems, sunlight fuels plants, which then feed the rest of the food chain. In the pitch-black depths of anchialine caves, nature has found other ways. Instead of photosynthesis, this ecosystem relies on a chemosynthetic route.
Organic matter from the rainforest floor decomposes and percolates through the porous limestone rock, eventually bringing methane into the cave’s waters. Methanotrophic bacteria consume this methane to produce energy and grow. And this is where Typhlatya shrimp comes in. Equipped with specialized, scraping appendages, these shrimps are adapted to graze on these bacterial mats.
Because they convert microbial growth into animal biomass, Typhlatya shrimps act as “keystone species,” introducing essential nutrients into the cave’s food web. They serve as a crucial initial link that larger subterranean predators feed on.
What we see now is that Typhlatya shrimps are a key component of the anchialine trophic web.
explains Álvarez
Stable Isotopes reveal ecological niches
To better understand how these shrimps survive, Brenda Durán and Fernando Álvarez used stable isotope analysis (looking at carbon and nitrogen signatures in the shrimps’ tissue) to figure out exactly what they are eating.
Typhlatya mitchelli. Photo credit to Fernando Álvarez.
Typhlatya mitchelli. Photo credit to Fernando Álvarez.
Over the years my research has evolved from very descriptive taxonomic studies… to more ecological studies about the interactions among species.
Álvarez notes regarding the motivation behind the study.
Their findings revealed that the different species of Typhlatya living in the Yucatan have carved out their own unique dietary niches, allowing them to peacefully coexist.
For instance, Typhlatya mitchelli relies mostly on decaying vegetation and nitrifying bacteria found in shallower cave sections. While, Typhlatya dzilamensis hangs out deeper in the caves near the halocline (the zone where fresh and saltwater mix), exploiting organic material trapped in that layer. Typhlatya pearsei feeds heavily on the methanotrophic bacterial biomass near the cave ceilings.
Beneath the lush rainforests of the Yucatan Peninsula lies a hidden, subterranean world: “My first impression of these incredibly beautiful places was that I had to work there to find out how that rich crustacean fauna had evolved in those exceptionally large cave systems.” – Marine biologist Fernando Álvarez. 👇 A reminder to check out our blog here for further insights: https://blog.pensoft.net/?p=18058 👇 Full article in the open-access journal Subterranean Biology: https://doi.org/10.3897/subtbiol.55.164068 #shrimp#yucatan#sciencenews#subterranean#ecology
Interestingly, the study found that the shrimps’ diets remain stable across the rainy and dry seasons. However, their diets do shift based on regional geography, such as the difference between the deep, isolated sinkholes of the “Ring of Cenotes” and the sprawling, highly interconnected tunnels of the “Caribbean Cave Area”.
A Fragile World Under Threat
The cenotes where Typhlatya shrimps occur. Photo credit to Fernando Álvarez.
These remarkable cave shrimps belong to an ancient lineage that has survived since the time of the dinosaurs, with relatives spanning the globe from the Mediterranean to Australia. Yet, they are now facing a modern, unprecedented threat.
The rapid urbanization of the Yucatan Peninsula brings deforestation, pollution, and severe environmental deterioration. Because these caves rely entirely on the organic matter percolating from the rainforest above, any damage to the surface environment directly destroys the “vertical integrity” necessary for the caves to function. As Álvarez warns:
We are losing the vertical integrity that these anchialine caves need to function; any changes occurring on the surface within the caves’ area will inevitably affect them.
The anchialine caves of the Yucatan Peninsula are complex, unique ecosystems filled with extraordinary biodiversity. To save the remarkable Typhlatya shrimp and the hidden food web it supports, we must protect the forests above ground.
Blind eel in an anchialine cave. Video credit to Fernando Álvarez.
The Yucatan Peninsula is an area of extraordinary cultural wealth and contains sophisticated and unique ecosystems as the anchialine caves, but sadly all this is disappearing.
he reflects
After all, the survival of this dark, subterranean world depends entirely on the health of the sunlit world above.
Original study
Durán B, Álvarez F (2026) The trophic role of cave shrimps of the genus Typhlatya seen through stable isotope eyes. Subterranean Biology 55: 43-56. https://doi.org/10.3897/subtbiol.55.164068
What is now celebrated globally as Taxonomist Appreciation Day began in 2013. 19 March was declared by Dr. Terry McGlynn – a researcher and professor at California State University, Dominguez Hills – as a new holiday to highlight the extraordinary importance of taxonomy and taxonomist scientists to research in other fields.
Last year saw fascinating discoveries in the world of marine life. And today, we are super excited to share with you the species that made it to the Top 10 this year, first published in Pensoft’s open-access journal ZooKeys.
How are these lists compiled? It is a rigorous process, where WoRMS first invites all their editors to nominate their favourites, and then asks a small committee of taxonomists and data managers to provide their votes.
Now, without further ado, join us into the Dark Side to find out exactly why and how this particular species turned up at the top.
The Supergiant Isopod
The head of Bathynomus vaderi. Image by Nguyen Thanh Son
Meet Bathynomus vaderi, a supergiant isopod belonging to the genus Bathynomus. Species from this genus can reach more than 30 cm in length and are known in Vietnam as bọ biển or “sea bugs.” Bathynomus vaderi marks the first record of such a species in Vietnamese waters.
As you might have guessed, the moniker vaderi is inspired by the appearance of its head, which closely resembles the distinctive and iconic helmet of Darth Vader, the most famous character of Star Wars.
From the Market to the Lab
Prof. Peter Ng examining giant isopods from a seafood market in Hanoi, October 2024. Photo by Nguyen Thanh Son
Dr. Conni Sidabalok examining individuals of Bathynomus vaderi at Lee Kong Chian Natural History Museum, Singapore. Photo by Rene Ong
The story of how it was found is quite compelling. In contrast to the traditional image of deep-sea expeditions, Bathynomus vaderi was obtained from local sellers where the isopods are fished.
In March 2022, staff from Hanoi University purchased four giant isopod individuals from Quy Nhơn City and sent two of them to Peter Ng from the National University of Singapore for identification. Subsequently, this sparked an international collaboration between Ng, Conni M. Sidabalok (National Research and Innovation Agency, Indonesia), and Nguyen Thanh Son (Vietnam National University). Together, this expert team studied the specimens and confirmed they had discovered a species new to science.
Video by Kyle Hill on YouTube.
A Deep-Sea Delicacy
Giant isopods like Bathynomus vaderi have become an expensive delicacy in Vietnam. Until 2017, local fishermen only sold them as low-priced bycatch, but in recent years, the media has drawn public attention to this unusual seafood. Some even claim it is more delicious than lobster, the “king of seafood.”
The Importance of the Find
News story by Margherita Bassi via the Smithsonian magazine.
This discovery is a reminder of just how much we still don’t know about the vast deep-sea environment. If such a supergiant isopod could remain hidden for so long, it speaks to the extraordinary amount of work still needed to uncover the rich biodiversity of Southeast Asian waters – work that depends on the combined efforts of researchers and taxonomists, whose contributions are at the frontline of conservation.
The celebration is not over; we invite you to explore the Pensoft-published species that have previously made it to the WoRMS Top 10 and revisit the ocean’s most fascinating discoveries:
Ng PKL, Sidabalok CM, Nguyen TS (2025) A new species of supergiant Bathynomus A. Milne-Edwards, 1879 (Crustacea, Isopoda, Cirolanidae) from Vietnam, with notes on the taxonomy of Bathynomus jamesi Kou, Chen & Li, 2017. ZooKeys 1223: 289-310. https://doi.org/10.3897/zookeys.1223.139335
Scientists compiled and summarized the largest dataset to date on the cladocerans of the Republic of Tyva—the result of almost thirty years of field work.
Guest blog post by Nadezhda Kirova, Valeria Kirova, Alexey Kotov and Dr. Petr Garibian
The functioning of freshwater ecosystems is impossible without cladocerans (water fleas), which play a key role in the food chains of most continental water bodies. Although the cladoceran fauna is relatively well-studied in the Palearctic as a whole, vast territories of Central Asia, including the Republic of Tyva, have until recently been only fragmentarily studied and required systematic survey.
Different zooplankton in a Petri dish. Photo by Dr.Petr Garibian
The first mentions of water bodies in Tyva date back to the 16th century, with the first data on zooplankton appearing in the early 20th century in the works of the Norwegian researcher Georg Ossian Sars (1903) and the Soviet scientist Vyacheslav Rylov (1923, 1930). Historical events of the 20th century significantly influenced the development of hydrobiological research in the region: after the republic became part of the USSR in 1944, the study of water bodies was actively conducted within the framework of ichthyological and fisheries tasks.
Starting from the 1960s, under the leadership of Tomsk scientists Alexey Gundrizer and later Victor Popkov, large-scale ichthyological and hydrobiological research was carried out in the region. During this period, zooplankton was studied primarily as a food source.
Cladocerans — the invisible foundation of freshwater life
Daphnia galeata is a small species of planktonic crustaceans. Photo taken by Dr.Petr Garibian
If you were to scoop up water from any lake, pond, or steppe salt marsh and examine it under a microscope, you would almost certainly see cladocerans among the first creatures—microscopic crustaceans, usually 0.2–6 mm in size, invisible to the naked eye, but playing a huge role in freshwater ecosystems.
What are they?
Cladocerans are small crustaceans with a characteristic rounded or oval body shape; in most species, the limbs are hidden behind paired valves or a carapace. Externally, they may resemble miniature droplets pulsating in the water. The most well-known representatives of cladocerans are from the genus Daphnia. When first discovered, they were called “pulex aquaticus” or “water flea,” a term still used in scientific publications.
What is their role in nature?
Ceriodaphnia reticulata, a common cladoceran species found in US lakes. This is a female carrying two (orange) eggs in her brood chamber. Photo by Florida Sea Grant under a CC BY-NC-ND 2.0 license
Cladocerans play a key role in the functioning of freshwater ecosystems. Primarily, they are a central link in food chains: continuously filtering water and consuming phytoplankton, bacteria, and organic particles, these tiny crustaceans regulate the intensity of algal blooms, maintain water transparency, and control algal numbers. Thanks to cladocerans, many processes in aquatic ecosystems remain balanced, and they themselves serve as a crucial food source for the fry of most freshwater fish and predatory insect larvae. Without them, many species simply could not survive their early stages of development.
Thus, cladocerans perform the function of ecosystem sanitizers. By filtering water, they cleanse it of fine organic debris and bacteria, acting as a natural “microbial vacuum” that maintains freshwater quality.
Finally, these crustaceans are very sensitive to changes in the aquatic environment. Some cladocerans quickly react to changes in salinity, the presence of heavy metals, toxic substances, and other types of pollution. Thanks to this sensitivity, cladocerans are widely used in water quality biotesting, making them a valuable tool for environmental monitoring.
How do they survive?
Bosmina longirostris, а common species of cladoceran zooplankton found in US lakes. Photo by Florida Sea Grant under a CC BY-NC-ND 2.0 license
Cladocerans have an amazing life cycle. Under favorable conditions, they reproduce by parthenogenesis, without the participation of males—females simply clone themselves. This allows them to instantly colonize temporary water bodies after rains or snowmelt.
When “hard times” come—with the onset of cooling, shorter daylight hours, or the drying up of a water body—cladocerans produce resting eggs. These eggs are covered with a strong shell, can withstand drying, frost, and persist in bottom sediments for decades. Sometimes this “cladoceran archive” in the silt is used to study past climatic epochs—like a natural flash drive.
Where do they live?
Almost everywhere, on all continents including Antarctica. They can be found in diverse continental water bodies: rivers, lakes, swamps, ditches, puddles, and other temporary pools. There are even unique species living in leaf axils, tree hollows, damp moss, groundwater, and caves.
The cladocerans of Central Asia are very diverse, where fresh, slightly saline, and saline water bodies are in close proximity—each with its own unique crustaceans.
Why are they important for science?
Daphnia magna is a species of Daphnia (a cladoceran freshwater water flea). Photo: Per Harald Olsen/NTNU. Credit: NTNU, Faculty of Natural Sciences under a CC BY 2.0 license
Cladocerans are an ideal model for ecologists:
They reproduce quickly.
They are easily cultivated.
They instantly react to environmental changes.
They survive climatic changes.
They form the basis of freshwater communities.
Specimens found in permafrost allow scientists to literally “reconstruct zooplankton communities of the past,” comparing populations from different periods, researching evolution in real time, and tracing climate change processes.
Tyva
The Republic of Tyva is one of the most contrasting and unusual regions of Eurasia. Within a relatively small area, almost all of the Earth’s natural zones are found—from semi-deserts and dry steppes to alpine meadows and high-mountain tundras.
Republic of Tyva on the map
The climate in the region is sharply continental, with cold winters, hot summers, large daily temperature fluctuations (up to 30°C), and extremely low precipitation, especially in the steppe basins. The climate in the mountains is milder, with more precipitation, warmer winters, and cooler summers than in the basins. The highest peaks have eternal snow. The highest mountain, Mongun-Taiga, is 3976 meters above sea level. This diversity of natural and climatic conditions creates a wide ecological spectrum.
The landscape mosaic of Tyva is impressive—steppe plains with sand massifs, taiga slopes, high-mountain plateaus, swampy areas, and numerous lakes coexist here. There are about two thousand lakes in Tyva, from large ones like Chagytai and Azas to small brackish and freshwater lakes.
The Ubsunur Basin stands out among the natural landscapes—a unique transboundary natural complex included in the UNESCO World Heritage List. Here, in a small area, one can find desert, steppe, tundra, and alpine meadows, as well as many lakes with varying degrees of mineralization—from almost fresh to hyperhaline.
This combination of contrasting climatic zones, altitudinal gradients, types of water bodies, and salinity levels makes Tuva a natural laboratory for studying aquatic biota.
Dataset
In the course of the research, scientists compiled and summarized the largest dataset to date on the cladocerans of the Republic of Tyva—the result of almost thirty years of field work in the region (1993–2022). A total of 902 water bodies of various types were surveyed: permanent and temporary, differing in depth, altitude, and salinity.
Taiga
Mongun-Taiga is the highest mountain in Tyva
It is important to note that only a few of the lakes located in the basins can be reached by a comfortable road. Most of the water bodies are situated in the mountains, in hard-to-reach areas with difficult mountain roads. The work was incredibly labor-intensive but also exhilarating: our cars broke down high in the mountains far from any settlements, we experienced earthquakes, we had to spend nights near ancient burial mounds, wolves walked near our camp, and marals would occasionally approach us. We even once had to run quickly high in the mountains to escape a thundercloud whose lightning was striking the ground.
The proceess of sampling from reservoirs
The proceess of sampling from reservoirs
The proceess of sampling from reservoirs
Expedition camp
The group of scientists on one of the expeditions: Professor Artem Sinev (Lomonosov Moscow State University, Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences), Natalia Sheveleva (Limnological Institute of the Siberian Branch of the Russian Academy of Sciences), Nadezhda Kirova (Tuvinian Institute for Exploration of Natural Resources of the Siberian Branch of the Russian Academy of Sciences)
The process of sampling from reservoirs
The process of sampling from reservoirs
On one occasion, we fell into a glacial quickstream. These formations, which occur near high-mountain lakes due to the melting of relict ice, suck you into the depths like quicksand, and are incredibly difficult to escape! So this dataset is inextricably linked with a whole series of adventures.
The final dataset, published in Darwin Core Archive format on GBIF, includes 3,599 occurrence records and 76 species of cladocerans. It is noteworthy that not a single invasive species was found in Tyva, although such finds are not uncommon in studies of cladocerans in other regions.
Stopping due to a broken car
Roads high in the mountains
Roads high in the mountains
Stopping due to a broken car
The thunderstorm we were running from
The obtained materials significantly expand the understanding of the composition and spatial distribution of cladocerans in Tyva, which was previously poorly studied from a faunistic perspective.
Nadezda Kirova and Toby
A special mention must be made of the constant members of our expedition team — Toby the dog, who took part in the annual field trips from 2011 onward, growing from a playful puppy into a wise “scientist dog,” and Karkusha the raven, who joined us in 2016 after we found him as a chick with broken legs and decided to keep him. Without exaggeration, both became an integral part of the long-term history of our fieldwork and made their own contribution.
Toby passed away in November 2025, shortly after our research paper was published, at the age of fourteen. It would not be an overstatement to say that he truly devoted his life to these studies, accompanying us year after year and becoming a symbol of the expedition itself.
Research article:
Kirova N, Kirova V, Kotov A (2025) Diversity of the cladocerans (Crustacea, Branchiopoda) in the Republic of Tyva, Russian Federation. Biodiversity Data Journal 13: e163656. https://doi.org/10.3897/BDJ.13.e163656
Decades after it was first found in Japan, a species of crustacean with unique black-and-white coloring that resembles a panda has been confirmed to be new to science. Melitid amphipods are shrimp-like crustaceans found worldwide. The newly classified Melita panda — named after the charismatic mammal — was first found in the 1990s. Details of the discovery and morphological analysis were published in a ZooKeysarticle on 21 September.
A panda sitting on a rock outdoors, holding a bamboo branch
The discovery of the Melita panda highlights the importance of studying species taxonomy, which is the naming and classification of organisms, for conservation efforts. It is impossible to know if a species is in danger of disappearing if it hasn’t even been identified.
“Despite the fact that biodiversity conservation is a global issue, species diversity and other aspects of biodiversity are still not fully understood. As a first step toward species conservation, we conducted a taxonomic study of amphipod Crustacea, which boasts high species diversity around Japan,” said Ko Tomikawa, a professor at Hiroshima University’s Graduate School of Humanities and Social Sciences in Hiroshima, Japan.
A new species of amphipod with a unique panda pattern was found in the intertidal zone of the Japanese coast. Photo credit: Ko Tomikawa/Hiroshima University
Before the discovery of Melita panda, there were 63 known species of Melita amphipods, with 16 of those found in Japan. Melita panda was found in intertidal waters in Wakayama Prefecture, Japan. There are likely even more unidentified and undescribed species of Melita amphipods in Japan’s coastal waters.
“Study on the amphipod Crustacea in the coastal zone of Japan is lagging behind. In order to accurately assess species diversity, taxonomic studies are necessary. We hope the discovery of a new species of amphipod with the familiar coloring of the panda pattern will increase the public’s interest in biodiversity and taxonomy,” said Tomikawa.
A line drawing of Melita panda.
To identify the Melita panda, researchers did both a morphological study and molecular phylogeny using genomic DNA. The morphological description of Melita panda found unique features including its panda-like colors and other physical characteristics, while molecular phylogeny is used to identify how closely related the Melita panda is to other Melita amphipods. This information is used to create a phylogenetic tree or evolutionary tree of the known Melita amphipods. Phylogenetic trees are diagrams that show the evolutionary relationships between species.
A line drawing of Melita Panda‘s gnathopod 1.
The molecular phylogeny found that Melita panda is closely related to two other Melita amphipods, the Melita nagatai and Melita koreana. The panda-like coloring distinguishes Melita panda from these two other amphipods, along with other physical differences. Its gnathopods, which are claws that extend from the second thoracic segment, sit more forward than other Melita amphipods, covering another one of its appendages. Its setae, which are hair-like structures that look like bristles, are also distinguishable from other Melita amphipods. Together, the Melita nagatai, Melita koreana, and newly discovered Melita panda form a monophyletic group. This means they have a common evolutionary ancestor. In this case, it is the Melita hoshinoi.
Looking ahead, researchers will continue to study the Melita panda.
“Hopefully, a detailed study of the ecology and behavior of Melita panda will reveal the reason for its panda pattern,” said Tomikawa.
Beyond Melita panda, Tomikawa emphasized that there is still more to study.
“Further taxonomic studies on amphipods in uninvestigated areas are expected to lead to the discovery of additional new species. Continued taxonomic studies are expected to elucidate the biodiversity in the coastal environments of the Japanese archipelago and provide important basic data for species conservation,” he said.
Other contributors include Shigeyuki Yamato of Shirahama Katata in Wakayama, Japan, and Hiroyuki Ariyama at the Osaka Museum of Natural History in Osaka, Japan.
The Japan Society for the Promotion of Science KAKENHI grants supported this research.
Research article:
Tomikawa K, Yamato S, Ariyama H (2024) Melita panda, a new species of Melitidae (Crustacea, Amphipoda) from Japan. ZooKeys 1212: 267-283. https://doi.org/10.3897/zookeys.1212.128858
After the revision of available type specimens from all available collections in the Russian museums and the Senckenberg Museum in Frankfurt-on-Main, as well as newly collected material in the Black Sea and the North-East Atlantic, a research team of scientists, led by Dr Vassily Spiridonov from Shirshov Institute of Oceanology of Russian Academy of Sciences, re-described Macropodia czernjawskii and provided the new data on its records and updated its ecological characteristics.
Even though recognised in the Mediterranean Sea, the Macropodia czernjawskii spider crab was ignored by scientists (even by its namesake Vladimir Czernyavsky) in the regional faunal accounts of the Black Sea for more than a century. At the same time, although other species of the genus have been listed as Black sea fauna, those listings are mostly wrong and occurred either due to historical circumstances or misidentifications.Now, scientists re-describe this, most likely, only species of the genus occurring in the Black Sea in the open-access journal Zoosystematics and Evolution.
The studied spirder crab species Macropodia czernjawskii in the wild, Tuaphat (near Gelendzhik), Caucasus, Black Sea. Photo by Sergey Anosov
The spider crab genus Macropodia was discovered in 1814 and currently includes 18 species, mostly occurring in the Atlantic and the Mediterranean. The marine fauna of the Black Sea is predominantly of Mediterranean origin and Macropodia czernjawskii was firstly discovered in the Black Sea in 1880, but afterwards, its presence there was largely ignored by the scientists.
After the revision of available type specimens from all available collections in the Russian museums and the Senckenberg Museum in Frankfurt-on-Main, as well as newly collected material in the Black Sea and the North-East Atlantic, a research team of scientists, led by Dr Vassily Spiridonov from Shirshov Institute of Oceanology of Russian Academy of Sciences, re-described Macropodia czernjawskii and provided the new data on its records and updated its ecological characteristics.
“The analysis of the molecular genetic barcode (COI) of the available material of Macropodia species indicated that M. czernjawskii is a very distinct species while M. parva should be synonimised with M. rostrata, and M. longipes is a synonym of M. tenuirostris”,
states Dr Spiridonov sharing the details of the genus analysis.
All Macropodia species have epibiosis and M. czernjawskii is no exception: almost all examined crabs in 2008-2018 collections had significant epibiosis. It normally consists of algae and cyanobacteria and, particularly, a non-indigenous species of red alga Bonnemaisonia hamifera, officially reported in 2015 at the Caucasian coast of the Black Sea, was found in the epibiosis of M. czernjawskii four years earlier.
“It improves our understanding of its invasion history. Museum and monitoring collections of species with abundant epibiosis (in particular inachid crabs) can be used as an additional tool to record and monitor introduction and establishments of sessile non-indigenous species,”
suggests Dr Spiridonov.
The spider crab species Macropodia czernjawskii in the wild, Tuaphat (near Gelendzhik), Caucasus, Black Sea. Photo by Sergey Anosov
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Original source:
Spiridonov VA, Simakova UV, Anosov SE, Zalota AK, Timofeev VA (2020) Review of Macropodia in the Black Sea supported by molecular barcoding data; with the redescription of the type material, observations on ecology and epibiosis of Macropodia czernjawskii (Brandt, 1880) and notes on other Atlanto-Mediterranean species of Macropodia Leach, 1814 (Crustacea, Decapoda, Inachidae). Zoosystematics and Evolution 96(2): 609-635. https://doi.org/10.3897/zse.96.48342
A study of parasitic crustaceans attaching themselves inside the branchial cavities (the gills) of their fish hosts was recently conducted in order to reveal potentially unrecognised diversity of the genus Elthusa in South Africa.
While there had only been one species known from the country, a new article published in the open-access journal ZooKeys adds another three to the list.
For one of them, the research team from North-West University (South Africa): Serita van der Wal, Prof Nico Smit and Dr Kerry Hadfield, chose the name of the fictional character Xena, the warrior princess. The reason was that the females appeared particularly tough with their characteristic elongated and ovoid bodies. Additionally, the holotype (the first specimen used for the identification and description of the previously unknown species) is an egg-carrying female.
Formally recognised as Elthusa xena, this new to science species is so far only known from the mouth of the Orange River, Alexander Bay, South Africa (Atlantic Ocean). It is also the only Elthusa species known to parasitise the intertidal Super klipfish (Clinus supercilious). In fact, this is the first time an Elthusa species has been recorded from any klipfish (genus Clinus).
van der Wal S, Smit NJ, Hadfield KA (2019) Review of the fish parasitic genus Elthusa Schioedte & Meinert, 1884 (Crustacea, Isopoda, Cymothoidae) from South Africa, including the description of three new species. ZooKeys 841: 1-37. https://doi.org/10.3897/zookeys.841.32364
Two new species of tiny symbiotic shrimps are described, illustrated and named by biology student at Leiden University Werner de Gier as part of his bachelor’s research project, supervised by Dr. Charles H. J. M. Fransen, shrimp researcher of Naturalis Biodiversity Center (Leiden, the Netherlands).
Inspired by the extremely hairy feet of one of the species, the authors decided that they should honour Middle Earth’s greatest halfling, Bilbo Baggins.
The newly described shrimps were collected during the Ternate expedition to the Indonesian islands of Tidore and Ternate, organised by Naturalis Biodiversity Center and the Indonesian Institute of Sciences (LIPI) in 2009.
Typically for the Odontonia species, the new shrimps do not reach sizes above a centimetre in length, and were found inside tunicates. It is believed that these symbiotic crustaceans are fully adapted to live inside the cavities of their hosts, which explains their small-sized and smooth bodies.
Photo by Charles Fransen.
Unlike most Odontonia species, which live inside solitary tunicates, the new species Odontonia plurellicola was the first one to be associated with a colonial tunicate. These tunicates have even smaller internal cavities, which explains the tiny size of the new species.
To determine the placement of the new species in the tree of life, the scientists compared the shrimps’ anatomical features, including the legs, mouthparts and carapace. As a result, they were assigned to Odontonia. Further, the available genetic information and Scanning Electron Microscope (SEM) images of the unusual feet of the newly discovered shrimp provided a new updated identification key for all members of the species group.
“Being able to describe, draw and even name two new species in my bachelor years was a huge honour. Hopefully, we can show the world that there are many new species just waiting to be discovered, if you simply look close enough!” says Werner de Gier, who is currently writing his graduate thesis at Naturalis Biodiversity Center and working together with Dr. Charles Fransen on crustaceans.
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Original source:
de Gier W, Fransen CHJM (2018) Odontonia plurellicola sp. n. and Odontonia bagginsi sp. n., two new ascidian-associated shrimp from Ternate and Tidore, Indonesia, with a phylogenetic reconstruction of the genus (Crustacea, Decapoda, Palaemonidae). ZooKeys 765: 123-160. https://doi.org/10.3897/zookeys.765.25277
‘Green-eyed hermit crab’ is the common name for a new species recently discovered off the West Coast of South Africa. Apart from its magnetic stare, however, there is a number of characteristic morphological traits and an unusual home preference that all make the crustacean unique.
Formally named after the University of Cape Town (UCT) alumnus Dr Lara Atkinson, the new hermit crab Paragiopagurus atkinsonaeis described by PhD candidate Jannes Landschoff, UCT, and Dr Rafael Lemaitre, Smithsonian Institution, USA, in the open access journal ZooKeys.
The Green-eyed hermit crab measures merely 70 mm in length and sports a coloration of mottled orange nuanced with cream to white. Among its distinct traits is the significant sexual dimorphism, where the males grow much larger right chelipeds in comparison to females.
Much like other hermit crabs in its family (Parapaguridae), the little crustacean does not use the shells of other molluscs to shelter its vulnerable body, but rather finds a home in the soft, polypy masses built from sand and material created by sea anemones which go on to live on the backs of these crabs in an amazing symbiosis.
“So, when you hold it [the hermit crab], it’s just organic material glued together with some sand,” explains Jannes in the UCT’s announcement about their discovery.
“Even more curiously, parapagurids start off in the usual way, occupying a tiny gastropod shell. But these eventually become deposited within this non-calcified ‘amalgam’ created by the anemones. As the hermit crab grows, its live ‘shell’, or carcinoecia, grows with it.”
The new species was discovered during a three-week survey back in 2013, conducted by the Department of Forestry and Fisheries and the South African Environmental Observation Network in the shallower deep waters (199 m to 277 m) off the West Coast of South Africa. Lara was on board one of the vessels when an unusual green-eyed crab turned up among the numerous specimens collected in one of the trawls. It was at that moment that she noticed that there was something peculiar about it and sent it for identification.
Restricted to a surprisingly small area for no obvious reason, the new species might be just bringing up some very important conservation messages.
“The area isn’t noticeably biologically or oceanographically distinct, but more detailed sampling from the area will tell us more about the habitat conditions. Future studies need to take this into account and give the area more research attention. If there’s something unusual about the site, you’d want to be careful, especially with mining operations along the West Coast,” says Jannes.
“Incidents like these are flags for future protection. The bottom line is we know so little about these offshore habitats from an ecological point of view. And if you’re planning for a marine protected area, you have to know what it is you’re protecting in that area.”
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Original source:
Landschoff J, Lemaitre R (2017) Differentiation of three common deep-water hermit crabs (Crustacea, Decapoda, Anomura, Parapaguridae) from the South African demersal abundance surveys, including the description of a new species of Paragiopagurus Lemaitre, 1996. ZooKeys676: 21-45. https://doi.org/10.3897/zookeys.676.12987
Although the Santa María-La Reforma lagoon complex in the Gulf of California is one of the most important areas for shrimp fishery, little is known about the crustacean species that live in the burrows dug in the bottom.
In addition to presenting two species new to science, researchers Drs. José Salgado-Barragán, Universidad Nacional Autónoma de México, Manuel Ayón-Parente and Pilar Zamora-Tavares, both affiliated with Universidad de Guadalajara, México collaborated to build on the knowledge of small shrimp species living there. The study is published in the open access journal ZooKeys.
Over the span of about two years – between 2013 and 2015, the scientists conducted series of surveys of the bottom-dwelling crustaceans in Bahía Santa María-La Reforma lagoon, located in the southwest Gulf of California. Following a thorough examination of the collected specimens, they recorded five shrimp species of three genera, inhabiting burrows dug into either mud, sand, or sandy-mud. Two of these species turned out to be previously unknown.
One of the new species is named Alpheus margaritae after Dr. Margarita Hermoso-Salazar, a caridean shrimp expert who helped the authors with the identification of the species. This new crustacean lives in the intertidal zone, where it hides in soft mud and gravel of shells and rocks. So far, it is known exclusively from the coastal lagoon Bahía Santa María-La Reforma, Sinaloa, Mexico. Among its characteristic traits are creamy-white colouration splashed with sparse olive green to light brown patches.
The second new species, Leptalpheus melendezensis, is reported to live in the fine sand of the beach. It is named after the Melendez island – the only locality the species has been identified from. Unlike the rest seven members of its genus (Leptalpheus), its major cheliped lacks adhesive disks.
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Original source:
Salgado-Barragán J, Ayón-Parente M, Zamora-Tavares P (2017) New records and description of two new species of carideans shrimps from Bahía Santa María-La Reforma lagoon, Gulf of California, Mexico (Crustacea, Caridea, Alpheidae and Processidae). ZooKeys 671: 131-153. https://doi.org/10.3897/zookeys.671.9081
A new species of terrestrial crab has been found to climb trees on the eastern coast of Hong Kong. All specimens spotted during the survey have been collected at a height of approximately 1.5 – 1.8 m, walking on the bark of the branches at ebbing and low tides. The species is described in the open access journal ZooKeys.
Among the crab’s characteristic traits are squarish predominantly dark brown carapace, very long legs and orange chelipeds. The species is less than a centimetre long, with the studied specimens measuring between 8 and 9 millimetres, irrespective of their sex. However, the chelipeds of the males appear stout, while in females they are distinctly more slender.
The scientists who found the new species (Haberma tingkok), Dr. Stefano Cannicci, the Swire Institute of Marine Science at the University of Hong Kong, and Dr. Peter Ng, National University of Singapore, have placed the new species in a small genus, which now contains merely three species. In fact, Dr. Peter Ng has been involved in the discovery of all of them. He also led the team that established the genus 15 years ago, having collected a small previously undescribed species of mangrove crab from Singapore.
The discovery of the tiny crustacean once again proves how little is known about the diversity of these crabs in Hong Kong. Furthermore, the mangroves that make for the habitat of the new species are under severe impact by both pollution and land reclamation, which underlines the urgent need for their conservation.
Earlier this year, Dr. Peter Ng teamed up with Dr. Jose Christopher Mendoza to describe another new species of crab, collected from the rubble at the island of Guam and named after two of the main characters in J. K. Rowling’s Harry Potter fantasy series.
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Original source:
Cannicci S, Ng PLK (2017) A new species of micro-mangrove crab of the genus Haberma Ng & Schubart, 2002 (Crustacea, Brachyura, Sesarmidae) from Hong Kong. ZooKeys 662: 67-78. https://doi.org/10.3897/zookeys.662.11908
