First DNA barcode records for the buthid Parabuthus liosoma in Saudi Arabia.

 

Ahmed Badry and co-workers recently published a study of DNA barcoding and phylogeny of Parabuthus liosoma (Ehrenberg, 1828) (Buthidae) from Saudi Arabia. This is the first DNA barcode records for this species, and the study gives insight into identification, taxonomy and phylogeny of Parabuthus in Saudia Arabia.

Abstract:
1) Background. Parabuthus liosoma is one of the largest buthid scorpion species and is endemic to Saudi Arabia and Yemen. This study provides the first DNA barcoding and phylogenetic analysis of P. liosoma from Saudi Arabia, contributing to global efforts in arachnid molecular identification and biodiversity documentation. (2) Methods. The whole genome was extracted from nine adult individuals of P. liosoma, collected from Farasan Island, southwest of Saudi Arabia. A portion of the mitochondrial DNA, specifically, the cytochrome oxidase subunit I gene (COI) sequences, was amplified and sequenced and subjected to genetic and phylogenetic analyses. (3) Results. The DNA barcoding results revealed a high level of genetic variability within P. liosoma, aiding in species identification and supporting its utility as a molecular tool for scorpion taxonomy. In addition, our results reveal a monophyletic relationship among Parabuthus species, with a clear distinction between Arabian and African lineages. (4) Conclusions. This study highlights the effectiveness of DNA barcoding as a reliable tool for species identification and taxonomy and enhances our knowledge of the evolutionary history and geographic distribution of Parabuthus scorpions. However, further research is required to elucidate the complex phylogenetic relationships within this genus.

Reference:
Badry A, Al-Qahtni AH, Al-Salem AM, Al Balawi MS, Mesfer F, Allahyani WS, et al. DNA Barcoding and Phylogenetic Relationship of Parabuthus liosoma (Ehrenberg, 1828) (Scorpiones: Buthidae) in Saudi Arabia. Biology. 2026;15(4):321. [Open Access]

Thanks to  Luis Roque (Arácnido Taxonomy https://www.aracnidotaxonomy.com) for sending me this article!

Family Buthide 

Pregnant woman stung by Parabuthus maximus in Kenya

 

I usually do not blog all scorpion envenomation reports, but I found this one of special interest as the victim was a pregnant women and the case involved a Parabuthus Pocock, 1890 (Buthidae) species from Kenya. We know quite a lot about the consequences of Parabuthus envenomations from southern Africa, but there are fewer documented cases from East Africa.

Felix Pius Omullo recently published a case report involving a 36 week pregnant women stung by a confirmed Parabuthus maximus Werner, 1913 (Buthidae) in Kenya. Thanks to quick treatment and administration of species-specific antivenom, both the mother and the fetus improved quickly. Both mother and the baby were well two weeks after the baby was born. 

The article discusses the case and the interventions necessary in cases like this.

PS! The dark discoloration shown in the picture of the sting site on the heel is due to traditional medicine first aid using a pasty substance made of a mixture of Kiwi shoe polish and Colgate toothpaste.

Abstract:
BACKGROUND
Scorpion envenomation in pregnancy is a rare but potentially fatal obstetric emergency, with limited evidence on optimal management and antivenom safety. Neurotoxic venom induces autonomic storms, threatening maternal cardiovascular stability and uteroplacental perfusion, which can lead to fetal distress or demise.

CASE SUMMARY
A 31-year-old gravida 4, para 3 woman at 36 weeks’ gestation presented 30 minutes after a confirmed Parabuthus maximus sting to her right foot. She manifested systemic envenomation, including agitation, profuse sweating, tachycardia (142 bpm), and hypertension (168/102 mmHg). Cardiotocography revealed fetal tachycardia (175-180 bpm). A multidisciplinary team initiated intravenous morphine, midazolam, and species-specific antivenom (South African Vaccine Producers Polyvalent Scorpion Antivenom), resulting in the resolution of maternal and fetal symptoms within 12 hours. Critically, antivenom was administered within 40 minutes of the sting, which likely contributed to the rapid reversal of the catecholamine surge. A key factor enabling this rapid and targeted response was the patient’s action of capturing the scorpion, allowing for precise species identification. The pregnancy progressed uneventfully to term, culminating in an uncomplicated vaginal delivery of a healthy infant.

CONCLUSION
This case illustrates that scorpion envenomation in late pregnancy poses a dual threat to both maternal and fetal well-being. Prompt recognition, continuous fetal monitoring, and the very early administration of antivenom-buttressed by multidisciplinary care-can avert catastrophic outcomes. This case provides supporting evidence that antivenom can be safe and effective during the third trimester, even in resource-constrained environments. Public education on safe first aid, including bringing the scorpion for identification, is essential.

Reference:
Omullo FP. Successful management of third-trimester scorpion envenomation (Parabuthus maximus) in a resource-limited setting: A case report. World J Clin Cases. 2026;14(2):114762. [Open Access]

An updated look at scorpion envenomations in Namibia

 

Scorpion envenomations and their medical importance in Namibia have been underreported and neglected. Namibia is the home for several Parabuthus Pocock, 1890 (Buthidae) species, a genus known for hosting several species of medical importance.

Francois Theart and co-workers recently published an article with updated information about scorpionism in Namibia. They conclude that scorpions are a health concern in this country and especially the species Parabuthus granulatus (Ehrenberg, 1831), P. villosus (Peters, 1862), kraepelini Werner, 1902 and P. schlechteri Purcell, 1899 can cause death and serious morbidity. No antivenom is available. More research is necessary to understand more about the situation and to develop measures to improve prevention and treatment.

Abstract:
Namibia harbours a rich diversity of scorpions, including seventeen species of the highly venomous genus Parabuthus, although the biology and medical relevance of most species are poorly documented. Severe envenoming is caused by at least P. granulatus, P. villosus, P. kraepelini and P. schlechteri, which are considered to be of particular importance. Data on epidemiology, venom composition and variation, and clinical effects remain scarce. A lack of effective antivenom and long distances to hospitals in rural areas complicate clinical management and compromise patient outcomes.

Reference:
Theart F, Buys C, Lagneau S, Berg P. Scorpion envenoming by Parabuthus is a public health concern in Namibia. Toxicon. 2025;270:108934. [Subscription required for full text]

New cases of anatomical malformations in scorpions

  

There have been quite a few articles documenting anatomical malformations in scorpions (teratology). In a recent article, Danniella Sherwood and co-workers document three more cases of anatomical malformations in a Lychas C.L. Koch, 1845 species from Australia and Parabuthus raudus (Simon, 1888) from Botswana (both Buthidae).

Abstract:
Three cases of tergite malformation are described: two in Parabuthus raudus (Simon, 1888) from Botswana and one in Lychas sp. from Australia. One adult female P. raudus had tergite IV almost split into two parts, an anomaly that also affected tergites II–III. In another female P. raudus, a longitudinal depression presented across tergites I–IV. In Lychas sp., tergites I–II are strongly constricted transversely, exposing the adjacent pleural membrane dorsally.

Reference:
Sherwood D, Jessnitz V, Tang V. Three more cases of tergite malformation in two buthid scorpion species revealed from citizen science data (Scorpiones: Buthidae). Revista Iberica de Arachnologia. 2025(46):135–7. [Full text available by authors]

Thanks to Danniella for sending me their article!

A new species of Parabuthus from Ethiopia

 

Frantisek Kovarik and Hassan Elmi published this week a new species in my favorite genus Parabuthus Pocock, 1890 (Buthidae) from Ethiopia.

Parabuthus qaraaf Kovarik & Elmi, 2025

A map showing the distribution of the 19 known Parabuthus species from The Horn of Africa is also presented.

Abstract:
A new species Parabuthus qaraaf sp. n. from Ethiopia is described. Combination of six characters: metasoma V black; pectine teeth number 33–42 in both sexes; pedipalp chela length/ width ratio 3.3 in male and 4.2 in female; pedipalp patella length/ wide ratio 2.36–2.38 in both sexes; fingers of pedipalp of male with inner side of base smooth, no trace of tubercle; metasoma V length/ wide ratio is 1.50 in male distinguish P. qaraaf sp. n. from all other species in the region. Included is also a map of distribution of Parabuthus species in Horn of Africa, with newly confirmed localities for Parabuthus granimanus Pocock, 1895 and P. robustus Kovařík et al., 2019.

Reference:
Kovarik F, Elmi HSA. Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XLII. Parabuthus qaraaf sp. n. from Ethiopia (Buthidae). Euscorpius. 2025(419):1–11. [Open Access]

Family Buthidae

A new species of Parabuthus from Somalia (Puntland)

 

Frantisek Kovarik and his co-workers are continuing their tireless work on the scorpion fauna of The Horn of Africa. Recently, they have published a new article describing a new species of Parabuthus Pocock, 1890 (Buthidae) from Somalia (Puntland).

Parabuthus puntlandus Kovarik, Stahlavsky, Elmi & Starha, 2025

Abstract:
A new species Parabuthus puntlandus sp. n. from Somalia (Puntland) is described. Combination of five characters; metasoma V black; pectine teeth number 39–42 in both sexes; pedipalp chela length/width ratio 3.05–4.26 in both sexes; metasoma and telson sparsely hirsute; smooth inner side of the base of fingers of pedipalp chela (tubercle absent) distinguish P. puntlandus sp. n. from all other species in the region. In addition to the analyses of external morphology, we have provided descriptions of the karyotype of P. puntlandus sp. n. (2n=16). Included is also a map of distribution of Parabuthus species in Horn of Africa.

Reference:
Kovarik F, Stahlavsky F, Elmi HSA, Starha R. Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XXXVIII. Parabuthus puntlandus sp. n. from Somalia (Puntland) (Buthidae). Euscorpius. 2025(414):1–11. [Open Access]

Family Buthidae

A new species of Parabuthus from Somalia

 

Frantisek Kovarik just published the description of a new species of Parabuthus Pocock, 1890  (Buthidae) from Somalia (Puntaland).

Parabuthus starhai Kovarik, 2025

Abstract:
A new species Parabuthus starhai sp. n. from Somalia (Puntland) is described. Combination of two characters, pectine teeth number 56–59 in both sexes and pedipalp chela length/ width ratio 3.65 in male and 5.47 in female differ P. starhai sp. n. from all other species in the region. Included is also a map of distribution of Parabuthus species in Horn of Africa.

Reference:
Kovarik F. Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XXXV. Parabuthus starhai sp. n. from Somalia (Puntland) (Buthidae). Euscorpius. 2025(405):1-10. [Open Access]

Family Buthidae

Three new species of Parabuthus from Somaliland

 

In part 30 of their ongoing series "Scorpions of the Horn of Africa", Frantisek Kovarik and co-workers describe three new species of Parabuthus Pocock, 1890 (Buthidae) from Somaliland. 

Parabuthus dorisae Kovarik, Lowe, Elmi & Stahlavsky, 2024

Parabuthus evae Kovarik, Lowe, Elmi & Stahlavsky, 2024

Parabuthus quincyae Kovarik, Lowe, Elmi & Stahlavsky, 2024

The true distribution of Parabuthus eritreaensis Kovarik, 2003 is discussed and a distribution map for all species in the Horn of Africa is included. 

Abstract:
A new record of an adult female of Parabuthus eritreaensis Kovařík, 2003 in Somaliland confirms true distribution of this species, already discussed in Kovařík et al. (2016: 19–21). Three new species are described from Somaliland, P. dorisae sp. n., P. evae sp. n., and P. quincyae sp. n.. The hemispermatophore of P. dorisae sp. n. is illustrated and described. In addition to the analyses of external morphology and hemispermatophore, we have provided descriptions of the karyotypes of P. dorisae sp. n. and P. quincyae sp. n. Despite the presence of multivalents (CVIII and CXIV), both species exhibit karyotypes with 2n=16 and chromosomes that gradually decrease in length, with the exception of the first chromosome, which is longer than the following chromosomes. A map of distribution of Parabuthus species in the Horn of Africa is included.

Reference:
Kovarik F, Lowe G, Elmi HSA, Stahlavsky F. Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XXX. Parabuthus (Buthidae) (Part III), with description of three new species from Somaliland and occurrence of Parabuthus eritreaensis Kovařík, 2003. Euscorpius. 2024(385):1-27. [Open access]

Family Buthidae

Updated information about the distribution of scorpions in Sudan

 

Manal Siyam and co-workers have recently published a study with updated information about the scorpion fauna of Sudan. Of special interest is the new distributional data about medical important species like Androctonus amoreuxi (Audouin, 1826), Leiurus quinquestriatus (Ehrenberg, 1829) and Parabuthus abyssinicus (Pocock, 1901) (Buthidae). 

Abstract:
Six species of scorpion (Arachnida: Scorpiones) are documented from eighteen localities in seven different states within the Republic of the Sudan. Combining this new data with historical records in the Sudan Natural History Museum and the published literature enables the first provisional distribution maps for Sudanese scorpions. New state records could be added for three medically significant species: Androctonus amoreuxi (Audouin, 1826) from Khartoum, North Kordofan and North Darfur, Leiurus quinquestriatus (Ehrenberg, 1829) from Kassala, River Nile, White Nile and North Darfur, and Parabuthus abyssinicus (Pocock, 1901) from Kassala. Among the less venomous species, we offer new state records for Buthacus leptochelys (Ehrenberg, 1829) in White Nile State, for Compsobuthus werneri (Birula, 1908) in North Kordofan, White Nile and Kassala States and for Orthochirus olivaceus (Karsch, 1881) in River Nile, Northern and Kassala States. Further information about the taxonomy, distribution and toxicity of Sudanese scorpions is presented.

Reference:
Siyam M, Dunlop JA, Kovařík F, Mohammad A. Additions to the distribution of Sudanese scorpions. Zoosystematics and Evolution. 2023;99(1). [Open Access]

Thanks to Matt Simon for informing me about this article!

A review of the scorpions the Arab Countries of the Middle East and their medical importance

 

Zuhair Amr and co-workers have recently published a review on the scorpions of the Arab countries of the Middle East. The article presents a list of scorpions known from the different countries and species of medical importance, treatment and epidemiological data are also given. This is a nice update to the knowledge of the scorpion fauna of this region and its impact on the human population.

Abstract:
The twelve Arab countries of the Middle East are inhabited by 117 species of scorpions of varying medical importance within six families. Scorpion stings are a very common occurrence throughout the region. Twentytwo scorpion species are considered to be dangerously venomous, causing potentially life threatening stings. Accessible literature in English and Arabic on scorpions, scorpion stings and available antivenoms was reviewed to document the scorpion fauna and scorpion stings in each country. Saudi Arabia, Iraq and Jordan report the highest numbers of stings and envenomings. Clinically, the most important toxins in Old World scorpion venoms are α-toxins that target voltage-gated sodium (Nav) channels at neurotoxin binding site 3, causing sympathetic excitation and the endogenous release of catecholamines that is responsible for transient, but life-threatening myocardial damage. Most victims of scorpion stings suffer severe local pain, but a few, especially children, develop systemic envenoming which, in the case of most Middle Eastern buthid species, such as Androctonus and Leiurus species, is dominated by the cardiovascular and respiratory consequences of hypercatecholinaemic myocarditis. Other syndromes include paralysis (Parabuthus leiosoma), coagulopathy (Nebo hierichonticus and Hemiscorpius species), and local tissue damage, haemolysis and acute kidney injury (H. lepturus). Early antivenom treatment is recommended but its value remains controversial. However, intensive care, with the ancillary use of vasoactive drugs such as prazosin and dobutamine, has proved effective.

Reference:
Amr Z, Abu Baker M, Al-Saraireh M, Warrell D. Scorpions and scorpion sting envenoming (scorpionism) in the Arab Countries of the Middle East. Toxicon. 2021;191:83-103. [Subscription required for full text]

Five new Parabuthus species from Somaliland and Ethiopia

Frantisek Kovarik and co-workers recently published part 21 in their ongoing article series on the scorpion fauna in the Horn of Africa. In their latest article, they look further into Parabuthus heterurus Pocock, 1897 (Buthidae) and conclude that this is actually a species complex consisting of four species (three new species). In addition, two more new species are described from Somaliland.

Parabuthus erigavoensis Kovarik, Lowe, Elmi & Stahlavsky, 2019 (new species from Somaliland).

Parabuthus kabateki Kovarik, Lowe, Elmi & Stahlavsky, 2019 (new species from Somaliland).

Parabuthus mazuchi Kovarik, Lowe, Elmi & Stahlavsky, 2019 (new species from Somaliland).

Parabuthus robustus Kovarik, Lowe, Elmi & Stahlavsky, 2019 (new species from Ethiopia and Somaliland).

Parabuthus somalilandus Kovarik, Lowe, Elmi & Stahlavsky, 2019 (new species from Somaliland).

Parabuthus terzanii Rossi, 2017 is synonymized with Parabuthus hamar Kovařík et al., 2016. The former was never listed in The Scorpion Files.

New data on the distribution of Parabuthus of the Horn of Africa are given and an identification key for the genus in the same area is available.

Abstract:
The complex of Parabuthus heterurus Pocock, 1897 is split into four species: P. heterurus Pocock, 1897 s. str. whose type locality and real distribution are discussed and corrected, and three herein described species, P. kabateki sp. n., P. robustus sp. n. and P. somalilandus sp. n. In the species complex of Parabuthus liosoma (Ehrenberg, 1828), P. erigavoensis sp. n. from Somaliland is described. Also described are P. mazuchi sp. n., sympatric with P. cimrmani Kovařík, 2004 and P. eritreaensis Kovařík, 2003 from Somaliland. New data are presented on the distribution of the genus Parabuthus Pocock, 1890 in the Horn of Africa, mainly in Somaliland, acquired during expeditions in 2017–2019. Information is provided about Parabuthus species from Somaliland, their taxonomy, distribution, and ecology, fully complemented with color photos of live and preserved specimens, as well as their habitats. The hemispermatophores of P. kabateki sp. n., P. mazuchi sp. n., P. robustus sp. n. and P. somalilandus sp. n. are illustrated and described. In addition to the analyses of external morphology and hemispermatophores, we also described the karyotypes of P. kabateki sp. n., P. robustus sp. n., and P. somalilandus sp. n. All three species have karyotypes with 2n=16 and chromosomes gradually decreasing in length. Included is a key to Parabuthus Pocock, 1890 in the Horn of Africa. Parabuthus terzanii Rossi, 2017 is synonymized with Parabuthus hamar Kovařík et al., 2016 syn. n. as a junior synonym because the description dated July 2016 was in reality published/accessible in March 2017.

Reference:
Kovarik F, Lowe G, Elmi HSA, Stahlavsky F. Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XXI. Parabuthus (Buthidae) (Part II), with description of five new species from Somaliland and Ethiopia. Euscorpius. 2019(290):1-63. [Open Access]

Family Buthidae

Scorpion envenomations in South Africa during a 10-year period

South Africa harbors a large diversity of scorpions, including many species in the medical important genus Parabuthus Pocock, 1890 (Buthidae). Carine J. Marks and co-workers have recently published a retrospective analysis of the scorpion cases managed by the Tygerberg Poisons Information Centre over a 10 year period.

The main conclusion is that the incidence of severe scorpionism were low in this period. 65% of the sting cases had no or minor symptoms, mainly local pain. As usual, children may be more vulnerable and extra vigilance is needed in cases involving small children. The species involved in the study were usually not involved, but it is well known that Parabuthus granulatus (Ehrenberg, 1831) and P. transvaalicus (Purcell, 1899) are the most dangerous species in South Africa.

Abstract:
Introduction: South Africa has a wide distribution of scorpion species, yet limited data are available regarding the incidence and severity of scorpion envenomation. The aim of this study was to analyse South African epidemiological data of scorpion stings and envenomation as reported to the Tygerberg Poisons Information Centre (TPIC).
Methods: A retrospective analysis was conducted of scorpion-related telephonic consultations to the TPIC over a ten year period (1 January 2005 to 31 December 2014). Data were entered onto a Microsoft Excel® spreadsheet and descriptive statistics are presented for all variables. Associations with severity of envenomation are presented as odds ratios (OR) with 95% confidence intervals (95%CI).
Results: During the study period 52,163 consultations were processed by the TPIC of which 740 (1.4%) cases involved scorpion stings. Of these, 146 (19.7%) cases were deemed serious envenomations. Antivenom was recommended to be administered in 131 (90%) of these cases. Healthcare professionals made most calls (63%), but were less likely to phone for non-serious cases (OR 0.16; 95%CI 0.09 to 0.29). The Western Cape Province had the highest incidence of calls (6.9 scorpion-related calls/100 000 people). Adults (> 20 years) were victims in 71.4% of cases, and were more likely to experience less serious stings (OR 0.57; 95%CI 0.37 to 0.86). The TPIC was consulted within six hours of the sting occurring in 356 (48.1%) cases with a significant association to less severity (OR 3.51; 95%CI 1.9 to 6.3). Only 2% (15) of the scorpions were available for identification.
Conclusion: The incidence of severe scorpionism to the TPIC was low. Care should be taken when children are involved and when calls are received more than six hours after the sting. TPIC consultants as well as healthcare professionals working in semi-arid regions should be aware of these high risk populations.

Reference:
Marks CJ, Muller GJ, Sachno D, Reuter H, Wium CA, Du Plessis CE, et al. The epidemiology and severity of scorpion envenoming in South Africa as managed by the Tygerberg Poisons Information Centre over a 10-year period. African journal of emergency medicine : Revue Africaine de la Medecine d'Urgence. 2019;9(1):21-4. [Open Access]

A review of the scorpions (and other arachnid groups) from Sudan

The Republic of the Sudan is one of the largest countries in East Africa with a large diversity when it comes to habitats and climate. A few new scorpion taxa have been described from Sudan in the last years, but no recent review of the scorpion fauna has been published.

Jason Dunlop and co-workers have recently published a review of the scorpions and other arachnid groups from Sudan. 17 species from the families Buthidae (15) and Scorpionidae (2) were recorded.

Abstract:
Literature-based species lists for arachnids, excluding spiders and mites, found in the Republic of the Sudan are provided. We summarize records, references, and localities for 17 scorpions (Scorpiones), one harvestman (Opiliones), nine pseudoscorpions (Pseudoscorpiones), 21 camel spiders (Solifugae) and one whip spider (Amblypygi). There are no published records of palpigrades (Palpigradi), whip scorpions (Thelyphonida), schizomids (Schizomida) or ricinuleids (Ricinulei), although at least whip scorpions and ricinuleids would not be expected in East Africa based on their current distribution. Key literature for mites and ticks (Acari) is also mentioned. In general, the Sudanese arachnid fauna has not been documented in detail. Many more species, particularly among the harvestmen and pseudoscorpions, are to be expected, and we offer the data gathered here as a baseline for future work.

Reference:
Dunlop JA, Siyam M, Kovarik F. Smaller orders of Arachnida in Sudan: a literature review. Arachnology. 2018;17:449-57.

Thanks to Frantisek Kovarik for sending me their article!

The evolution of dangerous scorpions and their distribution

Wilson Lourenco has recently published an interesting article where he discuss the evolution of scorpion venom and why some species are more dangerous to humans than others. The article also discuss the global distribution of dangerous species. The article mainly focus on the family Buthidae, where we find most dangerous scorpions.

The article is written in a popular science language making it interesting for both experts and laypersons.

Abstract:
This contribution attempts to bring some general information on the evolution and, in particular, on the geographic distribution of scorpion species noxious to humans. Since 95% of the scorpions incidents are generated by specimens of the family Buthidae C. L. Koch, the analysis will be limited to this familial group. As in previous similar contributions, the content of this work is mostly addressed to non-specialists whose research embraces scorpions in several fields such as venom toxins and public health. Only in recent years, efforts have been made to create better links between ‘academic scorpion experts’ and other academic non-specialists who use scorpions in their research. Even if a larger progress can yet be expected from such exchanges, crossed information proved to be useful in most fields of scorpion studies. Since the taxonomy of scorpions is complex, misidentifications and even more serious errors concerning scorpion classification/ identification are often present in the general literature. Consequently, a precise knowledge of the distribution patterns presented by many scorpion groups and, in particular, those of infamous species, proves to be a key point in the interpretation of final results, leading to a better treatment of the problems caused by infamous scorpion species.

Reference:
Lourenco WR. The evolution and distribution of noxious species of scorpions (Arachnida: Scorpiones). J Venom Anim Toxins Incl Trop Dis. 2018;24:1. [Open Access]

Scorpion defensive behaviour and its relation to morphology and performance

Scorpions are infamous for their tail and venomous sting. The sting is used for defense and prey capture, and in some cases during mating. The scorpions tail comes in many shapes and sizes. And different species use their tail different (they sting in different ways).

In a recent study, Pedro Coelho and co-workers have investigated the movement trajectory and kinematics of the defensive strike in seven species of scorpions from two families. Not surprisingly, they discovered that the defensive use of the sting varied between the species. The article try to explain the observed differences by looking at differences in morphology, habitat, behavior and other factors.

PS! Take a look at the excellent video on YouTube explaining the project!

Abstract:
1. Like many other venomous organisms, scorpions use their venom in defence against predators. Scorpions apply their venomous stinger by extending the caudal part of the body, the metasoma, forward towards the attacker. There are considerable differences in metasoma morphology among scorpion species, and these may afford differences in defensive strike performance.
2. We investigated the movement trajectory and kinematics of the defensive strike in seven species of scorpions, and how these variables are related to each other, and to morphology.
3. We recorded defensive strikes using high-speed video, and reconstructed the trajectory of the telson. From these trajectories, we calculated velocity, acceleration and other kinematic variables. To compare strike trajectory shapes, we used geometric morphometrics.
4. We have shown that the defensive strike differs in trajectory shape, speed, path length and duration between scorpion species. Body size is also an important factor affecting strike characteristics. Relative metasoma length and girth may also influence strike performance, as well as strike trajectory shape. Strikes with different trajectories have different kinematic properties: those with open trajectory shapes attain higher speeds.
5. Our results show that performance differences in defensive behaviour between different scorpion species may be partly mediated by morphology, binding together phenotypic, functional and behavioural diversity.

Reference:
Coelho P, Kaliontzopoulou A, Rasko M, van der Meijden A. A ‘striking’ relationship: scorpion defensive behaviour and its relation to morphology and performance. Functional Ecology. 2017; Early View. [Subscription required for full text]

A major review of the Parabuthus of the Horn of Africa

Frantisek Kovarik and co-workers have recently published a major review of the scorpions in the genus Parabuthus Pocock, 1890 (Buthidae) distributed in the countries constituting the Horn of Africa.

The major findings of this study are:

Two new species from Ethiopia.

Parabuthus hamar Kovarik, Lowe, Pliskova & Stahlavsky, 2016
Parabuthus kajibu Kovarik, Lowe, Pliskova & Stahlavsky, 2016

Parabuthus abyssinicus Pocock, 1901 is raised from subspecies status (previously Parabuthus liosoma abyssinicus Pocock, 1901).

The genus Riftobuthus Lourenco, Duhem & Cloudsley-Thompson, 2010 from Kenya is synonymized with Parabuthus Pocock, 1890 and the only species in the genus, Parabuthus inexpectatus Lourenco, Duhem & Cloudsley-Thompson, 2010 is synonymized with Parabuthus pallidus Pocock, 1895.

The Parabuthus liosoma complex is split into three sibling species with separate areas of distribution:  Parabuthus liosoma Ehrenberg, 1828 is now restricted to Yemen and Saudi Arabia. Parabuthus abyssinicus is restricted to Eritrea, Djibouti, central and north-eastern parts of Ethiopia, and Parabuthus maximus Werner, 1913 is distributed to Kenya and Tanzania. The latter decision has greater implications as this means that most Parabuthus liosoma in the pet trade now is actually P. maximus.

This article has great color pictures of both live specimens and morphological details, and also comes with an identification key for the genus in the region.

Abstract:
All Parabuthus species from Eritrea, Ethiopia, and Somaliland were newly collected and are revised for the first time. The complex of Parabuthus liosoma is split into three sibling species with separate areas of distribution: P. abyssinicus Pocock, 1901 (Eritrea, Djibouti, central and north-eastern parts of Ethiopia), P. liosoma (Ehrenberg, 1828) (Yemen and Saudi Arabia), and P. maximus Werner, 1913 (Tanzania and Kenya). P. hamar sp. n. and P. kajibu sp. n., discovered during scorpiological expeditions in 2011–2016, are described. Information is provided about all Parabuthus species from the Horn of Africa, their taxonomy, distribution, and ecology, fully com-plemented with color photos of live and preserved specimens, as well as their habitat. The hemispermatophores of P. abyssinicus and P. kajibu sp. n. are illustrated and described. In addition to the analyses of external morphology and hemispermatophores, we also describe the karyotypes of P. abyssinicus (2n=16), P. kajibu sp. n. (2n=18), and P. pallidus (2n=20). The monotypic genus Riftobuthus Lourenço, Duhem et Cloudsley-Thompson, 2010 is synonymized with Parabuthus, based in part on pectinal tooth count analysis. Phylogenetic scaling and ontogenetic invariance of pectinal tooth count are shown for buthid scorpions. 

Reference:
Kovarik F, Lowe G, Pliskova J, Stahlavsky F. Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part VII. Parabuthus Pocock, 1890 (Buthidae), with Description of P. hamar sp. n. and P. kajibu sp. n. from Ethiopia. Euscorpius. 2016(228):1-58. [Open Access]

Family Buthidae

Scorpion of medical importance and their identification

Scorpions are quite a diverse group with 2301 species around the world (pr 01.08.16). Even though infamous, most scorpions are quite harmless and perhaps around 50 species can cause death or serious morbidity in humans.

The challenge in scorpion sting cases is the correct identification of the scorpion involved. Incomplete identification or misidentification happens, and in some cases this can cause inefficacy in the treatment of the symptoms caused by a dangerous species (or even worsen the outcome).

In a recent article, Wilson Lourenco attempts to explain and elucidate a number of common problems in scorpion identification, taxonomy, distribution and biogeography. The article is written in a language making it possible for non-zoologists to understand and in this way increasing the knowledge about scorpions for both professionals and amateurs. Hopefully, this will also be a tool for those treating scorpion sting patients.

Abstract:
The aim of this contribution is to bring general information on the classification and in particular on the specific identification of scorpion species dangerous to humans. Several generic groups are taken into consideration, but the Neotropical genus Tityus C. L. Koch, 1836 is used as a major example. The content of this paper is mostly addressed to non-specialists whose research embraces scorpions in several fields such as venom toxins and public health. Although efforts have been made in the last 20 years to create better links between ‘true scorpion experts’ and non-specialists who use scorpions in their research, such exchanges had never led to a consensus among those different branches of biological and medical research. Consequently, many cases of species misidentification and even more serious errors concerning scorpion classification/identification are often present in the specialized literature. In conclusion, it is suggested here that the frequent cases of misidentification observed in several reports may induce mistakes in the final interpretation of results, leading only to more inefficacity in the treatment of problems caused by infamous scorpion species.

Reference:
Lourenco WR. Scorpion incidents, misidentification cases and possible implications for the final interpretation of results. J Venom Anim Toxins Incl Trop Dis. 2016;22:1. [Open Access]

Venom spraying in scorpions

It is well known that scorpions use venom in prey capture and defense. This is normally done by injecting venom thought the scorpion's stinger. It is less known that a few species also can spray venom up 50 cm away. This behavior has only been reported from seven species in the South African genus Parabuthus Pocock, 1890 (Buthidae). It has been assumed that the venom spraying behavior has an anti-predator effect against potential predators of scorpions. Getting venom spray into the eyes is probably also harmful for humans, as many Parabuthus scorpions are of medical importance.

Nissani and Hayes have now published a very interesting analysis of the venom spraying behavior in Parabuthus transvaalicus Purcell, 1899, a medical important species from South Africa. Their study supported the hypothesis that that P. transvaalicus modulates venom spraying depending on level of threat. The authors argue that venom spraying increase the likelihood that venom makes contact with sensitive tissues of the predator, particularly its eyes. The authors believe that there is a possibility that scorpions modulate the quantity of venom expelled during spraying, but this requires further investigations.

Abstract:
Many animals use chemical squirting or spraying behavior as a defensive response. Some members of the scorpion genus Parabuthus (family Buthidae) can spray their venom. We examined the stimulus control and characteristics of venom spraying by Parabuthus transvaalicus to better understand the behavioral context for its use. Venom spraying occurred mostly, but not always, when the metasoma (tail) was contacted (usually grasped by forceps), and was absent during stinging-like thrusts of the metasoma apart from contact. Scorpions were significantly more likely to spray when contact was also accompanied by airborne stimuli. Sprays happened almost instantaneously following grasping by forceps (median = 0.23 s) as a brief (0.07 - 0.30 s, mean = 0.18 s), fine stream (< 5 * arc) that was not directed toward the stimulus source; however, rapid independent movements of the metasoma and/or telson (stinger) often created a more diffuse spray, increasing the possibility of venom contact with the sensitive eyes of potential scorpion predators. Successive venom sprays varied considerably in duration and velocity. Collectively, these results suggest that venom spraying might be useful as an antipredator function and can be modulated based on threat.

Reference:
Nisani Z, Hayes WK. Venom-spraying behavior of the scorpion Parabuthus transvaalicus (Arachnida: Buthidae). Behavioural Processes. 2015 Mar 3;115:46-52. [Subscription required for full text]

Metabolic cost of venom regeneration and venom complexity in Parabuthus transvaalicus

It has previously has been showed that venom use is costly, both in terms of metabolic and ecological costs (Nisani et al, 2007; Nisani, 2008), that some scorpions have two types of venom with different composition (and different "production costs") (Inceoglu et al., 2003) and that Parabuthus transvaalicus Purcell, 1899 (Buthidae) are able to regulate venom use at different levels (Click here for more information).

Zia Nisani and co-workers have now further confirmed the relatively high cost of venom regeneration and also have shown that greater venom complexity can be associated with higher cost of venom production.

Abstract:
We investigated the biochemical profile of regenerated venom of the scorpion Parabuthus transvaalicus in relation to its metabolic cost and toxicity. Using a closed-system respirometer, we compared oxygen consumption between milked and unmilked scorpions to determine the metabolic costs associated with the first 192 h of subsequent venom synthesis. Milked scorpions had a substantially (21%) higher mean metabolic rate than unmilked scorpions, with the largest increases in oxygen consumption occurring at approximately 120 h, 162 h, and 186 h post-milking. Lethality tests in crickets indicated that toxicity of the regenerated venom returned to normal levels within 4 d after milking. However, the chemical profile of the regenerated venom, as evaluated by FPLC and MALDITOF mass spectrometry, suggested that regeneration of different venom components was asynchronous. Some peptides regenerated quickly, particularly those associated with the scorpion’s “prevenom,” whereas others required much or all of this time period for regeneration. This asynchrony could explain the different spikes detected in oxygen consumption of milked scorpions as various peptides and other venom components were resynthesized. These observations confirm the relatively high metabolic cost of venom regeneration and suggest that greater venom complexity can be associated with higher costs of venom production.

Reference:
Nisani Z, Boskovic DS, Dunbar SG, Kelln W, Hayes WK. Investigating the chemical profile of regenerated scorpion (Parabuthus transvaalicus) venom in relation to metabolic cost and toxicity. Toxicon. 2012;60(3):315-23. [Subscription required for full text]

Five new anatomy picture collections in The Scorpion Files

Leonard Georg is still using his camera on new species and has made five new, detailed anatomy pictures collections of the following species:

Androctonus amoreuxi
Lychas scutilus
Parabuthus liosoma
Parabuthus villosus (black form)

Belisarius xambeui

A big thanks to Leonard for sharing these great pictures with us!!