Tag: Mexico

Cozumel Dwarf Fox Survival Confirmed by Photos After Two Decades

After 20 years without any visual proof, photos now published in the Neotropical Biology and Conservation journal confirm the survival of the cryptic Cozumel dwarf fox.

We at Pensoft Publishers, asked Travis Bayer, the founder of Pathos Wildlife, several questions about his work with one of the world’s most mysterious carnivores, namely the Cozumel Dwarf Fox from Cozumel Island, Mexico.

The research he led was recently published in our open-access journal, Neotropical Biology and Conservation.

In this Q&A, Travis takes us behind the scenes of his study to discuss what first motivated him to track this cryptic species, what they currently know of its fragile conservation status, and the urgent measures needed to protect it from extinction.

Pensoft (P): What motivated your and your team to conduct research?

Travis Bayer (TB): Cozumel sits along the Great Mesoamerican Reef, the second largest reef system on Earth and one of the world’s most renowned scuba diving destinations. I first visited the island back in early 2023 to experience it for myself. At the core of my career as a biologist and conservationist is a lifelong love and fascination for animals, which is why I always look up the native wildlife and try to see them wherever I go.

That is when I had found out about Cozumel’s incredible level of endemism, higher than any other island in Mexico. Above its biodiverse waters lie terrestrial ecosystems hosting dozens of species and subspecies found nowhere else on Earth. Even more fascinating is three of them being dwarfed mammalian carnivores: the pygmy raccoon (Procyon pygmaeus), dwarf coati (Nasua nelsoni), and Cozumel fox (Urocyon sp.).

This is quite unusual given carnivores are generally less likely to become dwarfed or persist on small, resource-limited islands because of their space and energy requirements. Yet on Cozumel, this pattern occurs across multiple species.

I naively thought I might encounter the fox if I searched hard enough, but I ultimately returned home without seeing one. However, the question of whether they still persisted never really left my mind.

I turned my curiosity into an investigation, scouring scientific literature for every recorded mention of the Cozumel fox. The only physical evidence of its existence came from subfossil bones excavated from Mayan archaeological sites. These 500-to-1,500-year-old adult bones were 60-80% smaller than mainland foxes, suggesting they have been evolving in isolation for at least 5,000 to 13,000 years. This warrants a distinct species designation, yet without modern evidence, the Cozumel fox remains scientifically undescribed and legally unprotected.

The consensus of their critically endangered or possibly extinct status comes from generalized surveys documenting the other carnivores, which failed to detect the fox. While no field study has ever detected the fox, I found that none have ever targeted them specifically.

Previous camera trap studies used general baits like sardines and cat food, which heavily attract a broad range of species such as the omnivorous raccoons and coatis. Extremely rare animals also often require broader coverage, longer deployment times, and targeted placement in remote habitat, making study design crucially important. This is when I decided to turn my interest into action, and began planning the first-ever systematic, targeted survey in search of the Cozumel fox.

A scenic view of Laguna Colombia State Reserve, one of the largest remaining protected natural areas on Cozumel. The reserve is the site of historical Cozumel fox sightings recorded in 1995 and 2001, as well as the area where the first photographic evidence of the species was captured by author Rafael Chacón. As a result, it is currently considered some of the most likely remaining habitat for the Cozumel fox.

Shortly after, the ultimate driving force for our motivation surfaced: in September 2023, the first-ever photographs of a living Cozumel fox were uploaded to iNaturalist by Rafael Chacón, Director of Conservation and Environmental Education for La Fundación de Parques y Museos de Cozumel (FPMC). For a species many believed extinct, seeing those images was surreal. It proved the fox was still out there, and the urgency to protect it skyrocketed.

Cozumel fox (Urocyon sp.) — The first photograph ever captured of a Cozumel fox (*Urocyon sp.*), uploaded to iNaturalist in September, 2023. For a species long thought to be possibly extinct or at best extremely rare, this record provided the first visual confirmation that the fox was still persisting on the island. Credit to Rafael Chacón.

We established a partnership to launch a dedicated camera trap survey. When I asked Rafael what motivated him, he told me:

“Photographing the Cozumel gray fox was a very special moment because it represents one of the island’s unique endemic species. Capturing these images helps create awareness about its presence and the importance of protecting its habitat. What motivates me to continue is the responsibility to help future generations understand and value Cozumel’s biodiversity.”

Formally publishing these photographs in Neotropical Biology and Conservation changed this from an anecdotal sighting into a permanent scientific record. Species cannot be protected if their existence remains contested or overlooked. We hope this work lays the foundation for future research, conservation planning, and official taxonomic recognition.

Full-body photograph of adult male Cozumel fox following release in Laguna Colombia State Reserve. Photo credit to Rafael Chacón.
Side profile of the Cozumel fox. Photo credit to Rafael Chacón.
Full-body photograph of adult male Cozumel fox following release in Laguna Colombia State Reserve. Photo credit to Rafael Chacón.

P: You describe the species’ conservation status as “likely critical.” What are the biggest threats to the Cozumel fox today?

TB: The biggest challenge is that we still know almost nothing about its population size, distribution, or ecology. That uncertainty makes effective conservation incredibly difficult, and the lack of a formal taxonomic description limits our ability to implement legal protections.

Spatial distribution of dwarf fox records across land use and vegetation types on Cozumel. The red dot outlined in black indicates the location where the fox was photographed in September 2023. White stars denote historical dwarf fox sightings from 1984 and 1985 (Cuarón et al. 2004), and the black stars indicate recent sightings observed by the authors (R. Chacón, unpublished data 2025; Bayer and McGreal, unpublished data 2026). Credit to Bayer et al., 2026.

However, based on what we know about island ecosystems, several major threats stand out:

Habitat Loss & Fragmentation: Rapid development driven by tourism, cruise ship infrastructure, and expanding hotels places immense pressure on remaining natural habitats.

The Coastal Highway: Cozumel has one major highway looping the island that cuts directly through critical transition zones between coastal and interior habitats. Wildlife-vehicle collisions occur at alarming rates. This poses a massive threat to carnivores who need to move freely to maintain genetic connectivity, find resources, and adapt to seasonal water availability.

Introduced & Invasive Species: Free-ranging domestic dogs compete for resources and introduce deadly disease risks to a small, isolated population. Concurrently, invasive predators like boa constrictors, margays, and ocelots create intense pressure through competition and direct predation. The growing abundance of introduced margays and ocelots is a relatively recent, alarming concern.

Climate Change & Rarity: As a low-lying Caribbean island, Cozumel is highly vulnerable to intensifying hurricanes and storm surges. Because the fox population is already so small, they are inherently vulnerable to genetic bottlenecks and random catastrophic events.

P: What conservation measures could be undertaken to help protect the species?

TB: The most urgent priority is establishing a long-term research and monitoring program focused specifically on the fox. Before we can implement meaningful protections, we must understand exactly where they survive, how many are left, and what habitats they depend on.

A deceased Dwarf coati (Nasua nelsoni) — A deceased dwarf coati (*Nasua nelsoni*), one of Cozumel’s three endemic carnivores, found along the coastal highway after a vehicle collision. As this road cuts through critical habitat transitions, wildlife-vehicle collisions remain a major conservation concern, particularly for species that depend on landscape connectivity between coastal and interior ecosystems.

To achieve these goals, we must prioritize mitigating road mortality by installing dynamic speed feedback signs to slow highway traffic and improve habitat connectivity. Additionally, we need to manage invasive and domestic animals through responsible pet ownership, sterilization programs, and the removal or relocation of invasive predators like margays to minimize disease and predation risks. Finally, because conservation is a collective responsibility, we must foster robust community involvement and public awareness to educate residents and visitors about the Cozumel fox, thereby securing the local support and cooperation vital for these measures to succeed.

Margay (Leopardus wiedii) from camera trap — Captured during the most recent camera trap deployment on Cozumel, this image documents a Margay (*Leopardus wiedii*), an introduced carnivore on the island. Its presence adds to growing concerns about non-native and expanding predator populations, and their potential to intensify competition and predate on Cozumel’s endemic wildlife.

P: Are there any other comments or insights from this research that you think might be of particular importance to the broader public?

TB: One of the most important takeaways from this research is that species can quietly disappear without the world even realizing they are gone. It had been over 20 years since the last anecdotal report of the fox, and almost 30 years since the last confirmed sighting. The Cozumel fox likely represents an ancient island lineage that has evolved in isolation for thousands of years, yet until recently there was no photographic evidence that it was even still alive.

“Their life depends on you. Drive with caution.” A message displayed on author Rafael Chacón’s vehicle, serving as a reminder that Cozumel’s wildlife shares the same roads. Vehicle collisions remain a significant source of mortality on the island, making public awareness a key part of conservation efforts.

We often think extinction is something dramatic and obvious, but in reality it can happen gradually and silently, especially for rare species living in remote or understudied habitats. By the time enough data exists to confirm a severe decline, it may already be too late. That is part of what makes documentation like Rafael’s photos so important. It should serve as a reminder of how much biodiversity can still remain overlooked, even in places visited by millions of people every year.

Close up photo of the Cozumel fox. Photo credit to Rafael Chacón.

The rediscovery of the fox isn’t a conservation success story yet, but it is a second chance.

In collaboration with Pathos Wildlife and the FPMC, we are currently conducting one of the largest camera trap surveys ever done on the island. Ultimately, we hope this work moves the Cozumel fox from a little-known, uncertain presence to a protected, well-understood key part of Cozumel’s ecosystems. This project demonstrates that conservation is often most urgent when certainty is lowest, and that uncertainty itself should be our call to action.

We are incredibly grateful to Travis Bayer for giving us a closer look at his and his team’s vital conservation work on the island. To read the formal scientific record and documentation of these historic sightings, check out the recently published paper in Neotropical Biology and Conservation.

Citation:

Bayer TD, McGreal MA, Chacón D. AR (2026) First photographic evidence of an insular dwarf fox (Urocyon sp.) on the island of Cozumel, Mexico. Neotropical Biology and Conservation 21(2): 123-129. https://doi.org/10.3897/neotropical.21.e187967

Tussling tapirs: unexpected aggression in a shy species

Rafael Reyna-Hurtado describes his latest research capturing extreme fighting and vocalisation in tapirs (Tapirus bairdii) in Mexico.

Guest blog post by Rafael Reyna-Hurtado.

In a recent issue of Neotropical Biology and Conservation we published an article titled “Extreme fighting and vocalisation in Tapirus bairdii, observations from aguadas of Calakmul, social arenas for the species.”

In our paper, we describe how a species known to be gentle and shy can initiate serious fights with conspecifics and how agile and aggressive these gentle giants of the Neotropical forests are capable of being.

Baird’s tapir (Tapirus bairdii) adults fighting in an aguada of the Calakmul Biosphere Reserve, Southern Mexico.

We conducted our research in the amazing site of Calakmul Biosphere Reserve, a protected area in Campeche State in Southern Mexico in the heart of the Maya Forest, a forest shared by Mexico, Guatemala and Belize.

In this forest, jaguars, tapirs and herds of white-lipped peccaries roam the forest floor while spider and howler monkeys make their way across the forest canopy, all surrounded by Mayan temples hidden in the trees.

Man holding aloft an antenna on a mountain beside a large forest. — Rafael Reyna-Hurtado.

My research over the last 20 years has been based in ungulates (mammals with hooves). I became passionate about tapirs after I met them for the first time in the tropical forest of Campeche. As a kid who grew up in central Mexico, I never imagined that a creature of that size and weight was still alive and moving silently in the tropical forest of my country.

The gentle and shy behaviour of tapirs has been confirmed by my main research technique: camera traps. For 10 years we have recorded many tapirs visiting ponds at night, walking and sniffing in silence, at a slow pace, and usually in the late hours of the night (before midnight), or the early hours of the day (after 4:00 am).

Baird’s tapir (Tapirus bairdii) female whistling under searching behaviour in an aguada of the Calakmul Biosphere Reserve, Southern Mexico.

Our camera traps always showed tapirs walking silently, slowly and stopping many times to listen and smell for danger. So imagine my surprise when, in the dry season of 2024, one camera showed us 97 videos of tapirs involved in serious fighting, running, chasing, biting each other and whistling for almost two weeks. It changed our perception of tapirs’ behaviour. Yes, they can be gentle, shy animals, but when challenged they can transform into extreme fighters!

Our research also shows that some specific places, like the water ponds of Calakmul, locally named “aguadas”, are not only sources of water for wildlife during the dry season, but also serve as so-called “social arenas”, sites where animals socialise with conspecifics and acquire information on predators. The role of “aguadas” as social arenas for tapirs make these sites a priority for conservation.

Two tapirs captured by a camera trap. — Camera trap image of two Baird’s tapirs (*Tapirus bairdii*).

Knowing the secret behaviour of a shy, rare and endangered animal is a privilege that amazes me anytime I am in the forest, or when I check our camera traps. It is a feeling of being witness to behaviours and ecological relationships that have not changed for thousands of years.

The information is also very valuable for conservation purposes. Places like Calakmul Biosphere Reserve, where animal and plant communities are still in their original composition, are very rare. We must preserve such places as they show us the interesting relationships between animals and plants that have existed for thousands of years and that are key to the survival of these species. We must learn and work together to keep these sites untouched and allow tapirs to be shy and calm, or, from time to time, become serious extreme fighters!

Original source

Reyna-Hurtado R, Huerta-Rodríguez JO, Rojas-Flores E (2025) Extreme fighting and vocalisations in Tapirus bairdii: observations from aguadas of Calakmul, social arenas for the species. Neotropical Biology and Conservation 20(1): 67-78. https://doi.org/10.3897/neotropical.20.e143760

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Tadpoles for dinner? Indigenous community in Mexico reveals a favorite recipe for a particular frog

Tadpoles of the Sierra Juarez brook frog Duellmanohyla ignicolor are consumed in caldo de piedra in the Chinantla region, in Oaxaca, Mexico.

Stone soup (caldo de piedra) is a traditional meal from the Indigenous Chinantla region in the state of Oaxaca, Mexico. Prepared by men, it is made by placing tomato, cilantro, chili peppers, onion, raw fish, salt, and water in a jicara (a bowl made from the fruit of the calabash tree) in a hole dug near a river. Then, the ingredients are cooked by adding red hot rocks to the “pot”.

In 2019, members of the CIIDIR-Oaxaca Amphibian Ecology Laboratory visited Santa Cruz Tepetotutla in the Chinantla region as part of their continued research work in the community’s forests and streams.

“As we observed and recorded the presence of tadpoles, our guide, Mr. Pedro Osorio-Hernández, remarked that one such tadpole was eaten in stone soup”, says Dr Edna González Bernal, one of the researchers.

Local landscape. Photo by Carlos A. Flores

Although not much attention is paid to tadpoles, they are more important than you might think. They are perfect indicators of the health of bodies of water, due to their sensitivity to changes in the aquatic environment where they develop. When tadpoles are present in a stream, river, or even a puddle, they indicate an acceptable concentration of oxygen, pH, conductivity, and temperature, or overall good dynamics of sediments and plant matter. And, above all, finding tadpoles is the easiest way to know about the presence of an amphibian species that reproduces in that site, regardless of whether or not an adult has been observed. Hence, the identification of the unique characteristics of the tadpoles of each species is an important task that is currently drawing more attention amongst scientists.

Duellmanohyla ignicolor tadpoles. Photo by Edna González-Bernal

“For us, as Oaxacans, Don Pedro’s words were an eye-opener”, biologist Carlos A. Flores, also part of the study, continues. “Although we knew about the tradition of stone soup, we would have never imagined that it could be prepared with tadpoles of the Sierra Juárez Brook frog (Duellmanohyla ignicolor)!”

Duellmanohyla ignicolor. Photo by Edna González-Bernal

“As scientists, we wondered: why this species and not another? Since when have these tadpoles been eaten? In what other places are tadpoles consumed and in what form? Does this consumption have a negative effect on amphibian populations?”

To answer these questions, the researchers monitored several streams in the community, collecting data on the structure of these sites, such as depth, water velocity, temperature, etc. They wanted to identify the characteristics of the habitat where the tadpoles of this little known species are found. Their research was recently published in the open-access journal ZooKeys.

The team’s primary interest in the stone soup with tadpoles was to accurately document human interaction with this amphibian species.

“It is common in anthropological literature to document the consumption of tadpoles in Mexico, but rarely does such documentation reach the species level. Even in some ethnoherpetological works, the consumption of tadpoles is mentioned only anecdotally”, Dr González Bernal explains.

**A boy collects tadpoles**. Photo by Edna González-Bernal

“We learned that these larvae tend to form schools: aggregations of several tens to hundreds of individuals. They swim on the surface of the water and move their mouths to feed on suspended particles, which may be remains of plant matter, pollen or insect parts”, she continues.

“This behavior, as has been documented in other species, biologically implies a strategy to feed more efficiently, control body temperature, protect themselves from predators and even to encourage social interaction. At the same time, it makes it easier for humans to capture several tadpoles using nets, hats, bags or even their own hands.”

This tadpole soup is consumed during the hottest months (April and May), when people go swimming in the river. The rest of the year, it is prepared with fish. Local people described the tadpoles as having a delicious fish-like flavor.

Why do people eat these particular tadpoles? Community members remarked that, because they are found at the surface of the water, they are considered cleaner than those found at the bottom, such as the tadpoles of the the coastal toad (Incilius valliceps) and the gloomy mountain frog (Ptychohyla zophodes). In addition, the tadpoles consumed in the stone broth reach sizes of up to 5 centimeters, which makes them a better choice for the dish.

Tadpoles caught using caps. Photo by Edna González-Bernal

Is stone soup a dish that only exists in the Chinantla region? “We found that while the dish has primarily been documented in this region, it is also consumed in some Indigenous Ayuk (Mixe) municipalities,” Dr González Bernal says.

The cooking principle itself is a technique that has been used throughout history by different cultures around the world. The particularity of the caldo de piedra lies in its preparation with tomato, cilantro, and chili peppers, as well as prawns or particular species of fish such as the bobo (Joturus prichardi).

In the case of the Sierra Juarez Brook frog’s tadpoles, the researchers concluded that since they are consumed locally and for non-commercial purposes, the species is not at risk. However, the behavior of these tadpoles and their preference for deeper water bodies make them vulnerable to being caught in large quantities.

“In the context of the global amphibian crisis, it is of utmost importance to continue increasing our knowledge about the diversity of species and above all to delve deeper into their ecology, both at the adult and larval stages. Only in this way can we gain a greater understanding of each species’ needs and develop conservation strategies that take into account the biology of species with a complex life cycle, such as amphibians”, the research team says in conclusion.

Research article:

Flores CA, Arreortúa M, González-Bernal E (2022) Tadpole soup: Chinantec caldo de piedra and behavior of Duellmanohyla ignicolor larvae (Amphibia, Anura, Hylidae). ZooKeys 1097: 117-132. https://doi.org/10.3897/zookeys.1097.76426

Man’s best friend could be a jaguar’s next meal: A case study from the Mexican Caribbean

Events of jaguars predating on and attacking dogs are poorly documented throughout the Americas. Researchers from Mexico and Germany report in detail jaguar attacks on 20 dogs at a tourist site in the Mexican Caribbean. In addition, they describe an initiative proposed by locals as well as national and international NGOs to prevent human-jaguar conflicts due to pet predation. The study was published in the open-access journal Neotropical Biology and Conservation.

Mahahual is a small fishing village in the Mexican Caribbean that receives a large number of tourists every year. Over the past 15 years, its population has increased rapidly, and, as a result, people have started to settle in areas away from the main center of the village, sometimes encroaching on jaguar habitats. As most of those people keep guard dogs on their properties, jaguars have taken advantage of this situation by wandering near people’s houses at night, and sometimes those dogs end up as a night-time snack for the big cats.

A jaguar is photographed wandering around houses looking for dogs. Photo by Víctor Rosales

Unlike jaguar attacks on livestock, attacks and predation on other domestic species such as dogs have only been documented anecdotally (through interviews or from remains found in faeces). Such attacks can indeed lead to pet predation conflict, which can ultimately have a negative impact on the jaguar populations. Attachment to pets may lead humans to start killing the big cats, which is of particular concern for an endangered species like the jaguar. Furthermore, it is possible that a wide range of pathogens may be transmitted from dogs to jaguars, further threatening the health of jaguar populations in Mahahual.

A dog injured as a result of a jaguar attack in Mahahual, Quintana Roo, Mexico. Photo by Víctor Rosales

This is why a multidisciplinary team made up of veterinarians, conservationists, locals, NGOs (Aak Mahahual A.C. and International Fund for Animal Welfare (IFAW)) and researchers (El Colegio de la Frontera Sur and Universidad Tecnológica de Calakmul), led by Dr Jonathan Pérez Flores, began investigating the occurrence of jaguar predation and attacks on dogs at the Mexican Caribbean tourist site from almost 10 years ago. Their research was just published in the open-access journal Neotropical Biology and Conservation.

According to their report, the behaviour of Mahahual’s jaguars resembles that of Indian leopards, which have already turned dogs into an important component of their diet, preferring them over livestock. Jaguars and leopards usually attack from a blindside, biting the dogs on the neck or head to avoid counterattacks. Similarly to leopards, jaguars attack at night and kill more dogs during the dry season. This is likely due to the fact that it’s easier for jaguars to hunt dogs than their natural prey: armadillo, lowland paca, brocket deer, white-tailed deer. Furthermore, the latter are less available during the dry season.

One of the night houses built by the people of Mahahual, Aak Mahahual A.C. and International Fund for Animal Welfare (IFAW). Photo by Francisco Rubén Castañeda

In 2017, the people of Mahahual partnered with Aak Mahahual A.C. and IFAW to build protective night houses made of wood and wire mesh meant to keep dogs safe at night. So far, they’ve built 38 such houses to prevent jaguar attacks. Sterilisation and vaccination campaigns have also been intensified since late 2020 to prevent the transmission of diseases between the two species.

Thanks to this study, we now have a better understanding of the adaptability and persistence of jaguars in human-dominated landscapes and the impact of dog predation by jaguars. However, the authors call for more research in the area to help paint the full picture.

Research article:
Carral-García M, Buenrostro I, Weissenberger H, Rosales V, Pérez-Flores J (2021) Dog predation by jaguars in a tourist town on the Mexican Caribbean. Neotropical Biology and Conservation 16(4): 461-474. https://doi.org/10.3897/neotropical.16.e68973

A new species of Darwin wasp from Mexico named in observance of the 2020 quarantine period

“We thought that it was a good idea to remember this extraordinary year through the name of one remarkable species of Darwin wasp found in seven Mexican States (including Tamaulipas, where the UAT campus is located) and also Guatemala,” comment the researchers who discovered the previously unknown species.

Scientists at the Autonomous University of Tamaulipas (UAT) in Mexico recently discovered five new species of parasitoid wasps in Mexico, but the name of one of them sounds a bit weird: covida. Why this name?

In fact, the reason is quite simple. The thing is that the team of Andrey Khalaim (also a researcher at the Zoological Institute of Russian Academy of Sciences in Saint Petersburg, Russia) and Enrique Ruíz Cancino discovered the new to science species during the 2020 global quarantine period, imposed due to the COVID-19 pandemic. Their findings are described in a newly published research article, in the peer-reviewed, open-access scientific journal ZooKeys.

“We thought that it was a good idea to remember this extraordinary year through the name of one remarkable species of Darwin wasp found in seven Mexican States (including Tamaulipas, where the UAT campus is located) and also Guatemala,”
explain the scientists.

The new species, which goes by the official scientific name Stethantyx covida, belongs to the Darwin wasp family Ichneumonidae, one of the most species-rich insect families, which comprises more than 25,000 species worldwide.

“Darwin wasps are abundant and well-known almost everywhere in the world because of their beauty, gracility, and because they are used in biological control of insect pests in orchards and forests. Many Darwin wasp species attack the larvae or pupae of butterflies and moths. Yet, some species are particularly interesting, as their larvae feed on spider eggs and others, even more bizarre, develop on living spiders!”
further explain the authors of the new study.

Stethantyx covida is a small wasp that measures merely 3.5 mm in length. It is predominantly dark in colour, whereas parts of its body and legs are yellow or brown. It is highly polished and shining, and the ovipositor of the female is very long and slender.Along with Stethantyx covida, the authors also described four other Mexican species of Darwin wasps from three different genera (Stethantyx, Meggoleus, Phradis), all belonging to the subfamily Tersilochinae. Some tersilochines are common on flowers in springtime. While the majority of them are parasitoids of larvae of various beetles, some Mexican species attack sawflies, inhabiting the forests.

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Original source:

Khalaim AI, Ruíz-Cancino E (2020) Contribution to the taxonomy of Mexican Tersilochinae (Hymenoptera, Ichneumonidae), with descriptions of five new species. ZooKeys 974: 1-21. https://doi.org/10.3897/zookeys.974.54536

How many sharks, chimaeras, skates, and rays inhabit Mexico?

Worldwide, Mexico is well-known for a lot of things: its cuisine, tequila, mariachis, pyramids, and beaches, as well as being the country with the most Spanish-speaking residents (more than 120 million people).

In contrast, however, little is known for the country’s chondrichthyan fauna: a class of fishes containing the sharks, chimaeras, rays, and skates.

To fill the gap in the knowledge of the Mexican marine fauna, scientists from the Instituto Politécnico Nacional – Centro Interdisciplinario de Ciencias Marinas (IPN-CICIMAR) conducted a multidisciplinary study on the extant species of the country’s Economic Exclusive Zone (EEZ) and, as a result, reported a total of 217 extant chondrichthyan species. Their findings are published in the open access journal ZooKeys.

In their updated taxonomic list, the team of Dr. José De La Cruz-Agüero, Dr. Jorge Guillermo Chollet-Villalpando, and Venezuelan graduate students Lorem González-González and Nicolás R. Ehemann report eight chimaeras, 111 sharks and 98 ray and skate species. These numbers equate to 18% of the world’s chondrichthyans.

Split between the Mexican coasts there are 92 species recorded from the Mexican Pacific and the Gulf of California, whereas 94 fishes are identified for the Gulf of Mexico and the Caribbean Sea. Additionally, 31 species are known from both coasts.

“The species richness will undoubtedly continue to increase, due to the current investigations in progress, as well as the exploration of deep-water fishing areas in the EEZ,” comment the scientists.

Considered to be primitive fishes, sharks, skates, chimaeras, and rays are believed to have been inhabiting the planet for the last 420-450 million years. To put it in perspective, the earliest evidence of our species – Homo sapiens – is pretty ‘young’ at 315,000 years.

Not only do these species are peculiar with their lack of a bony skeleton when compared to the more recently evolved fishes, but they also have an unusual digestive system, featuring a spiral valve, where the lower intestine is twisted like a corkscrew to increase the surface area. They don’t have a swimming bladder either. Further, there are about 650 extant species, whereas the known bony fishes are estimated to be over 35,000.

Most of the chondrichthyans are considered either ‘Critically Endangered’ (a classification a step below ‘Extinct’) or ‘Endangered’, according to the Red List of the International Union for Conservation of Nature (IUCN). The majority are also featured in the Convention on International Trade in Endangered Species.

As if to make matters worse, these fishes are also particularly susceptible to overfishing and have a low rate of growth and fecundity (females give birth to between 1 and 25 pups a year).

Original source:

Ehemann NR, González-González LV, Chollet-Villalpando JG, Cruz-Agüero JDL (2018) Updated checklist of the extant Chondrichthyes within the Exclusive Economic Zone of Mexico. ZooKeys 774: 17-39. https://doi.org/10.3897/zookeys.774.25028

Two brand new dung beetle species from montane grazing sites and forests in Mexico

While carrying out a biodiversity study, a Mexican-Italian research team discovered three new dung beetle species in montane forests disturbed by livestock grazing. Mexico has been a mecca for naturalists, and its dung beetle species are among the best known in the world. This is why the discovery of new species there is noteworthy. The present study, published in the open-access journal ZooKeys, describes two of them and highlights the need to further explore the biodiversity of disturbed ecosystems.

Mexico is a country that holds a vast number of creatures and ecosystems. There is in fact a fascinating phenomenon: tropical forests that have close affinities with South America co-occurring with temperate and arid areas shared with North America. Thus, Mexico has been particularly attractive to explorers ever since the 19th century.

A group of animals that has woken up a special interest for studies in Mexico is the so-called ‘dung beetles’. As their name suggests, dung beetles are insects that feed mainly on mammal faeces.

For decades, an international research team, led by Dr Gonzalo Halffter, has studied dung beetles across the world, especially in Mexico. As a consequence, the Mexican species are some of the best-known. However, Dr Halffter and his team are not interested exclusively in dung beetles, but also in evolutive phenomena, the effects of land-use change, ecosystems modification by human activities, and conservation biology. Such concerns seem to be of particular importance now that the terrestrial ecosystems in Mexico have been severely destroyed and disturbed by people.

Livestock is one of the major drivers of biodiversity loss worldwide, which makes the present discovery particularly impressive. With at least 58% of the area of Mexico occupied with livestock farming, dung beetles are essential in cleaning up. While studying their diversity at conserved forests and cattle grazing sites across the mountains of Mexico, the researchers found some new species of dung beetles.

The first to discover these new dung beetles was Victor Moctezuma, a student of Dr Gonzalo’s at the Instituto de Ecología of Mexico.

“I was carrying out sampling for my Masters Degree studies, but I had no idea that new dung beetles could be found in a forest that is disturbed by human activities, such as livestock grazing and land-use change,” recalls Moctezuma. “So I was really surprised when I discovered three dung beetle species.” One of these species has already been published.

Apart from the two new dung beetles, formally called Onthophagus clavijeroi and Onthophagus martinpierai, the present paper also provides theories about the current distributions of these insects across the Mexican mountains and their putative evolutive relationships. As a whole, the study highlights the importance of disturbed forest for species discovery and conservation.

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Original source:

Moctezuma V, Rossini M, Zunino M, Halffter G (2016) A contribution to the knowledge of the mountain entomofauna of Mexico with a description of two new species of Onthophagus latreille, 1802 (Coleoptera, Scarabaeidae, Scarabaeinae). ZooKeys 572: 23-50. doi:10.3897/zookeys.572.6763

The third sister: Long-suspected third desert tortoise species proven to exist in Mexico

The huge variability among the desert tortoise populations of Mexico has finally been given an explanation after casting doubts for several decades. The puzzle was solved by an international team of researchers, led by Dr. Taylor Edwards, The University of Arizona, who teamed up to find out whether there has been a previously unknown third sister species all along. Moreover, unlike their predecessors, the team have managed to provide enough evidence to prove its existence. Their study is published in the open-access journal ZooKeys.

Distributed over a large area stretching from the Mojave and Colorado deserts in the United States to mainland Mexico, the tortoise populations were noticed to vary distinctly back in 1945, when scientists pointed out that the southern populations were suspiciously different. However, due to lack of enough samples and, therefore research, there was not enough evidence to prove that they were in fact two separate species.

Over the span of six years, the team of Dr. Taylor Edwards measured a multitude of tortoises during their field trips in Sonora and northern Sinaloa. This is how they concluded that the southern populations stand out with their significantly shorter tails and flatter carapaces. Unlike its sister species, whose shells are medium to dark brown with greenish hues, while the bodies are dark gray to brownish-gray, the new tortoise is dark tan to medium-brownish with an orange cast.

The new species inhabits exclusively thornscrub and tropical broadleaf forests, which is the reason why out of the three it is the one occupying the smallest geographic range, extending over approximately 24,000 km2.

Although there is not much information about their behaviour, it is presumed that the tortoises activity is strongly correlated with the monsoonal rains and the vegetation growth. The biologists have observed that the adults begin their seasonal activity in June, shortly before plant growth and the monsoons. Then, in December, they would cover underground in their dens, where they would spend the dry and cool winter season.

The new species, called Gopherus evgoodei, receives its name in honour of Eric V. Goode, a conservationist, naturalist, and founder of the Turtle Conservancy.

“He has contributed generously to the conservation of this species via the preservation of land in Mexico, and he actively pursues the conservation of turtles and tortoises on a global scale,” point out the researchers. “Eric sets an important precedent by complementing this taxonomic description with a tangible action that contributes to the conservation of the new species in its native habitat”.

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Original source:

Edwards T, Karl AE, Vaughn M, Rosen PC, Torres CM, Murphy RW (2016) The desert tortoise trichotomy: Mexico hosts a third, new sister-species of tortoise in the Gopherus morafkai-G. agassizii group. ZooKeys 562: 131-158. doi: 10.3897/zookeys.562.6124

Serendipitous orchid: An unexpected species discovered in Mexican deciduous forests

A new elegant orchid species that grows on rocks in deciduous forests of the Pacific slope of Oaxaca state, Mexico, has finally put an end to a long standing dispute among taxonomists. ‘Sheltered’ under the name of a close relative, the plant has been proved by a research team, led by Dr. Leopardi-Verde, to be different enough for a species of its own. Its distinct features, including shape, size and colors, are discussed and published in the open-access journal PhytoKeys.

When scientists Drs. Carlos L. Leopardi-Verde, Universidad de Colima and Centro de Investigacion Cientifica de Yucatan, German Carnevali and Gustavo A. Romero-Gonzalez, both affiliated with Centro de Investigacion Cientifica de Yucatan and Harvard University Herbaria, stumbled across a beautiful orchid in bloom, they found themselves so surprised by its unique colors and forms that later on they chose the specific epithet inopinatus, meaning “unexpected”.

One of the most distinctive characters of the new plant is the yellow labellum patterned with crimson to reddish brown lines. Typically for its species complex, this orchid’s leaves are wide and leatherlike and the flowers are relatively large, showy, and leathery to fleshy-leathery petals and sepals. The color of the flowers varies from bronze-green with dark purple lines near the base to pale pink and creamy white splashed with reddish-brown spots and lines towards the top.

The plant is between 30 and 42 cm tall, while together with its flowers it reaches between 80 and 90 cm. Each branch of the inflorescence bears from 3 to 8 flowers, which bloom between March and July. Having been recorded only from a few sites on the Pacific slope of Oaxaca state, Mexico, the species appears to be rare.

The authors explain the similarities between the new species and its close relatives. They also discuss the long-held confusion about its taxonomic placement. As a result of the study, a hypothesis about hybridization that has played a role in the evolution and origin of the novelty has been refuted.

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Original source:

Leopardi-Verde CL, Carnevali G, Romero-Gonzalez GA (2016) Encyclia inopinata (Orchidaceae, Laeliinae) a new species from Mexico. PhytoKeys 58: 87-95. doi: 10.3897/phytokeys.58.6479

How to catch a small squid? First records for the Gulf of California and southwest Mexico

Often avoiding sampling gear with their capability to detect movements and swim their way out of the nets fast enough, the small squids living in the open-ocean zone have so long gone under-researched. The present study, conducted by Dr. Michel Hendrickx, Universidad Nacional Autonoma de Mexico, and his team, seems to provide new and first distributional records of five such species for the Gulf of California and in southwestern Mexico. It also significantly expands the currently known southernmost limit of localities of some of these squids in the eastern Pacific. The research is available in the open-access journal ZooKeys.

The researched five squid species belong to two genera, Abraliopsis and Pterygioteuthis, which although abundant and diverse, have long been shrouded by taxonomic and distributional controversies. To solve them, the researchers used specimens, collected over the span of thirteen years, comprising eight cruises across 113 locations in the Gulf of California and off the southwestern coast of Mexico.

As a result, the scientists concluded a significantly wider distributional range of the species they found. For instance, squids of the Abraliopsis genus were surprisingly found in water deeper than 600 m during the day.

The studied small squids are of high ecological value due to their vital position in the food web. Members of Abraliopsis are important preys for many fishes and mammals, such as the peruvian hake, the Indo-Pacific sailfish, the common dolphinfish and the local sharks. Meanwhile, the representatives of the other researched genus, Pterygioteuthis, are often consumed by larger cephalopods, sea-birds and fur seals. However, their abundance is strongly dependent on temperature, especially when there are fast and significant changes.

The scientists suggest that additional samplings with more adequate equipment, like faster large-sized mid-water trawls, could further bridge the knowledge gaps about these elusive marine inhabitants.

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Original source:

Hendrickx ME, Urbano B, Zamorano P (2015) Distribution of pelagic squids Abraliopsis Joubin, 1896 (Enoploteuthidae) and Pterygioteuthis P. Fischer, 1896 (Pyroteuthidae) (Cephalopoda, Decapodiformes, Oegopsida) in the Mexican Pacific. ZooKeys 537: 51-64. doi: 10.3897/zookeys.537.6023.