13 March, 2018

Environmental factors predicting distribution of Androctonus in Morocco

Predicting the occurrence of potential dangerous scorpions in an area may be an important tool in preventing serious sting cases. Moulay Abdelmonaim El Hidan and co-workers have published a study where they have identified environmental factors related to scorpion species occurrence in Morocco (the medical important genus Ancrotonus was chosen), and based on this they have developed scorpion envenomation risk maps for the same areas.

Aim: The objective of this study was to establish environmental factors related to scorpion species occurrence and their current potential geographic distributions in Morocco, to produce a current envenomation risk map and also to assess the human population at risk of envenomation.
Materials and Methods: In this study, 71 georeferenced points for all scorpion species and nine environmental indicators were used to generate species distribution models in Maxent (maximum entropy modeling of species geographic distributions) version 3.3.3k. The models were evaluated by the area under the curve (AUC), using the omission error and the binomial probability. With the data generated by Maxent, distribution and envenomation risk maps were produced using the “ESRI® ArcGIS 10.2.2 for Desktop” software.
Results: The models had high predictive success (AUC >0.95±0.025). Altitude, slope and five bioclimatic attributes were found to play a significant role in determining Androctonus scorpion species distribution. Ecological niche models (ENMs) showed high concordance with the known distribution of the species. Produced risk map identified broad risk areas for Androctonus scorpion envenomation, extending along Marrakech-Tensift-Al Haouz, Souss-Massa-Draa, and some areas of Doukkala-Abda and Oriental regions.
Conclusion: Considering these findings ENMs could be useful to afford important information on distributions of medically important scorpion species as well as producing scorpion envenomation risk maps.

El Hidan MA, Touloun O, Bouazza A, Laaradia MA, Boumezzough A. Androctonus genus species in arid regions: Ecological niche models, geographical distributions, and envenomation risk. Veterinary World. 2018;11(3):286-92. [Open Access]

Thanks to Carlos Turiel for informing me about this article!

08 March, 2018

A review on the scorpionism by the genus Hemiscorpius in Iran

The majority of the literature on scorpionism and medical important scorpions is focused on species on the family Buthidae. But many of the species in the family Hemiscorpiidae can also cause death or serious morbidity. Interestingly, the symptoms of Hemiscorpius Peters, 1861 envenomations are different from the traditional envenomations by buthids. E. g. a sting by the latter will immediately cause pain, while the sting of a Hemiscorpius is usually painless and the patient risk not knowing that a sting has occurred until more serious symptoms occur.

Rouhullah Dehghani and co-workers have now published an interesting review on the scorpionism by Hemiscorpius scorpions in Iran summing up the knowledge on envenomations from these potential dangerous species.

Scorpions are distributed throughout Iran and the genus Hemiscorpius is particularly important in this region. Hemiscorpius lepturus is the most significant species within the genus in the country. Since scorpionism provoked by Hemiscorpius comprises a medical emergency, the present study is focused on this important issue. In order to perform the present work, a review of the medical and health-related literature was carried out in several databases. The current findings indicate that six species of Hemiscorpius are found in 15 states of Iran, mainly in the south and southwest. Deaths caused by stings were reported only for two species. The morphological characteristics and geographical distribution of H. lepturus in Iran, its venom and the toxic compounds, epidemiologic data and clinical manifestations of envenomation as well as treatment for affected people are herein reviewed and described. H. lepturus venom toxicity differs from other Iranian scorpions regarding duration and severity. Scorpionism is an important public health problem in Iran, especially in southwest and south regions and in urban areas. It is more prevalent in children and young people. H. lepturus venom is primarily a cytotoxic agent and has hemolytic, nephrotoxic and to some extent hepatotoxic activity. The use of polyvalent antivenom to prevent scorpion sting symptoms is recommended. A well-planned health education program might be useful in preventing scorpionism.

Dehghani R, Kamiabi F, Mohammadi M. Scorpionism by Hemiscorpius spp. in Iran: a review. J Venom Anim Toxins Incl Trop Dis. 2018;24:8. [Open Access]

Family Hemiscorpiidae

A new species of Leiurus from Algeria

Until 2002, the genus Leiurus Ehrenberg, 1828 (Buthidae) was monotypic with Leiurus quinquestriatus (Ehrenberg, 1828) as the only species. In a recent article, Lourenco and co-workers describe the twelfth species in the genus, this time from Algeria.

Leirurus hoggarensis Loreunco, Kourim & Sadine, 2018

A new species of buthid scorpion belonging to the genus Leiurus Ehrenberg 1828 is described on the basis of four males and six females collected in the region of AmesmessaTamanrasset in the south of Algeria. The new species, Leiurus hoggarensis sp. n., most certainly corresponds to the Leiurus population previously cited by Vachon from both the Hoggar and the Tassili N’Ajjer as Leiurus quinquestriatus. Several characteristics, however, attest that this population is unquestionable distinct from these found in Egypt, and both species can be distinguished by a distinct coloration pattern, different morphometric values and different number of teeth on the pectines. The type locality of the new species represents the most westerly record of the genus Leiurus in Africa, and the new species also inhabit a more mesic zone when compared to the central compartment of the Saharan desert. Leiurus hoggarensis sp. n., apparently does not present characteristics of a psamophilic species and may be considered as a lithophilic species. This is the 12th species to be described for this buthid genus.

Lourenco WR, Kourim ML, Sadine SE. Scorpions from the region of Tamanrasset, Algeria. Part II. A new African species of the genus Leiurus Ehrenberg, 1828 (Scorpiones: Buthidae). Arachnida - Rivista Aracnologica Italiana. 2018;4(16):3-14.

Thanks to Dr. Salah Eddine Sadine for informing me about their article!

Family Buthidae