Influence of seasonality on habitat use and spatial distribution patterns of the buthid Physoctonus debilis in Brazil

 

The chose of habitat is important for scorpions for protection against predators and climate variations and for optimal access to prey. In some areas, climate seasonality has a strong effect on vegetation, and this may have an impact on the habitats chosen by scorpions.

André O. Silva-Júnior and co-workers have recently published a study on habitat use and spatial distribution patterns in a population of the tree-dwelling scorpion Physoctonus debilis (C. L. Koch, 1840) (Buthidae) across different seasonal periods in a Caatinga environment in Brazil.

The study demonstrates that the spatial distribution and habitat use of the tree-dwelling scorpion P. debilis are significantly influenced by seasonal changes, with variations observed among different sexes and developmental stages.

Abstract:
Habitat selection plays a crucial role in the survival of various animals, primarily due to their ability to identify suitable sites for development. In Caatinga regions, climate seasonality has a strong effect on vegetation, consequently influencing the occurrence and spatial distribution of diverse plant-associated organisms. The aim of this study was to analyse habitat use and spatial distribution patterns in a population of the tree-dwelling scorpion Physoctonus debilis (C. L. Koch, 1840) across different seasonal
periods in a Caatinga environment. Sampling was conducted during both dry and rainy seasons, each lasting 3 months, in northeastern Brazil. During each expedition, six plots measuring 30m× 30m and spaced 20m apart were sampled. In addition, the geographic coordinates of each specimen were recorded, and environmental metrics related to tree connectivity and isolation were measured. The results indicate that the population of P. debilis showed a higher occurrence during the dry season (158 individuals) than during the rainy season (105 individuals), with variations according to sex and developmental stage. Female occurrence was more frequently during the dry season, whereas immatures showed a higher occurrence during the rainy season. Our results also revealed spatial aggregation at short distances, with the intensity of aggregation varying among sexes, developmental stages, tree connectivity and climatic seasons. Overall, these results indicate that the spatial distribution of P. debilis is distance-dependent, with stronger spatial aggregation occurring at shorter distances.

Reference:
Silva-Júnior AO, Celante GL, Foerster SÍA, Feitosa MLB, Moura GJB, Lira AFA. Influence of Seasonality on Habitat use and Spatial Distribution Patterns of Tree-Dwelling Scorpion (Physoctonus debilis) in Brazilian Caatinga. New Zealand J Zool. 2026;53(3). [Open Access]

An updated catalogue of the scorpions of Paraguay with biogeographical information

 

Paul Smith and co-workers have recently published a updated review of the scorpion fauna of Paraguay. The country's scorpion fauna seems to consist of at least fifteen species in five genera and three families (Ananteridae, Bothriuridae and Buthidae). 

An identification key for the known species of Paraguay is included and the article also comments on some taxonomic problems and biogeography.

Abstract:
We review and map the current distribution of the Paraguayan scorpion fauna using a hierarchical system of reliability, differentiating specimens examined, specimens not examined and photographic records. One new species (Bothriurus sp.), two new national records (Brachistosternus simoneae and Ananteris mariaterezae), and nineteen new departmental distribution records are reported. The national fauna is concluded to be composed of at least fifteen species in five genera and three families, with one other species considered to be of hypothetical occurrence and a further two of probable occurrence. An illustrated key suitable for identifying Paraguayan material is included, and comments regarding taxonomy and systematic problems that remain to be resolved, together with proven and potential medical significance, are provided.

Reference:
Smith P, Borges A, Santacruz J, Owen M. Catalogue of the scorpions of Paraguay, with an illustrated key and biogeographical assessment (Arachnida: Scorpiones: Ananteridae, Bothriuridae, Buthidae). Invertzool. 2026;23:453–504. [Open Access]

Thanks to Victoria for informing me about this article! 

Delayed Cannibalism in the Brazilian Scorpion Mesotityus pusillus

 

The life as young scorpions are risky and the death rate of young scorpions are quite high. Cannibalism is common in scorpions and it seems that also mother scorpion will prey on their own offspring.  

Lizbeth Sarai Rodríguez‑Medina and co-workers have recently published a study on female cannibalism in the litter-dwelling scorpion  Mesotityus pusillus (Pocock, 1893) (Buthidae) from Brazil. [The genus name for the species is based on Prendini (2026), and the current use name of this taxa in The Scorpion Files is Tityus pusillus Pocock, 1893.]

The study tested if there were differences in offspring discrimination in females (own offspring vs. non-related offspring). Interestingly, there were no differences in predation occurrence and the proportion
of juveniles consumed in the two groups. 

One interesting difference was observed. When females were together with their own offspring, it took longer time for any cannibalism occurred. Even though this difference was quite small, the authors suggest that kin recognition could be one of the explanations for the observed delay.

Abstract:
The small size and limited defensive capacity are factors responsible for the high mortality  of juveniles. Thus, offspring recognition is an important trait for juvenile survival, especially in generalist predators. In this study, we investigated aspects
related to offspring discrimination in females of the scorpion Mesotityus pusillus. A total of 172 juveniles from 32 females were divided into two groups: females with their own offspring and females with unrelated juveniles. Predation events were recorded
daily for 20 days. Predation occurrence and the proportion of juveniles consumed did not differ significantly between groups. Females with their own offspring tended to take longer to initiate predation than females exposed to unrelated juveniles, although this difference was not statistically significant. Our results reveal differences in the timing of cannibalistic behavior without providing clear evidence for consistent

Reference:
Rodríguez-Medina LS, de Araujo Lira AF, Pordeus LM. Delayed Cannibalism in the Litter-Dwelling Scorpion Mesotityus pusillus (Pocock, 1893)(Scorpiones, Buthidae): Evaluating Kin Recognition as a Possible Explanation. Journal of Insect Behavior. 2026;39(2):20. [Open Access]

Taxonomic comments on some species of Bothriurus from Brazil and one new species

 

Wilson Lourenco and co-workers have recently published an article with considerations of some species in Bothriurus Peters, 1861 (Bothriuridae) from the state of Paranà in Brazil. Main findings:

Bothriurus trifinium Lourenço, Wilme & Ythier, 2026 [New species from the Northwest of the state of Paraná in Brazil.]

Bothriurus semiellipticus Prado, 1934 [Raised to species status from synonymy with B. bonariensis (C.L. Koch, 1842).]

Abstract:
A new species, Bothriurus trifinium sp. n. is described from an area of Riparian wet-forests in the Northwest of the state of Paraná in Brazil. The new species can be associated with other species previously described from the nearby regions of Paraná but also from Mato Grosso do Sul and Paraguay. The description of this new species attests once again about the existence of micro-endemic populations within different groups of Bothriurus. Comments are also proposed on the taxonomic status of some previously described species, with one species revalidated and some synonymies suggested.

Reference:
Lourenço WR, Wilmé L, Ythier É. New considerations on the species of the genus Bothriurus Peters (Scorpiones: Bothriuridae) described or cited from the state of Paraná, Brazil and description of a new species. Faunitaxys. 2026;14(56):1–10. [Open Access]

Thanks to Eric for informing me about this article!

Family Bothriruidae 

New book on the biology of neotropical scorpions

 

André Felipe de Araujo Lira and Edmundo González-Santillán are editors for a brand new book on the biology of neotropical scorpions. This book contains a comprehensive review of all aspects of the scorpions in the important neotropical region, which is known both for its high biodiversity and the high number of medical important species.

About the book [from the publisher]

The Biology of Neotropical Scorpions focuses on comprehensive aspects of scorpions of the Neotropical region, such as public health to biogeographic history. This innovative book is devoted to tackling that lack of knowledge and bringing together a bundle of studies to offer students, researchers, and professionals a comprehensive background to start their research with scorpions as model organisms.

Since 1990 the study of scorpions thrived following the tradition focusing on the Palearctic and Neartic fauna, leaving behind ancient and important scorpion fauna localised in the Neotropics. The Neotropical region encompasses the tropical areas from South America to central Mexico, including the Antilles, comprising different biomes in their extension, such as deserts, dry forests, savannas, mountain ranges, and rainforests. These myriad environments influenced scorpions from their venom composition, morphology, and their human interactions.

Many researchers from different areas and countries have generated a growing piece of information about Neotropical scorpions, but this still is fragmentary. This book innovates in the biology of scorpion fluorescence, chromosomal and molecular genetics, conservation ecology, and ethnobiology of scorpions from the perspective of traditional medicine.

Table of content:

1 What Are the Neotropical Scorpions? . . . . . . . . . . . . . . . . . . . . . . . . . . 1
André Felipe de Araujo Lira
2 Allometry and the Evolution of Sexual Size Dimorphism
in Scorpions: Insights from Neotropical Species . . . . . . . . . . . . . . . . . 13
Stênio Ítalo Araújo Foerster
3 Mating or Not? Reproductive Aspects of Sexual Reproduction
and Parthenogenesis in Neotropical Scorpions . . . . . . . . . . . . . . . . . . 31
Gracielle de Fátima Braga-Pereira and André Felipe de Araujo Lira
4 Luminescence and Other Optical Characteristics of Scorpion’s
Exoskeleton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Daniel López-Cabrera, Gabriel Ramos-Ortiz,
Montserrat G. Rivera-Ortiz, Edmundo González-Santillán,
and Rafael Espinosa-Luna
5 Diversity, Taxonomy, and Distribution of Neotropical Scorpions . . . 69
Edmundo González-Santillán, José Antonio Ochoa,
and Andrés Alejandro Ojanguren-Afilastro
6 Advances in the Phylogenomic Relationships of Neotropical
Scorpions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Carlos E. Santibáñez-López and Prashant P. Sharma
7 Fossil Scorpions, with a Focus on the Neotropical Species . . . . . . . . . 151
Jason A. Dunlop
8 Biogeography of Neotropical Scorpions: An Overview . . . . . . . . . . . . 179
Adriano Medeiros DeSouza
and Alessandra Rodrigues Santos de Andrade
9 Subterranean and Troglomorphic Scorpions from the Neotropics . . . 199
Edmundo González-Santillán, Javier Blasco-Aróstegui,
and Jairo A. Moreno-González 
10 Functional Morphology of Predatory and Defensive Behaviour
in Neotropical Scorpions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Yuri Simone
11 Sampling Techniques for Scorpions . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Nancy Lo-Man-Hung and Andria de Paula Santos-da-Silva
12 Cytogenetics of Neotropical Scorpions . . . . . . . . . . . . . . . . . . . . . . . . . 261
Bruno Rafael Ribeiro de Almeida, Jonas Gama Martins,
and Renata Coelho Rodrigues Noronha
13 Neotropical Scorpions as Useful Models for Ecological Studies . . . . . 289
André Felipe de Araujo Lira
14 Traditional Treatment of Scorpion Stings in the Neotropics . . . . . . . 307
Jonas Gama Martins, Bruno Rafael Ribeiro de Almeida,
Pedro Pereira de Oliveira Pardal,
and Rudi Emerson de Lima Procópio
15 Neotropical Scorpion Venom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Juana María Jiménez-Vargas, Jimena Isaias Cid-Uribe,
and Rita Restano-Cassulini
16 Scorpionism in Neotropics: Public Health Issues and Prevention . . . 353
Clara Guerra-Duarte and Ana Luiza Bittencourt Paiva
17 Managing Scorpionism: Envenomation, Diagnostics,
and Therapeutic Approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389
Manuela B. Pucca, Isabela C. dos Santos, and Felipe A. Cerni
18 Perspectives on Biology and Interactions with Humans
of Neotropical Scorpions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Edmundo González-Santillán
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407

Reference:
Lira AFA, Gonzalez-Santillan E, editors. The Biology of Neotropical Scorpions. From Taxonomy and Genetics to Ecology and Ethnobiology: Springer; 2026. [The book is available in an electronic version or in a printed version, but both require payment or subscription]

Brazilian scorpions in the international pet trade

 

Scorpions are popular pets in many countries. Especially popular are the large members of the family Scorpionidae from Africa and Asia. There is also an increasing interest in species from other families and from other regions.

Brazil has a strict regulation prohibiting collection and export of wildlife, including scorpions. However,  recent study by Kenay Vinicius Lopes de Andrade and Andre Felipe de Araujo Lira shows that several species from five genera from Brazil are available in the international pet trade. Especially worrying is that several medical important species from the genera Tityus C. L. Koch, 1836 and Atreus Gervais, 1843* are represented in the pet trade.

The results are based on surveying social media platforms, and the article discuss the consequences of the illegal import and what can be done to stop it.

*Previous subgenera in Tityus raised to species status by Prendini, 2026 with 61 species previously in Tityus - Buthidae 2026 will soon show the new taxonomy for Buthidae. 

Abstract:
Background and Research Aims: The global wildlife trade is a major driver of biodiversity loss, yet invertebrates remain largely overlooked in conservation policy and monitoring. Scorpions are ecologically important tropical arthropods, and Brazil harbors one of the world’s richest and most endemic scorpion faunas. Despite national legislation prohibiting the collection and commercialization of native wildlife, the extent of international online trade in Brazilian scorpions remains undocumented. We aimed to identify Brazilian species involved in the exotic pet trade using publicly accessible online data and to evaluate associated conservation and biosecurity concerns. Methods: We conducted systematic searches of public social media platforms and online marketplaces between January 2020 and December 2024 using Portuguese and English keywords related to scorpion trade. Posts explicitly indicating possession or sale were recorded, including species identity, country, year, and price when available. Results: We compiled 69 records involving nine species across five genera. Most posts originated outside Brazil, particularly in Europe and North America. Medically significant species, including Tityus serrulatus, Tityus stigmurus, and Atreus obscurus, were repeatedly detected. Records spanned more than a decade, indicating persistent international circulation, with only 26% of records including a price, and given prices ranging between US$12 and US$200. Conclusion: Brazilian scorpions are recurrently present in international online trade, representing an overlooked pathway for the circulation of tropical wildlife. Implications for Conservation: Digital trade exposes enforcement gaps and may contribute to unregulated extraction, biosecurity risks, and neglected pressures on tropical invertebrate biodiversity. Integrating invertebrates into wildlife trade monitoring is urgently needed.

Reference:
Lopes de Andrade KV, Lira AFdA. International Online Trade of Brazilian Scorpions: An Overlooked Threat to Tropical Biodiversity. Tropical Conservation Science. 2026;19:1–8. [Subscription required for full text]

Thanks to Andre Lira for keeping me updated on his publications! 

Sex differences in morphology cause sex differences in stridulation in the buthid Jaguajir rochae

 

It is not that well known that scorpions can produce sound that probably is meant to function defensively as an anti-predator defense. The sound is often called stridulation, and in scorpions it can be produced by morphological structures on the chelicera, legs, cauda or pectines.

Welton Dionisio-da-Silva and co-workers have recently published a study on stridulation Jaguajir rochae (Borelli, 1910) (Buthidae) and any sex-differences in the morphology of the sound producing structures and the acoustic output.

They found that there were several differences in the morphology of the sound producing structures of the pectins between the sexes, and they also found that females produced longer and more intense signals while the males exhibited slightly higher peak frequencies.

Abstract:
Stridulation, acoustic communication produced by friction between specialized body structures, is a poorly studied antipredator mechanism. Scorpions may display multiple defensive responses, yet acoustic signaling in such defensive context remains poorly studied. Given the sexual dimorphism commonly observed in scorpion body size and pectines, the latter, which may be involved in sound production, could vary morphologically and result in acoustic differences. We hypothesized that (1) stridulatory apparatus of the scorpion Jaguajir rochae (Borelli, 1910) is sexually dimorphic, (2) sexual dimorphism in stridulatory structures affects acoustic parameters, and (3) stridulatory responses vary with stress, tested via (2.1) mechanical and (2.2) mechano-chemical stimulation. Sound-producing structures and acoustic parameters were measured and stridulation was tested under high/low mechanical stress and mechano-chemical stress, the latter using chemical cues from a mammalian predator. Females exhibited larger pectinal structures, whereas males showed a higher allometric ratio relative to body size. Stridulatory signals in J. rochae showed sexual differentiation primarily in delta time, dB Sound Pressure Level, and low frequency, as revealed by Principal Component Analysis, what explains 38.7% of acoustic variance. Females produced longer and more intense signals, whereas males exhibited slightly higher peak frequencies. Yet, the occurrence of stridulatory responses was similar across different stress treatments. These findings reveal that sexual dimorphism in stridulatory apparatus influences acoustic parameters and that stridulation in J. rochae can be triggered by mechanical stimulation, supporting its role as a defensive behavior. This study provides the first evidence of sex specific acoustic variation in scorpion stridulation and elucidates its function as an antipredator strategy.

Reference:
Dionisio-da-Silva W, Luna NMC, da Rocha PA, Willemart RH, daSilva MB. She Doesn't Whisper: Female-Prominent Stridulation Shaped by Morphology in a Buthid Scorpion and Insights on Its Function. Ethology. 2026;First published 25.05.26. [Open Access]

Two new chactid species from Northernmost Brazilian Amazon

 

Andre Lira has co-workers have recently published an article describing two new species in the family Chactidae from the Northernmost Brazilian Amazon.

Brotheas cernii Lira, Gonzalez-Santillan, Santos-da-Silva, Brescovit & Pucca, 2026

Cayooca puchus Lira, Gonzalez-Santillan, Santos-da-Silva, Brescovit & Pucca, 2026

The genus Cayooca Gonzalez-Sponga, 1996 has been synonymized with Broteochactas Pocock, 1893. In the recent mega-revision of scorpion taxonomy, Prendini, 2026 resurrected this genus. As previously mentioned, I'm in the process of mapping all changed made in the Prendini paper and decide how to include these in The Scorpion Files. However, because a new species has been described in Cayooca, I have chosen to include this genus as valid in The Scorpion Files. A consequence of this is that Cayooca venezuelensis Gonzalez-Sponga, 1996 is returned to its original genus from Broteochactas Pocock, 1893.

Abstract:
Amid an ongoing environmental crisis marked by high deforestation rates in the Brazilian Amazon, two new species of chactid scorpions are herein described. Cayooca puchus sp. n. is described from an inselberg in the municipality of Mucajaí, state of Roraima, northern Brazilian Amazon. The new species resembles Cayooca venezuelensis but differs by denser body granulation and strongly costate, scattered granular ventromedian and ventral prosubmedian carinae. Brotheas cernii sp. n., described from the same locality, resembles Brotheas granulatus and B. subgranulatus but differs by smaller body size, granular ventral carinae on metasomal segment I, strongly granular pedipalp chelae, and spinoid granules on ventral metasomal carinae of segments III–V. These findings reinforce the Amazon as a major center of biodiversity and highlight the likelihood that numerous species remain undescribed.

Reference:
Lira AFA, González-Santillán E, Santos-da-Silva AP, Brescovit AD, Melo-dos-Santos G, Rocha AM, et al. Two New Species of Scorpions (Scorpiones: Chactidae) from Northernmost Brazilian Amazon. Diversity. 2026;18(6):345. [Open Access]

Thanks to Andre for sending me their article!

Family Chactidae 

Cave and subterranean dwelling scorpions in Brazil

 

As many other invertebrates, som scorpions have adapted to a life in caves and/or in subterrean habitats. A few are true troglobites, adapted to cave life only (often with several troglomorphic adaptions). Others are troglophiles or trogloxenes, living both inside and outside the subterranean realm. 

Jonas Gallao and co-workers have recently published a review summing up the knowledge of cave and subterranean scorpions in Brazil. They found that three families and at least 33 species have been reported from these kinds of habitats. 

Abstract:
Arachnids have successfully colonized subterranean environments. Compared to spiders, harvestmen, and pseudoscorpions, scorpions have a moderate number of subterranean species, including troglophiles and troglobites. Among the four families and 184 species and three subspecies of scorpions found in Brazil, three families and at least 33 species and one subspecies have been documented in subterranean habitats. This study presents a faunistic list of scorpion occurrences in caves and other types of subterranean habitats in Brazil, along with distribution maps and an attempt to classify species based on their use of and dependence on subterranean environments.

Reference:
Gallao JE, Lenhare BD, Oliveira-Neto M, Bichuette ME. Scorpions in Brazilian caves and other subterranean habitats. Euscorpius. 2026(430):1–12. [Open Access] 

Ecological and social contexts of scorpion stings in Manaus, Brazil

 

Scorpionism is a well known problem in Brazil and also in many urban areas. In a recent article, Zehev Benzaken and co-workers have a more original focus on the occurrence and impact of scorpion stings in Brazil. 

They present the results from 30 interviews with sting victims and field observations of where the sting accidents happened. It is very interesting to read how the sting victims experienced the scorpion sting and how they reacted afterward. Also, the study shows that the structural conditions of households and the unplanned expansion of urban areas over natural environments are key factors in understanding the occurrence of scorpion stings.  

The study is an important contribution to finding ways to prevent scorpion accidents in areas where humans have moved into scorpion habitats. 

Abstract:
Scorpion stings remain a significant public health problem in tropical regions, particularly in Brazil, where an estimatied 117,185 cases are reported annually, reflecting a persistent and growing burden on the healthcare system. Globally, more than two million cases occur each year, especially in areas undergoing environmental disturbances such as deforestation and unplanned urbanization. This study investigates the ecological and social contexts of scorpion stings in Manaus, the largest metropolis of the Brazilian Amazon. This qualitative study was conducted at the Dr. Heitor Vieira Dourado Tropical Medicine Foundation (FMT-HVD), a reference center for scorpion stings, between January 2020 and March 2025. Data were collected through clinical questionnaires, indepth interviews, and household field observations. Thematic analysis was performed using Atlas.ti. Thirty participants from different age groups were included. Most cases were clinically mild. Five themes emerged from the qualitative analysis that address perceptions and reactions to the sting, environmental risk factors, postaccident behaviors, emotional impacts, and patient care pathways. Participants reported overlap between domestic spaces and forest fragments, limited knowledge about prevention, emotional distress, and barriers to accessing care, including late referrals and transportation difficulties. Scorpion stings in the Amazon are shaped by environmental, social, and structural factors. Integrated strategies involving environmental management, health education, urban planning, and improved healthcare access are essential to reduce their burden.

Reference:
Benzaken ZS, Cristino JS, Benzaken H, Sachett J, da Silva Carvalho E, da Silva Mendes Y, et al. Ecological and Social Contexts of Scorpion Stings in Manaus, the Largest Metropolis of the Brazilian Amazon. Toxicon. 2026:109122. [Open Access]

The effects of insecticide-contaminated prey on predatory behavior in the scorpion Tityus pusillus

 

Pesticides are commonly used in the fight against "pest-insects" like cockroaches. This can be harmful for other animals, like the predators eating these pesticide-contaminated prey and nature in general. Thayna Rhayane de Brito-Almeida and co-workers have recently published an article investigating the effects of insecticide-contaminated prey on predatory behavior in the scorpion Tityus pusillus  Pocock, 1893 (Buthidae).

The study shows that the acceptance rate prey exposed to insecticides was the same as for prey in the control group. However, there were some modifications in the prey capture behavior in the insecticide group compared to the control group. Also, scorpions that had ingested prey exposed to one type of insecticides showed signs of intoxication, but these were very short lived. It seems that Tityus pusillus is resistant to the insecticides tested.

Abstract:
In many countries, insecticide application in cities is the primary method used for urban pest control. However, the indiscriminate use of these chemical compounds may prejudice native predators which consume contaminated prey. This research aimed to evaluate the behavioural response of Tityus pusillus scorpions to prey previously exposed to different groups of insecticides. Two chemical compounds were tested: pyrethroid cypermethrin spray and the bait-type insecticide indoxacarb, which is an oxadiazine compound. Sixty scorpions were divided into three groups of 20 specimens each: a control group fed on cockroaches not exposed to any insecticide, a pyrethroid group fed on cockroaches previously exposed to cypermethrin, and an indoxacarb group fed on cockroaches exposed to oxadiazine. No difference was detected in prey acceptance among the three groups. Scorpions exposed to oxadiazine showed a non-significant trend toward longer capture latency, while pyrethroid-exposed individuals displayed transient signs of intoxication, with most recovering. Despite these short-term behavioural alterations, scorpions accepted contaminated prey, with no treatment effect on capture latency or acceptance probability. Our findings indicate short-term tolerance to the tested insecticides.

Reference:
Brito-Almeida T, Barbosa de Moura GJ, Lira A. Insecticide-contaminated prey alters predatory behaviour in the scorpion Tityus pusillus (Scorpiones: Buthidae). Arachnology. 2026;20:576–80. [Subscription required for full text]

A new species of Brotheas from Brazilian Amazonia

 

Eric Ythier and Wilson Lourenco recently published an article describing a new species of Brotheas C.L. Koch, 1838  (Chactidae) from Brazilian Amazonia.

Brotheas pseudogranulatus Ythier & Lourenco, 2026

Abstract:
A new species of scorpion, Brotheas pseudogranulatus sp. n. (Scorpiones: Chactidae), is described from the state of Amazonas in Brazil, near the border with Colombia. The new species is notably characterized by a strong granulation over the carapace and tergites, and appears as a possible vicariant element with Brotheas granulatus Simon, 1877, from the Guayana region of South America. The total number of Brotheas species is now raised to 31, of which 14 occur in the Amazon Basin, including 11 from the Brazilian Amazonia. The geographical distribution of the genus Brotheas is also enlarged.

Reference:
Ythier E, Lourenco WR. A new species of Brotheas C. L. Koch, 1838 from Brazilian Amazonia (Scorpiones: Chactidae). Faunitaxys. 2026;14(30):1–7. [Open Access]

Thanks to Eric for informing me about this article!

Family Chactidae 

 

Epidemiology of scorpion envenomations and antivenom use in Brazilian Amazon

 

Scorpion envenomation is a public health problem in many regions of Brazil. Brazil inhabits several dangerous species in the genus Tityus C. L. Koch, 1836 (Buthidae) and several of these are also known to thrive close to human activities or in urban areas. 

Jonas Martins and co-workers have recently published an epidemiological study on scorpion envenomations in Brazilian Amazon between 2010 to 2020. An important part of the study was also to look at the use of antivenoms in the treatment of serious sting cases.

Abstract:
Introduction: Scorpion envenomation in the Amazon causes variable clinical manifestations. Data on these incidents, as well as on the demand, distribution, and use of antivenoms for treatment, are still limited in the literature. This study describes the epidemiology of scorpion envenomation and antivenom coverage in the Legal Amazon area from 2010 to 2020.
Methods: Data on scorpion sting victims, such as sex, age, circumstances of the incident (including location and time), and severity of the case, were obtained from an open health data system called the Notifiable Diseases Information System. The data on antivenom use to treat scorpion stings in each Amazonian state was estimated from consolidated data from the Strategic Inputs Information System.
Results: From 2010 to 2020, 62,388 people were envenomed by scorpions in the Legal Amazon area, resulting in 118 deaths (a fatality rate of 0.19%). The regular distribution of antivenom by the Brazilian Ministry of Health resulted in the allocation of 109,276 vials to the region. However, only 62.2% (of the regional antivenom stockpile 67,994 vials) was used. The state of Pará recorded the highest number of deaths from scorpion stings (33% of total deaths) and the highest use of antivenom per year (∼2705 vials over the 10-y period). Tocantins presented the highest incidence rate, with 119 cases per 100,000 inhabitants.
Conclusion: Although the availability of antivenom in the Legal Amazon between 2010 and 2020 exceeded actual demand, this was not enough to prevent the deaths of 118 victims of scorpion stings. These fatalities primarily affected demographic groups without referral units in their regions and point to critical failures in the spatial distribution of emergency medical services. Rural communities at risk of animal envenomation in the Amazon need timely treatment, a crucial condition for saving lives.

Reference:
Martins JG, Ribeiro de Almeida BR, de Oliveira Pardal PP, de Lima Procópio RE. Scorpion Stings and Antivenom Coverage in the Brazilian Amazon. Wilderness Environ Med. 2026:1–10. [Subscription required for full text]

Thanks to Jonas for sending me this article! 

A phylogenetic analysis of the South American genus Urophonius with the description of a new species

 

Andrés Ojanguren-Affilastro and co-workers recently published a phylogenetic analysis of the genus Urophonius Pocock, 1893 (Bothriuridae) distributed in the southern parts of South America. A new high-altitude species from Chile is described. 

Urophonius andinus Ojanguren-Affilastro & Pizarro-Araya, 2026

 Urophonius is special in that most of the species are active during winter. The evolution of this and the physiological adaptions necessary for winter activities are discussed. 

Abstract:
This study presents the first total evidence dated phylogenetic analysis of the scorpion genus Urophonius, integrating 115 morphological characters and five molecular markers (28S, 18S, H3, 16S, COI). Our comprehensive phylogenetic framework provides novel insights into the genus’ diversification timeline and evolutionary processes. Additionally, we described Urophonius andinus n. sp. from the central Chilean Andes, a high-altitude species found at 2400 m.s.a.l., representing the highest elevational record for the genus. This new species is placed within the granulatus species group, characterized by a spring–summer activity period.

Reference:
Ojanguren‐Affilastro AA, Santibáñez‐López CE, Alfaro FM, Ramírez MJ, Iuri HA, Mattoni CI, et al. First total evidence dated phylogeny of the scorpion genus Urophonius (Bothriuridae), with new insights into the transition to winter activity, and the description of the first highland Andean species of the genus. Systematic Entomology. 2026;51(1):e70032. [Subscription required for full text]

Thanks to Victoria for sharing this article!

Family Bothriuridae 

A new species of Ananteris from French Guiana

 

Eric Ythier and Wilson Lourenco have recently described a new species of Ananteris Thorell, 1891 (Ananteridae) from the foot of the Mount Grand Matoury in French Guiana.

Ananteris duponti Ythier & Lourenco, 2026

The article has am identification key for the Ananteris species in French Guiana. 

The biogeography of the family and the genus is discussed.

Abstract:
One new species belonging to the genus Ananteris Thorell is described from the foot of the Mount Grand Matoury, French Guiana. The description of this new species brings further evidence about the biogeographic patterns of distribution presented by most species of the genus Ananteris, which are highly endemic in many natural formations of South America and in particular in French Guiana. The new taxon described here raises the number of known species for the genus Ananteris in French Guiana to 13, and the total number of currently recognized species for the genus to 100. A geographical distribution map of the species occurring in French Guiana is presented and an identification key is proposed.

Reference:
Ythier E, Lourenco WR. On the genus Ananteris Thorell, 1891 in French Guiana, with description of a new species. Faunitaxys. 2026;14(18):1–12. [Open Access]

Family Ananteridae 

A new cave-dwelling scorpion from Brazil

 

More or less obligatory, cave-dwelling scorpions are found in several areas. Some with distinct troglomorphic traits like reduced pigmentation and the lack of eyes. Jonas Eduardo Gallão and Deyvison Bonfim Ribeiro have recently described a new obligatory, subterranean species in the genus Troglorhopalurus Lourenço, Baptista & Giupponi, 2004 (Buthidae) from three caves in Ituaçu, State of Bahia in Brazil.

Troglorhopalurus araras Gallão & Ribeiro, 2026

The new species lack typical troglomorphic traits except for having thinner cuticle than normal. This may represent a troglomorphic trait.

An identification guide for the genus is presented. Please note that this guide (and article) is missing Troglorhopalurus iuiu Carvalho, Silva, Emanuela de Souza & Feirreira, 2025. According to the authors, the reason for this was that they weren't aware of the description of this species when the paper was submitted. [Info about the missing species updated 02.03.26]

Abstract:
We describe Troglorhopalurus araras sp. n. based only on females, as a new obligatory and exclusively subterranean scorpion occurring in three caves from Ituaçu, State of Bahia, Brazil. The caves of Ituaçu belong to an isolated portion of the Una geomorphological group. Troglorhopalurus araras is the third known species of Troglorhopalurus and differs from its congeners by size, carination mainly in chela hand and metasoma, teeth of pecten, shape of telson spine, and colour. This new species enhances the diversity of cave-dwelling species in Brazilian caves, as well as the knowledge of cave scorpions. Troglorhopalurus araras must be considered threatened due to its restricted endemism at caves in the Chapada Diamantina.

Reference:
Gallão JE, Ribeiro DB. Troglorhopalurus araras (Scorpiones: Buthidae) a new subterranean scorpion from Chapada Diamantina, Bahia, Brazil. Journal of Natural History. 2026;60(9-12):557–72. [Subscription required for full text]

Family Buthidae 

Differences in pedipalp form and size affect courtship behavior in Tityus species

 

Differences in male morphology within the same species have been observed in many species. In a recent paper, Lais Pordeus and Andre Lira show that differences in the male pedipalp chela in Tityus pusillus Lourenço, 2013 (Buthidae) are associated with differences in reproductive behavior. Males with "robust" pedipalp chela performed a higher number of reproductive attempts and female manipulations than than males with "gracile" chela.

Interestingly, the reproductive success of the males in the two groups was quite similar.

Abstract:
This study investigates male pedipalp chela dimorphism and its association with reproductive behaviour in the litter-dwelling scorpion, Tityus pusillus. Using geometric morphometrics, two distinct male morphotypes were identified based on pedipalp chela shape: robust and gracile. These morphotypes were associated with measurable variation in courtship behaviour aspects. Males with robust chelae performed a higher number of reproductive attempts and female manipulations than gracile-chela males, although these differences were not statistically significant. Notably, robust-chela males completed courtship significantly faster than gracile-chelae males (8.03 ± 5.14 minutes vs. 18.40 ± 13.84 minutes), measured as the time until mating successful conclusion. Both morphotypes exhibited similar reproductive success rates (37% and 31%, respectively). These results indicate that robust and gracile differ in courtship dynamics, particularly in courtship duration and patterns of female handling. Variation in female resistance during courtship may help explain why male reproductive behaviours vary. This study documents male chela dimorphism in T. pusillus and reports its correlation with variation in courtship behaviour.

Reference:
Pordeus LM, Lira AFA. Dimorphism in male pedipalps affects the reproductive behaviour in the litter-dwelling scorpion Tityus pusillus Pocock, 1893 (Scorpiones: Buthidae). Invertebrate Reproduction & Development. 2026;Published online 17 Feb 2026. [Subscription required for full text]

How much do people living close to scorpions know about the scorpion’s biology and how to deal with envenomations

 

Scorpions and humans are neighbors in many areas, and this is also the case in many towns and regions in Brazil. This cohabitation will sometimes pose challenges, as scorpions may sting humans and some of them are also quite dangerous. There are many articles dealing with this topic, but few articles have studies the general knowledge local peoples have about scorpion biology and treatment of sting cases.

Luiza Eulália de Azevedo Gonzaga and co-workers published last fall a study where adults locals in a few communities in Brazil were asked to answer a questionnaire about their knowledge about the local scorpion fauna. Interestingly, many of the respondents showed quite good knowledge about the local scorpion's ecological and biological characteristics. Quite a few respondents respected the ecological importance of scorpions, but most of them also admitted fear for this group. More than 70% of them had either been stung or knew about somebody been stung by scorpions. The respondents reported both the use of official medicine (e.g., analgesics) and traditional remedies (the article has a list of these). 

The authors recommend community-based conservation programs that should integrate local knowledge with public health strategies to improve the cohabitation between scorpions and humans.

Abstract:
Scorpions are voracious predators that play crucial roles in maintaining ecological balance within food chains. However, they are also notorious for their venom. Understanding ecological knowledge within local populations helps illuminate the intricate relationship between humans and nature. This study investigates the ecological knowledge and uses of scorpion fauna in three municipalities (Caetés, Cumaru, and Limoeiro) in Pernambuco state, Northeast Brazil—primarily engaged in agricultural activities. We administered a 25-question questionnaire, made available online to adult residents, designed to capture their experiences and perceptions regarding these invertebrates. A total of 121 responses were collected (42 from Caetés, 40 from Limoeiro, and 39 from Cumaru). Results revealed that over 70% of participants had either been victims of scorpion stings or knew someone who had experienced scorpionism. Traditional methods, including substances such as milk, alcohol, ice, and even the scorpion itself, were employed in 33% of cases to treat stings, highlighting gaps in public health education regarding venomous sting management. Respondents classified scorpions within the “insect” ethnocategory and used color to distinguish ethnospecies: yellow, red, and black scorpions. Notably, 88.4% of respondents acknowledged the ecological importance of these creatures, while 79.3% admitted fear of them, yet over 60% recognized their significance for humans. This tension underscores opportunities for community-based conservation programs that integrate local knowledge with public health strategies. The alignment between local perceptions and scientific references suggests potential for integrated approaches to mitigate scorpion-related risks while preserving their ecological roles in agricultural landscapes.

Reference:
de Azevedo Gonzaga LE, de Lima JR, da Silva MA, de Moura GJB, de Araujo Lira AF. Traditional ecological knowledge of scorpions in human communities in a Brazilian semiarid region. International Journal of Tropical Insect Science. 2025;Published 27 November 2025. [Subscription required for full text]

Two papers on the venom and venom effect of Tityus species in Brazil

 

As most of you know, there are several medical important scorpions in the Genus Tityus C. L. Koch, 1836 (Buthidae) in Brazil and other countries of South America. Knowledge of the venom composition of dangerous scorpions and their clinical effect is important, both for understanding how they work, but also to develop effective anti-venom therapy. In addition, studying scorpion venom is also important to see if there are components that can be used in medical research.

Last fall there was published two papers on the biochemistry and the effects of the venom of several species of Tityus (and one species of Brotheas C.L. Koch, 1837 in Chactidae). I refer to the abstracts below for further details on these studies.

Paper 1:

Abstract:
Scorpionism is a growing public health concern in Brazil, with the Amazon region presenting the highest mortality rates but remaining understudied, especially regarding local scorpion venoms composition. This study presents the first comprehensive biochemical characterization of venoms from three Amazonian species—Tityus metuendus (TmetuV), Tityus silvestris (TsilvV), and Brotheas amazonicus (BamazV)—using an integrated approach combining Multi-Enzymatic Limited Digestion (MELD)-based bottom-up proteomics, highresolution LC-MS/MS, chromatography, zymography, and enzymatic assays. Tityus serrulatus venom was included as a reference. Significant biochemical differences were observed: TsilvV was rich in 20–30 kDa proteins and showed strong metalloprotease activity; BamazV exhibited high molecular weight proteins and potent phospholipase A2 (PLA2) activity but lacked proteolytic and fibrinogenolytic activities; TmetuV showed the highest hyaluronidase activity and abundance of α-KTx neurotoxins. Zymography revealed a conserved ~45 kDa hyaluronidase in all species. Three novel components were partially characterized: BamazPLA2 (Group III PLA2), Tmetu1 (37-residue α-KTx), and TsilvMP_A (a metalloprotease homologous to antarease). This is the first application of MELD-based proteomics to Amazonian scorpion venoms, revealing molecular diversity and functional divergence within Tityus and Brotheas, emphasizing the need for region-specific antivenoms. These findings provide a foundation for future pharmacological studies and the discovery of bioactive peptides with therapeutic potential.

Reference:
Bordon KCF, Santos GC, Martins JG, Wiezel GA, Amorim FG, Crasset T, et al. Pioneering Comparative Proteomic and Enzymatic Profiling of Amazonian Scorpion Venoms Enables the Isolation of Their First α-Ktx, Metalloprotease, and Phospholipase A(2). Toxins (Basel). 2025;17(8). [Open Access]

Paper 2:

Abstract:
Scorpion stings are considered a neglected condition and represent a serious health problem in many tropical countries, especially for children and the elderly. In Brazil, the yellow scorpion (Tityus serrulatus) is widely found and responsible for the majority of severe envenoming cases; however, other medically relevant species endemic to the Brazilian Amazon region, such as Tityus silvestris, Tityus metuendus and Tityus obscurus, remain underexplored. In the present study, we characterized the clinical, inflammatory and histopathological responses induced by venoms from these Amazonian species in a murine model (Balb/c mice), using T. serrulatus as a reference. Envenomation with T. silvestris resulted in pronounced systemic manifestations, including elevated clinical scores, hyperglycemia, leukocytosis, cytokine release (IL-6, IL-1β, IL-10), and tissue injury in the lungs and kidneys, comparable to the pathophysiological manifestations from T. serrulatus venom. In contrast, T. metuendus and T. obscurus induced milder inflammatory profiles. It is noteworthy that cross-reactivity assays revealed limited immunoreactivity and reduced in vivo neutralization of T. metuendus and T. obscurus venoms by the commercially available T. serrulatus-based antivenom. These findings reveal critical limitations in relying on a single-species antivenom for treating scorpion envenomation across diverse regions and underscore the need for region-specific therapeutic strategies tailored to the distinct venom profiles and pathogenicity of Amazonian Tityus species.

Reference:
Zoccal KF, de Castro Figueiredo Bordon K, Reis MB, Rosa Nunes de Souza Chini PB, Martins JG, Zuanazzi BA, et al. Divergent clinical, inflammatory, and histopathological responses induced by Amazonian Tityus venoms: insights and limitations of current antivenom therapy. Biochimie. 2025;238(Pt B):159–71. [Subscription required for full text]

Thanks to Jonas Martins for sending me the two articles!

New study on the genus Auyantepuia and two new species from French Guiana

 

16.01.26: New species names are updated with correct year.  

The status of the genus Auyantepuia (Gonzalez-Sponga, 1978) (Chactidae) is controversial and some authors have synonymized the genus with other genera. In the recent years, several authors have accepted the validity of this genus, and The Scorpion Files has now listed the genus and the species originally placed within the genus.

Recently, Eric Ythier and co-workers have published a phylogenomic analysis of the genus Auyantepuia in French Guiana. Current species are diagnosed and two new species are described.

Auyantepuia kwata Ythier, Chevalier, Moreau & Murienne, 2026 

Auyantepuia mammandian Ythier, Chevalier, Moreau & Murienne, 2026 

The article has an identification key for the nine known species in French Guiana.

Abstract:
A review of the scorpions of the genus Auyantepuia (Scorpiones, Chactidae) in French Guiana is conducted using an integrative taxonomic approach combining molecular analysis performed on the mitochondrial genome of most species occurring in the territory and more traditional morphological analyses, leading to the descriptions of two new species, Auyantepuia kwata sp. nov. and Auyantepuia manmandinan sp. nov. Diagnoses are presented for all Auyantepuia species occurring in French Guiana and an identification key is proposed. The total number of recognized species in the genus Auyantepuia species is raised to 15.

Reference:
Ythier E, Chevalier J, Moreau L, Murienne J. A phylogenomic analysis of the genus Auyantepuia (Scorpiones: Chactidae) in French Guiana with the descriptions of two new species. European Journal of Taxonomy. 2026(1034):31–57. [Open Access]

Thanks to Eric for sending me this article!

Family Chactidae