Tityus Species Research Articles

Clinical manifestations and management of Tityus species envenoming: A systematic review

Scorpionism, or a clinical picture of envenomation caused by a scorpion sting, is a public health problem in South America. The manifestations clinical and management are varied and complex and there is still no consensus in the literature on these aspects. The aim of this systematic review is to describe the clinical manifestations, as well as treatment after scorpion envenomation by Tityus species. The online databases of PubMed, Scopus, Web of Science, and SciELO were systematically searched for relevant publications until march 2022. No language and age restrictions were imposed. The literature search generated 476 references and 23 studies were included in the systematic review, according to the inclusion criteria of this review. The number of participants studied was 7,781. The specie Tityus serrulatus was found in more studies. The time elapsed between the accident and medical care ranged from 15 minutes to more than 6 hours. The treatments performed in selected studies include scorpion antivenoms, corticosteroids, anesthetics, antiemetics agents, inotropics, antihypertensives and benzodiazepines drugs. In six studies, fatal cases were observed in five children aged 1 to 6-y and one in children < 14 y. We concluded that management of Tityus species envenoming is supportive and focused on the patient’s symptoms. In severe cases, antivenoms, if available, are indicated. Medications to monitor vagal and adrenergic symptoms are encouraged. This study has the potential to help professionals who deal with envenomations caused by the genus Tityus.

Proteomic profile of the venom of three dark-colored Tityus (Scorpiones: Buthidae) from the tropical rainforests of Costa Rica

ObjectiveWe aimed to elucidate the potential differences in the venom peptide sequences of three Tityus species from Costa Rican rainforests: T. jaimei, T. championi and T. dedoslargos, compared to T. cf. asthenes from Colombia, which could explain the low level of scorpionism in Costa Rica, evidenced by the lack of epidemiological data. MethodologyWe applied venom proteomics of peptides purified by RP-HPLC and compared the obtained sequences from venoms of these Tityus species to the sequences previously identified from Tityus inhabiting other Central and South American regions. ResultsVenom proteome analysis evidences that most of the putative peptide toxins identified in Costa Rican dark-colored Tityus are very similar to those present in other T. (Atreus) from the region. ConclusionsOur study suggests that, in the case of potential envenomation by Tityus in Costa Rica, the same level of toxicity should be observed, compared to other cases caused by members of the subgenus from other geographical localities. On the other hand, compared to countries with more accelerated urban expansion, Costa Rican Tityus still inhabit secondary rainforests and do not commonly share the same spaces with humans, so the lack of epidemiological evidence of medical emergencies caused by envenoming by this scorpion group could be more related to ecological and demographic factors and less attributed to the characteristics of the venom.

A proteomic overview of the major venom components from Tityus championi from Panama

In recent years, morbidity caused by scorpion sting of the species Tityus championi has increased in Panama. Therefore, the LD50 was determined by intravenous injection in 2.9 mg/kg and the venom of T. championi was separated using a HPLC system and their fractions were tested for biological activities in mice to identify the most toxic fractions to mammals. In addition, the venom fractions were also tested against invertebrates to look for insect-specific toxin peptides. The most toxic fractions were analyzed by MS/MS spectrometry. The primary structures of T. championi venom peptides with the most relevant activity were obtained, and the primary structure of one of most neurotoxic peptides was found at least in other four species of Tityus from Panama. This neurotoxin is quite important to be used as a protein target to be neutralized if developing antivenoms against the sting of this Panamanian scorpion or other relevant species of genera Tityus in the country.

Scorpion envenomation in Brazil: Current scenario and perspectives for containing an increasing health problem.

Opportunistic scorpion species can colonize urban environments, establishing high-density communities that enhance the chances of human accidents. This scenario has been taking place in Brazil, in which some Tityus species have taken city centers, causing an explosion in the number of scorpion envenoming cases. The characteristics of this scorpionism epidemic in Brazil is discussed in the present work. The number of Brazilian scorpion stings has surpassed 120,000 cases in 2017, and has been maintained above this number ever since, representing a more than 3-fold increase in 10 years, which was higher than the number of cases for most of the neglected tropical diseases in the country. The escalation in scorpionism cases is even higher in some regions of Brazil. Fortunately, the proportion of mild cases has also increased in the analyzed period, as well as the number of victims seeking for medical attention within the first hour after the accident. The species Tityus serrulatus, Tityus stigmurus, Tityus bahiensis, and Tityus obscurus are traditionally accountable for most of the scorpion accidents in different regions of Brazil, but other species deserve to be closely watched. Despite scorpionism being a notable health problem in Brazil, accident prevention and pest control regarding this venomous animal have not been properly addressed by the scientific community nor by policy makers. Therefore, this review also aims to point possible fields of research that could help to contain the aggravation of the current scorpionism landscape in Brazil.

Kinetic Activity of Chromosomes and Expression of Recombination Genes in Achiasmatic Meiosis of Tityus (Archaeotityus) Scorpions.

Several species of Tityus (Scorpiones, Buthidae) present multi-chromosomal meiotic associations and failures in the synaptic process, originated from reciprocal translocations. Holocentric chromosomes and achiasmatic meiosis in males are present in all members of this genus. In the present study, we investigated synapse dynamics, transcriptional silencing by γH2AX, and meiotic microtubule association in bivalents and a quadrivalent of the scorpion Tityus maranhensis. Additionally, we performed RT-PCR to verify the expression of mismatch repair enzymes involved in crossing-over formation in Tityus silvestris gonads. The quadrivalent association in T. maranhensis showed delay in the synaptic process and long asynaptic regions during pachytene. In this species, γH2AX was recorded only at the chromosome ends during early stages of prophase I; in metaphase I, bivalents and quadrivalents of T. maranhensis exhibited binding to microtubules along their entire length, while in metaphase II/anaphase II transition, spindle fibers interacted only with telomeric regions. Regarding T. silvestris, genes involved in the recombination process were transcribed in ovaries, testes and embryos, without significant difference between these tissues. The expression of these genes during T. silvestris achiasmatic meiosis is discussed in the present study. The absence of meiotic inactivation by γH2AX and holo/telokinetic behavior of the chromosomes are important factors for the maintenance of the quadrivalent in T. maranhensis and the normal continuation of the meiotic cycle in this species.

On the Tityus forcipula species group: redescription of Tityus forcipula (Scorpiones, Buthidae), description of a new Andean species, and notes on the taxonomy of the group.

The Tityus forcipula species group has had an intricate taxonomic history, changing its diagnostic characters and composition on several occasions. One of the alleged reasons for this taxonomic uncertainty is the use of superficial characters (i.e. raw similarity instead of putative synapomorphies) for species group delimitation. Here, we conducted a thorough phenotypic survey across the Tityus forcipula species group, as currently delimited, including characters that had been suggested elsewhere as putative synapomorphies for delimiting lineages within Tityus. In doing so we also redescribe Tityus forcipula and describe a new species belonging to the Tityus forcipula species group: Tityus moralensis sp. nov. based on specimens from the Andean region of Valle del Cauca department, Colombia. The Tityus forcipula species group is here delimited to Andean species from Colombia and Ecuador that share strongly sclerotized and brown colored pectines, basal middle lamellae of female pectines dilated and suboval or ovoid shaped, basal plate of female pectines without glandular region and telotarsi with two ventrosubmedian rows (type II) of stout macrosetae (i.e., Tityus crassicauda, Tityus cuellari, Tityus forcipula, Tityus fuhrmanni and Tityus moralensis sp. nov). The new Tityus species is placed into a phylogenetic context with other buthid species using DNA sequences (COI and 28S). Finally, we provide a map with updated distributional records of the Tityus forcipula species group.

Clinical profile of confirmed scorpion stings in a referral center in Manaus, Western Brazilian Amazon

Scorpion envenomations are a major public health problem in Brazil, and most medically important cases are attributable to the Tityus genus. The objective of this study is to describe the clinical and epidemiological aspects of a series of 151 cases of confirmed scorpion stings, which were treated at the hospitals of two cities in the Western Brazilian Amazon, between June 2014 and December 2019. This study shows that the genus Tityus was the most prevalent. Tityus (Atreus) metuendus (Pocock, 1897) was responsible for the greatest number of cases (68.2%), followed by Tityus (Archaeotityus) silvestris (Pocock, 1897) (14.6%). Most of the envenomations involved males (53.6%), and analysis showed a slight predominance in the group from 40 to 49 years (22.5%). The most affected body regions were feet (49.0%) and hands (31.8%). The time elapsed between the accident and medical care was ≤6 h in 92.1% of cases. Regarding clinical severity, classes I (80.8%) and II (15.9%) predominated. However, there were five (3.3%) class III cases; four for T. metuendus and one for T. silvestris. The most frequent local and systemic manifestations were, respectively, pain (84.1%), paresthesia (34.4%) and mild edema (25.8%), and nausea (9.3%) and myoclonia (8.6%). The clinical manifestations were similar among the patients stung by the different species of scorpions. There were no differences between the manifestations of envenomation caused by T. metuendus, T. silvestris and T. raquelae. For victims of T. apiacas, a higher frequency of piloerection and myoclonia was observed, and was described by the affected patients as a ‘sensation of receiving an electric shock’ throughout the body. No deaths were registered. The species of greatest epidemiological importance in Manaus is T. metuendus, a species that leads to clinical pictures that do not differ substantially from those observed in other Brazilian regions. T. apiacas causes neurological manifestations that differed from other Tityus species. Our findings suggest that the available antivenoms have little effectiveness when used in the treatment of envenomations by some Amazonian scorpions.

Change in the distribution of Tityus species of sanitary importance in Argentina

Change in the distribution of Tityus species of sanitary importance in Argentina

P>Taxonomic revision of the Colombian Tityus (Archaeotityus) (Scorpiones, Buthidae) species: a morphological and morphometric approach, with a description of a new species.

We present a taxonomic revision of the Colombian Tityus (Archaeotityus) species based on morphological and morphometric evidence. We examined more than 385 specimens and evaluated new and previously used qualitative and quantitative morphological characters. We redescribe the Colombian species and present morphological characters for both sexes and an emended diagnosis for the subgenus Tityus (Archaeotityus). We describe a new species Tityus guane sp. nov. from Santander department, Colombia, Tityus betschi Lourenço 1992 is synonymized with Tityus parvulus Kraepelin, 1914, and Tityus wayuu Rojas-Runjaic Armas, 2007 is synonymized with Tityus tayrona Lourenço, 1991. We measured 186 specimens and performed a multivariate principal component analysis (PCA) for 34 selected morphometric ratios for each sex. We found that a few morphological ratios support species level distinctions within the Colombian species. We provide updated distributional maps with new records and an identification key for both sexes. Furthermore, we provide an updated checklist for the subgenus and a discussion about the character systems used within Tityus (Archaeotityus). The new morphological characters proposed and the traditional morphometry examined with a PCA are useful for studying Tityus (Archaeotityus) taxonomy.

Structural and functional characterization of toxic peptides purified from the venom of the Colombian scorpion Tityus macrochirus

The soluble venom of the scorpion Tityus macrochirus was separated by chromatographic procedures and three homogeneous peptides were obtained and their primary structures were determined. They were called: Tma1-Tma3, from the abbreviated name of the scorpion. Tma1 is a peptide containing 65 amino acids with four disulfide linkages and a molecular weight of 7386.2 Da. It is a mammalian toxin, shown to affect human sodium-channels sub-types hNav1.6 and hNav1.4. Tma2 and Tma3 are peptides containing 69 amino acids linked by four disulfide bonds, molecular weights 7819.7 and 7830.0 Da, respectively. They do not affect human sodium-channels but are lethal to insects (crickets). A phylogenic analysis of the three peptides and those of other toxic peptides isolated from the genus Tityus and Centruroides were grouped together and analyzed, permitting to obtain a topology with two main clades, one includes most sodium-channel anti-insect scorpion toxins and others includes mostly sodium-channel scorpion toxins anti-mammalian. Tma1 segregates among a group of well-studied β-class toxins of other Tityus species such as T. discrepans, T. obscurus and T. pachyurus. Tma2 and Tma3 are associated with anti-insect toxins, particularly with one of T. obscurus. This phylogenetic analysis confirms and enforces our experimental results obtained with these three new sodium-channel scorpion toxins.

El Accidente por Escorpiones Tóxicos en el Paraguay: Mito y Realidad en el contexto de la Emergencia por Escorpionismo en el Sudeste de la América del Sur

El escorpionismo, como se conoce al accidente producido por escorpiones tóxicos en humanos, es un problema de salud pública en varias regiones del mundo, incluyendo centros urbanos de la América Tropical. La elevada toxicidad de algunas de las especies del género Tityus ha demandado la preparación de antivenenos específicos en América Latina, única estrategia terapéutica eficaz para el tratamiento de estos accidentes. En Paraguay habitan tres especies del género (T. trivittatus, T. confluens y T. bahiensis) de reconocida peligrosidad en Argentina y Brasil, pero cuya real importancia sanitaria en el país es desconocida. Ante el registro de accidentes severos y el posible escenario de un incremento epidemiológico del escorpionismo en Paraguay producto del calentamiento global, esta revisión presenta las especies conocidas del país, su distribución y datos sobre su toxicidad, a fin de sentar las bases para un necesario estudio que aclare la real magnitud del problema en el país e identifique los antivenenos antiescorpiónicos efectivos en Paraguay.

Study on the obtaining of Tityus trivittatus venom in Argentina

Envenomation by scorpions of the genus Tityus is an important public health problem in Argentina, involving near 8000 stings and 2 deaths each year. Treatment for envenomation is the use of specific antivenom and intensive hospital care. Antivenom is produced by the Ministry of Health and freely distributed throughout the country. For antivenom production it is necessary to collect scorpion venom, which is a difficult task because although scorpions can be found in Argentina, they are less abundant than in warmer latitudes. For this reason venom collection constitutes a bottleneck for antivenom production. Although in Argentina several species of Tityus can be found, most of the accidents are caused by Tityus trivittatus, and the venom of this scorpion has historically been the venom used for antivenom production. We analyzed retrospectively 26 pools of telson homogenates (6964 telsons) and 37 pools of milked venom obtained by electrical stimulation (equivalent to 6841 milkings). Lethal potencies of samples from different provinces were very similar, although venom from scorpions of Buenos Aires city showed the lowest potency. The venom obtained by milking (median LD50 12.3 μg), provided batches containing LD50s more potent when compared with the venom obtained from telson homogenates (p < 0.0001). Many batches of telson homogenates (30%) showed lower potencies than acceptable for antivenom production and control. In addition to the study of the venom yield, the records of immunization of horses, the potency of the batches and the protein content of each batch of anti-scorpion antivenom produced were analyzed, comparing those produced using milked venom with those using telson homogenates as immunogens. Batches produced using milked venom required a shorter period of immunization (p < 0.0001), rendered higher neutralizing titers (p 0.0350) and possessed lower protein content (p 0.0092). Results clearly showed that the milking of scorpions is a more efficient tool to obtain venom for antivenom production in comparison to the use of telson homogenates.

Especies de importancia médica de Tityus (Scorpiones; Buthidae) en la Argentina

especies de importancia médica de Tityus (Scorpiones; Buthidae) en la Argentina

Potential effects of climate change on the risk of accidents with poisonous species of the genus Tityus (Scorpiones, Buthidae) in Argentina

The temporal pattern of co-occurrence of human beings and venomous species (scorpions, spiders, snakes) is changing. Thus, the temporal pattern of areas with risk of accidents with such species tends to become dynamic in time. We analyze the areas of occurrence of species of Tityus in Argentina and assess the impact of global climate change on their area of distribution by the construction of risk maps. Using data of occurrence of the species and climatic variables, we constructed models of species distribution (SMDs) under current and future climatic conditions. We also created maps that allow the detection of temporal shifts in the distribution patterns of each Tityus species. Finally, we developed risk maps for the analyzed species. Our results predict that climate change will have an impact on the distribution of Tityus species which will clearly expand to more southern latitudes, with the exception of T. argentinus. T. bahiensis, widely distributed in Brazil, showed a considerable increase of its potential area (ca. 37%) with future climate change. The species T. confluens and T. trivittatus that cause the highest number of accidents in Argentina are expected to show significant changes of their distributions in future scenarios. The former fact is worrying because Buenos Aires province is the more densely populated district in Argentina thus iable to become the most affected by T. trivittatus. These alterations of distributional patterns can lead to amplify the accident risk zones of venomous species, becoming an important subject of concern for public health policies.

Proteomic endorsed transcriptomic profiles of venom glands from Tityus obscurus and T. serrulatus scorpions.

BackgroundExcept for the northern region, where the Amazonian black scorpion, T. obscurus, represents the predominant and most medically relevant scorpion species, Tityus serrulatus, the Brazilian yellow scorpion, is widely distributed throughout Brazil, causing most envenoming and fatalities due to scorpion sting. In order to evaluate and compare the diversity of venom components of Tityus obscurus and T. serrulatus, we performed a transcriptomic investigation of the telsons (venom glands) corroborated by a shotgun proteomic analysis of the venom from the two species.ResultsThe putative venom components represented 11.4% and 16.7% of the total gene expression for T. obscurus and T. serrulatus, respectively. Transcriptome and proteome data revealed high abundance of metalloproteinases sequences followed by sodium and potassium channel toxins, making the toxin core of the venom. The phylogenetic analysis of metalloproteinases from T. obscurus and T. serrulatus suggested an intraspecific gene expansion, as we previously observed for T. bahiensis, indicating that this enzyme may be under evolutionary pressure for diversification. We also identified several putative venom components such as anionic peptides, antimicrobial peptides, bradykinin-potentiating peptide, cysteine rich protein, serine proteinases, cathepsins, angiotensin-converting enzyme, endothelin-converting enzyme and chymotrypsin like protein, proteinases inhibitors, phospholipases and hyaluronidases.ConclusionThe present work shows that the venom composition of these two allopatric species of Tityus are considerably similar in terms of the major classes of proteins produced and secreted, although their individual toxin sequences are considerably divergent. These differences at amino acid level may reflect in different epitopes for the same protein classes in each species, explaining the basis for the poor recognition of T. obscurus venom by the antiserum raised against other species.

Insights into the origin of the high variability of multivalent-meiotic associations in holocentric chromosomes of Tityus (Archaeotityus) scorpions.

Scorpions represent an intriguing group of animals characterized by a high incidence of heterozygous chromosomal rearrangements. In this work, we examined six species of Tityus (Archaeotityus) from Brazilian fauna with a particular focus on elucidating the rearrangements responsible for the intraspecific variability of diploid number and the presence of long chromosomal chains in meiosis. To access any interpopulation diversity, we also studied individuals from four species representing distinct localities. Most species demonstrated intraspecific polymorphism in diploid number (2n = 19 and 2n = 20 in T. clathratus, T. mattogrossensis, and T. pusillus, 2n = 16, 2n = 17 and 2n = 18 in T. paraguayensis, and 2n = 16 and 2n = 24 in T. silvestris) and multi-chromosomal associations during meiosis I, which differed even among individuals with the same chromosome number. In some species, the heterozygous rearrangements were not fixed, resulting such as in Tityus clathatrus, in 11 different chromosomal configurations recognized within a same population. Based on meiotic chromosome behaviour, we suggested that independent rearrangements (fusion/fission and reciprocal translocations), occurring in different combinations, originated the multi-chromosomal chains. To evaluate the effects of these chromosome chains on meiotic segregation, we applied the chi-square test in metaphase II cells. The non-significant occurrence of aneuploid nuclei indicated that non-disjunction was negligible in specimens bearing heterozygous rearrangements. Finally, based on our analysis of many chromosome characteristics, e.g., holocentricity, achiasmate meiosis, endopolyploidy, ability to segregate heterosynaptic or unsynapsed chromosomes, (TTAGG)n sequence located in terminal regions of rearranged chromosomes, we suggest that the maintenance of multi-chromosomal associations may be evolutionarily advantageous for these species.

Venoms of Centruroides and Tityus species from Panama and their main toxic fractions

The scorpionism in Panama is notorious for the confluence and coexistence of buthid scorpions from the genera Centruroides and Tityus. This communication describes an overview of the larger representative toxic venom fractions from eight dangerous buthid scorpion species of Panama: Centruroides (C. granosus, C. bicolor, C. limbatus and C. panamensis) and Tityus (T. (A.) asthenes, T. (A.) festae, T. (T.) cerroazul and T. (A.) pachyurus). Their venoms were separated by HPLC and the corresponding sub-fractions were tested for lethality effects on mice and insects. Many fractions toxic to either mice or insects, or both, were found and have had their molecular masses determined by mass spectrometry analysis. The great majority of the lethal components had a molecular mass close to 7000 Da, assumed to be peptides that recognize Na+-channels, responsible for the toxicity symptoms observed in other buthids scorpion venoms. A toxic peptide isolated from the venom of T. pachyurus was sequenced by Edman degradation, allowing the synthesis of nucleotide probe for cloning the correspondent gene. The mature toxin based on the cDNA sequencing has the C-terminal residue amidated, contains 62 amino acid packed by 4 disulfide linkages, with molecular mass of 7099.1 Da. This same toxic peptide seems to be present in scorpions of the species T. pachyurus collected in 5 different regions of Panama, although the overall HPLC profile is quite different. The most diverse neurotoxic venom components from the genus Centruroides were found in the species C. panamensis, whereas T. cerroazul was the one from the genus Tityus. The most common neurotoxins were observed in the venoms of T. festae, T. asthenes and T. pachyurus with closely related molecular masses of 7099.1 and 7332 Da.The information reported here is considered very important for future generation of a neutralizing antivenom against scorpions from Panama. Furthermore, it will contribute to the growing interest in using bioactive toxins from scorpions for drug discovery purposes.

Many unique characteristics revealed by the complete mitochondrial genome of the scorpion Tityus serrulatus (Lutz e Mello 1922) (Chelicerata; Arachnida)

This is the first complete mitochondrial genome of a Tityus species, although it is the most medically important genus in South America. Tityus serrulatus (Brazilian yellow scorpion) mtDNA revealed the same gene arrangement of three out of four other mitogenomes published by now for the same family (Centruroides limpidus, Mesobuthus gibbosus, M. martensii and Buthus occitanus). However, it presented many unique characteristics such as possession of Cox1 gene, different from all other protein-coding genes of scorpion mtDNA, starts with an atypical start codon (CTG). Moreover, no tRNA gene have complete typical secondary structure and the Tytius genome presented three non-coding regions longer than 100bp. Also, it contains the smallest scorpion 16S gene reported by now. Phylogenetic analysis using concatenated homologous genes confirmed Buthidae as a monophyletic clade and supports a monophyletic group including T. serrulatus and the other American species, C. limpidus.

Two new scorpions from the Puerto Rican island of Vieques, Greater Antilles (Scorpiones: Buthidae)

Two new scorpion species of the family Buthidae are described herein: Microtityus vieques sp. n. (a member of the subgenus Parvabsonus Armas, 1974) and Tityus alejandroi sp. n. (belonging to the “quisqueyanus” species-group). Both were collected from pitfall traps in the Puerto Rican satellite island of Vieques, in the Greater Antilles, and the former represents the first official record of the occurrence there of the gens Microtityus Kjellesvig-Waering, 1966. As expected, the new species have their closest relatives in Puerto Rico. Fully illustrated descriptions and detailed comparisons are provided. Additionally, two other Puerto Rican species of Tityus currently not assigned to any group are herein formally transferred to the “quisqueyanus” species group: Tityus angelesae Santiago-Blay, 2009 and Tityus juliorum Santiago-Blay, 2009. After this contribution, the scorpion fauna of Puerto Rico is now com-posed of 19 species.

The remarkable scorpion diversity in the Ecuadorian Andes and description of a new species of Tityus C. L. Koch, 1836 (Scorpiones, Buthidae).

A new species of Tityus, subgenus Atreus (Scorpiones: Buthidae) is described from the Province of Pichincha in the Ecuadorian Andes. Ecuadorian scorpion fauna remains one of the less well studied among those of South America. Nevertheless, some comments are addressed about its remarkable diversity and high level of endemic elements.