Gerard Dupre has recently published a checklist of all scorpion taxa reported from Africa. The article also specify endemic taxa for the different countries.
Abstract:
No abstract.
Reference:
Dupre G. Les scorpions d'Afrique. Arachnides. 2024(117):1-72. [Open Access]
Thanks to Gerard for sharing the online archive of Arachnides with The Scorpion Files. Also thanks to ChatGPT/DALL-E for the illustration.
The skin (exoskeleton) of scorpions has many different types of hairs (e.g. trichobothrias and setae). These have many functions, especially as sensory detectors of chemical substances and mechanical vibrations. For taxonomists they are also important morphological characters that can be used to identify taxa.
Trichobothriotaxy is already in great use in diagnosis and description of many taxa (from species level to family level), but the usefulness of the setae (chaetotaxy) is less investigated. Graeme Lowe and Victoria Tang have now published a extensive study of chaetotaxy in scorpions with morphological descriptions of the different setation patterns in different taxa and the possible applications of these in taxonomy.
Interestingly, observations of Olivierus martensii (Karsch, 1879) (Buthidae) seem to indicate that this species uses setae clusters on pedipalps to brush the median ocelli (eyes) during sponge-bathing (cleaning behavior).
Abstract:
Chaetotaxy of the external pedipalp femur and distal ventral pedipalp movable finger was studied in 120 species, 69 genera and 17 families of scorpions. Setation was generally denser in the ‘Buthus’ group, a major arid-adapted buthid lineage distributed across Palearctic deserts. On the external femur, macrosetae formed a prominent cluster, the ‘distal external macrosetal cluster’ (DEMC); on the distal ventral movable finger they formed a dense patch, the ‘distal ventral macrosetal cluster’ (DVMC). In other buthids and non-buthids, the DEMC and DVMC were mostly absent, except in a few arid-adapted genera. Relative setation densities of DEMC and DVMC in different species depended strongly on size, being denser in larger species and sparser in smaller species, while absolute density varied only weakly with size (mean spacing of setae ~200 μm in DEMC, ~40 μm in DVMC). Ontogenetic variation followed similar trends. Multivariate morphometric analyses revealed taxonomic differences in setation patterns. The ‘Buthus’ group, other buthids, and non-buthids, were partially separable according to their spatial profiles of setation. In the ‘Buthus’ group, major genera were separable by spatial and density profiles of setation. In buthids, there were taxonomic differences in external femoral trichobothriotaxy. The ‘Buthus’ and Tityus’ groups were largely separable by proximodistal positioning of trichobothrium e1. Relative setation densities of DEMC and DVMC were positively correlated, in that species with dense DEMCs also tended to have dense DVMCs. In the buthid Olivierus martensii, DEMC and DVMC were observed to brush the median ocelli during sponge-bathing. In all examined buthids, the DEMC was located where it would contact the ipsilateral median ocellus during femoral articulation. Both DEMC and DVMC may assist in the ocular grooming of desert buthids, by removing sand and dust from surfaces of the median ocelli.
Reference:
Lowe G, Tang V. Clustered setation on the pedipalps of buthid scorpions (Scorpiones: Buthidae). Euscorpius. 2024(398):1-77. [Open Access]
Ersen Yagmur recently published an article describing a new species of Alpiscorpius Gantenbein et al., 1999 (Euscorpiidae) from western Turkey.
Alpiscorpius orgeli Yagmur, 2024
Abstract:
A new species Alpiscorpius orgeli sp. nov. is described based on morphological evidence from Demirci District of Manisa Province in western Turkey. With this addition, the number of scorpion species recorded in Turkey now stands at 22 for the Euscorpiidae family and five for the genus Alpiscorpius.
Reference:
Yagmur EA. Alpiscorpius orgeli sp. nov., a new scorpion species from Manisa Province, Turkey (Scorpiones: Euscorpiidae). Zoology in the Middle East. 2024;Published online: 07 Oct 2024. [Subscription required for full text]
Thanks to Ersen and Victoria for sending me this article!
Frantisek Kovarik and co-workers recently published the description of a new species of Uroplectes Peters, 1861 (Buthidae) from Cameroon.
Uroplectes ebogo Kovarik, Stahlavsky & Govorov, 2024
Abstract:
A new species Uroplectes ebogo sp. n. is described from Cameroon, fully illustrated with color photos showing its morphology and habitus. Uroplectes ebogo sp. n. is the only species of the genus with a combination two characters: metasoma without carinae and metasoma V and telson without punctuation. In addition to morphology and hemispermatophore, we also present the information about the karyotype of Uroplectes ebogo sp. n. (2n=24).
Reference:
Kovarik F, Stahlavsky F, Govorov V. Uroplectes ebogo sp. n. (Scorpiones: Buthidae) from Cameroon. Euscorpius. 2024(397):1-13. [Open Access]
Correct identification of scorpions is important and especially in regions and countries where there are several species that can cause serious envenomations. Boujemaa Ajdi and co-workers have recently published an article investigating whether venom molecular mass fingerprint can be used to identify scorpions in Morocco.
I must admit that this paper is a little over my head but the main conclusions seem to be that this method seems to be a reliable tool for the taxonomic identification of scorpions from Morocco. In addition, molecular mass fingerprints of scorpion venoms contain sufficient molecular variations to differentiate scorpion species. The method seems to be promising for rapid molecular identification of scorpions in the future. See paper for more details.
Abstract:
The venom of scorpions has been the subject of numerous studies.
However, their taxonomic identification is not a simple task, leading to
misidentifications. This study aims to provide a practical approach for
identifying scorpions based on the venom molecular mass fingerprint
(MFP). Specimens (251) belonging to fifteen species were collected from
different regions in Morocco. Their MFPs were acquired using MALDI-MS.
These were used as a training dataset to generate predictive models and a
library of mean spectral profiles using software programs based on
machine learning. The computational model achieved an overall recognition capability of 99 % comprising 32 molecular signatures. The
models and the library were tested using a new dataset for external
validation and to evaluate their capability of identification. We
recorded an accuracy classification with an average of 97 % and 98 % for
the computational models and the library, respectively. To our
knowledge, this is the first attempt to demonstrate the potential of
MALDI-MS and MFPs to generate predictive models capable of
discriminating scorpions from family to species levels, and to build a
library of species-specific spectra. These promising results may
represent a proof of concept towards developing a reliable approach for
rapid molecular identification of scorpions in Morocco.
Reference:
Ajdi B, El Hidan MA, El Asbahani A, Bocquet M, Hamza MA, M'Barka E, et al. Taxonomic identification of Morocco scorpions using MALDI-MS fingerprints of venom proteomes and computational modeling. J Proteomics. 2024:105321. [Subscription required for full text]
Albinism is known in many animals, but it is rare in scorpions. Victoria Tang and Zhenbang Liu has now published a very thorough article on this fascinating topic using albinism in Olivierus martensii (Karsch, 1879) (Buthidae) from China as an example.
The authors thoroughly describe and discuss all aspects of albinism in this species (origin of this phenotype, manifestation, and behavioral and ecological consequences of having this phenotype). Scorpion coloration in general is also discussed in relation to albinism.
Abstract:
This is a formal case report for the albinism in Olivierus martensii (Karsch, 1879). Albino phenotype is compared with its normal counterpart in terms of their morphology and behavior by cursory experiments. The examined 7 albino individuals (5 of which were adults) were smaller and more slender than their normal counterparts. However, these quantitative differences were not statistically significant and should be treated with caution due to the low sample size. Their abilities to detect both white light and UV light or UV-excited fluorescence were not significantly undermined, although their tendency to ensure a clear vision through self-cleaning behavior appeared to be reduced. Their heightened visibility on dark, leafmould substrate and greater crypticity on yellowish gravels may play a significant role in their natural survival. Additional evidence is required to substantiate this hypothesis as the function of scorpion coloration has been hardly studied. Several theoretical assumptions were proposed following a literature review on scorpion coloration and fluorescence, and this paper also serves as a brief synopsis of those aspects. Other three rare phenotypes in this species are also reported, defined here as piebaldism, hypomelanism and leucism. Given their existence, it is suggested that the loss of melanin in the epidermis beneath the ocelli is diagnostic for albinism in scorpions.
Reference:
Tang V, Liu Z. Albinism in Olivierus martensii (Karsch, 1879) (Scorpiones: Buthidae). Euscorpius. 2024(396):1-33. [Open Access]
The scorpions' sting and venom use is important in both prey capture and defense. Several studies have previously investigated sting use in defense and also the use of venom (dry versus wet stings and the discovery of prevenom).
Youssef El Joud and co-workers have recently published a study analyzing how various factors such as temperature, prey type, and threatening conditions influence stinging behaviour, venom usage and regeneration in the scorpion Buthus atlantis Pocock, 1889 (Buthidae) from Morocco.
Their study shows that the scorpions are more ready to sting in defense in higher temperatures and that venom expenditure in B. atlantis is regulated by both temperature and threatening conditions.
Abstract:
Understanding animal’s behaviour and adaptation in the face of threats and predators under different biotic and abiotic conditions is fundamental in ecology. In this study we examined defensive behaviour of Buthus atlantis scorpion in order to assess how various factors such as temperature, prey type, and threatening conditions influence stinging behaviour, venom usage and regeneration. Our study had revealed that stings frequency was significantly lower in cooler temperature compared to the medium and warm temperature. Threatening condition had no significant effect in medium and warmer temperature, the difference between the two conditions was only significant in the cooler temperature. Conversely, we had shown that venom expenditure in B. atlantis is regulated by both temperature and threatening conditions. Our results show that scorpions maintained in higher temperatures yielded the greatest amount of venom compared to those in lower temperatures. Analyses of proteins concentration according to temperature and diet variation had revealed that scorpions placed in intermediate (25 ◦C) and warmer temperature (40 ◦C) had a significantly higher venom proteins concentration when compared to the cooler temperature (10 ◦C). Results also showed that scorpions adjust their venom usage based on their perception of danger, which can be influenced by temperature.
Reference:
El Joud Y, El Bouazzaoui A, El-Ghali S, Laghzaoui EM, Toulon O, Ait Larradia M, et al. Assessing the effects of temperature, diet and threat conditions on defensive behaviour and venom regeneration in scorpion (Buthus atlantis). J Therm Biol. 2024;124:103966. [Subscription required for full text]
