"Smelling" the enemy triggers anti-predator behavior in Ananteris mauryi

 

Fear is a powerful agent both in humans and animals and has an impact on behavior. For scorpions, the fear of being eaten by a predator (e.g. another scorpion) should promote behavior to avoid this happening. Matheus Feitosa and co--workers have recently publish an study on Ananteris mauryi Lourenço, 1982 (Buthidae) abilities to detect chemical cues left by its predator Tityus pusillus Pocock, 1893 (Buthidae) in the substrate when exploring new sites, and if this results in behavioral responses to avoid the risk of encounters and predation.

Their study confirms that Ananteris mauryi seems to be able to taste/smell its enemy Tityus pusillus because it tended to avoid substrates with chemical traces of T. pusillus. In addition, the taste/smell of its enemy also triggered anti-prdator behaviors like tail wagging.

Abstract:
Fear level and intraguild predation are factors that act together to directly influence animal behavior, population dynamics, and community structure. These factors trigger stress, which promotes behavioral, morphological, physiological, and demographic changes, especially in the prey. Some invertebrates, such as scorpions, are known to have a refined chemoreception system to perceive both prey and predators. Therefore, we investigated the ability of an intraguild prey, the scorpion Ananteris mauryi Lourenço, 1982, to detect chemical traces of its predator, the scorpion Tityus pusillus Pocock, 1893. Our goal was to verify whether A. mauryi exhibits antipredator behavior induced exclusively by chemical cues from its predator. Ananteris mauryi specimens were subjected to two experimental treatments: one with and one without traces of T. pusillus. The results showed that A. mauryi tended to avoid substrates with chemical traces of T. pusillus, confirming its capacity for chemical detection. As a result of this perception, changes in behavioral frequencies were triggered, generating an antipredator behavioral repertoire. These findings were supported by behavioral changes, such as tail wagging, which is performed exclusively by scorpions in the presence of a predator and at imminent risk of predation.

Reference:
Feitosa MLB, Dionisio-da-Silva W, Lira A, Teles-Pontes WJ. Fear as an enemy? Behavioral changes of Ananteris mauryi Lourenço, 1982 (Scorpiones: Buthidae) are triggered by chemical cues from an intraguild predator. Can J Zool. 2022;100:488-93 [Subscription required for full text]

Thanks to Andre Lira for sending me his articles!

The effect of microhabitat use on the foraging and diet of Centruroides vittatus in blackbrush habitat of south Texas

 

Scorpions utilize different habitats and the choice of microhabitat is usually influenced by prey availability, predator size and risk of predation/cannibalism. Neal McReynolds has previously published a couple of articles on habitat selection and prey capture in the buthid Centruroides vittatus (Say, 1821). In his recent study he has investigated the effect of microhabitat use on the foraging and diet of C. vittatus in blackbrush habitat of south Texas.

The main conslusion is that size classes of C. vittatus use vegetation and the ground for various reasons. The uses of these microhabitats are not mutually exclusive. Check out the abstract and the full article for alle the data collected in this interesting study. 

Abstract:
Microhabitat use by predators can be influenced by prey availability, predator size and risk of cannibalism. The preferred microhabitat for a predator can be for foraging, feeding or as a refuge. In this study in south Texas, Centruroides vittatus (Say, 1821) of all size classes utilized both ground and vegetation microhabitats. There was a high proportion of scorpions with caterpillars in legumes and low proportion of scorpions with any of the prey types on the ground. The median height of scorpions with prey did vary, with scorpions on legumes with caterpillar prey the highest and scorpions on other vegetation with dangerous prey the lowest. Intermediate size scorpions used legumes at a high frequency during January–April, and large scorpions used succulents at very high frequency during September–December. Scorpions climbed higher in blackbrush and other legumes than in other vegetation types. These results suggest that scorpions are actively foraging for caterpillars in legumes, and legumes are a quality microhabitat for foraging. The low proportion of scorpions with prey on the ground suggests that C. vittatus feed on prey on vegetation even if the prey was captured on the ground. A possible advantage for the scorpion to handle and consume prey on vegetation is lower predation risk or interference while feeding. The high use of succulents by the large scorpions cannot be explained by foraging success. A possibility is that succulents are preferred refuges by all C. vittatus but smaller scorpions avoid succulents because of the risk of cannibalism by the larger scorpions.

Reference:
McReynolds CN. The effect of microhabitat use on the foraging and diet of the striped bark scorpion, Centruroides vittatus (Buthidae: Scorpiones) in blackbrush habitat of south Texas. J Arachnol. 2022;50(1):90-100. [Open Access]

A new species of Androctonus from Iran

 

Hossein Barahoei and co-workers have recently described a new species in the medical important genus Androctonus Hemprich & Ehrenberg, 1828 (Buthidae) from southeastern Iran.

Androctonus sistanus Barahoei & Mirshamsi, 2022

A redescritpion of Androctonus baluchicus (Pocock, 1900) is also presented and the authors conclude that all previous reports of this species from Iran is probably of Androctonus sistanus and that A. baluchicus is not present in Iran.

Abstract:
The genus Androctonus Hemprich et Ehrenberg, 1828 (Scorpiones: Buthidae) is composed of 33 species and distributed in the Middle East and North Africa. Among these taxa, only Androctonus baluchicus (Pocock, 1900) and A. crassicauda (Olivier, 1807) are reported from Iran. Specimens collected from north of Sistan & Baluchistan Province (southern Iran) from 2016 to 2021 allow to re-assess the taxonomic status of Iranian species. Androctonus baluchicus is re-described and A. sistanus Barahoei et Mirshamsi, sp.n. described from southeast Iran. A. baluchicus is distributed in the Baluchistan region (including
northwest Pakistan, southwest Afghanistan), whereas A. sistanus Barahoei et Mirshamsi, sp.n. is only known the type locality.

Reference:
Barahoei H, Mirshamsi O, Sanchouli N, Moghaddam MG, Lehmann-Graber C, Monod L. Review of Androctonus baluchicus (Pocock, 1900) with description of new species from Iran (Scorpiones: Buthidae). Arthropoda Selecta. 2022;31(2):197-212. [Open Access]

Thanks to Lukasz Kogut for informing me about this article!

Family Buthidae

Yet another new species in the genus Buthus from Spain

 

Rolando Teruel and Carlos Turiel are still publishing new taxa from their ongoing study of the scorpion fauna of the Iberian Peninsula. In the current article a new species of Buthus Leach, 1815 is described from the Cabo de Gata region of southeastern Andalucia in southern Spain.

Buthus iaspis Teruel & Turiel, 2022

Abstract:
The present paper is the fourth contribution of our taxonomic revision of the genus Buthus Leach, 1815 in the Iberian Peninsula. Herein, we describe a new species from the Cabo de Gata region of southeastern Andalucia (southern Spain). This species is morphologically remarkable and resembles only Buthus manchego Teruel & Turin, 2020, known only from the upper Guadina river basin in the Submeseta Sur, in the area where Ciudad Real adjoins Albacete (central Spain). The West European diversity of Buthus now reaches 17 species, all of them being local endemics.

Reference:
Teruel R, Turiel C. The genus Buthus Leach, 1815 (Scorpiones: Buthidae) in the Iberian peninsula. Part 4: A new species from southern Spain. Revista Iberica de Arachnologia. 2022(40):19-29.

Thanks to Rolando and Carlos for sending me their article!

Family Buthidae

Several taxonomic changes after a reanalysis of Microcharmidae, Grosphus and Teruelius

 

 
Graeme Lowe and Frantisek Kovarik recently published an article where they did a morphometric analysis of the family Microcharmidae Lourenco, 1996 and the genera Grosphus Simon, 1880 and Teruelius Lowe & Kovarik, 2019. The following taxonomic decisions were made:

The family Microcharmidae Lourenco, 1996 with its two genera is synomymized with the family Buthidae C. L. Koch, 1837.

The genus Teruelius Lowe & Kovarik, 2019 (22 species) is restored from synonymy with Grosphus Simon, 1880 (14 species).

Two new species are described:

Grosphus angulatus Lowe & Kovarik, 2022 (Madagascar)

Teruelius haeckeli Lowe & Kovarik, 2022 (Madagascar)

Abstract:
The genus Teruelius Lowe & Kovařík, 2019, was created for a subset of species originally included under Grosphus Simon, 1880, but was subsequently synonymized with Grosphus. We reanalyze Teruelius and Grosphus by scoring 45 discrete characters, and 32 discrete + 17 continuous characters, for all 36 included species, plus 11 related buthids as outgroup taxa. Morphometric analyses are systematically applied to quantify variation in continuous characters, including: carapace length, carapace anterior concavity, carapace preocular length, hemispermatophore posterior lobe length, tibial spur length/ tibia distal depth ratio, metasoma I length/ width ratio, pectine tooth length/ width ratio, pedipalp femur petite ‘trichobothrium’ d2 position, pedipalp fixed finger relative position of trichobothria db vs. est, and pedipalp manus relative position of Eb trichobothria. Elliptic Fourier analyses and principal components analyses are applied to quantify variation in sternite IV spiracle aperture profiles, female basal pectinal tooth shapes and telson lateral profiles. Laser light scattering is applied to quantify differences in optical reflectance of sternite VII arising from cuticular lattice microstructures. Spectral image analysis is applied to quantify differences in granulation of metasoma I ventrosubmedian carinae. The use of UV fluorescence as a quantitative taxonomic character is critically reviewed. Six binary characters are proposed for differential diagnosis of Teruelius vs. Grosphus. Phylogenetic analyses rooting trees with 8 individual outgroup taxa, or with multiple outgroup taxa under morphological and molecular backbone constraints, all yield overwhelming support for the monophyly of Teruelius, and the genus is reinstated. The position of outgroup taxon Microcharmus in a separate family is not supported by any diagnostic characters or phylogenetic analysis, and Microcharmidae is synonymized with Buthidae. Two new species, Grosphus angulatus sp. n. and Teruelius haeckeli sp. n. are described.

Reference:
Lowe G, Kovarik F. Reanalysis of Teruelius and Grosphus (Scorpiones: Buthidae) with descriptions of two new species. Euscorpius. 2022(356):1-105. [Open Access]

Family Buthidae

A new study of the genetics of the buthid genus Gint, endemic to the Horn of Africa

 

The genus Gint Kovarik, Lowe, Pliskova & Stahlavsky, 2013 (Buthidae) is endemic to the Horn of Africa with 12 species. Pavel Just and co-workers have recently published a study trying determinate the mechanisms of karyotype differentiation in this genus.

Their results showed that the Gint species exhibited substantial karyotype diversity and a high incidence of chromosome heterozygosity. This stuff is way over my head and I have to refer to the abstract and the article for further details on the study and its implications.

Abstract:
To determine the mechanisms of karyotype differentiation in scorpions of the genus Gint, we employed an integrative approach, combining cytogenetic data and sequence-based phylogeny. We cytogenetically examined six species with emphasis on multivalent meiotic configurations, 18S rDNA and (TTAGG)n distribution and compared chromosomal data with genetic divergence based on analysis of 16S rRNA and COI gene markers. Our results show that Gint species exhibit substantial karyotype diversity (2n = 18–45) and a high incidence of chromosome heterozygosity. Meiotic chromosome chains formed by up to six elements were found in 85% of analysed individuals, causing intraspecific chromosome variation in three species. Fluorescence in situ hybridization revealed that the 18S rDNA distribution pattern differed in Gint species, including at the intrapopulation level, but the chromosomal localization of (TTAGG)n motif was stable across species. Conspicuous interspecific differences in chromosome counts broadly corresponded with genetic divergence among Gint species. Our findings indicate that Gint karyotypes have undergone dynamic reorganization through independent fusions, fissions and reciprocal translocations. Owing to present chromosomal polymorphism, such structural changes shaping the genome architecture appear to be still ongoing in the populations of some Gint species.

Reference:
Just P, Šťáhlavský F, Kovařík F, Štundlová J. Tracking the trends of karyotype differentiation in the phylogenetic context of Gint, a scorpion genus endemic to the Horn of Africa (Scorpiones: Buthidae). Zoological Journal of the Linnean Society. 2022. [Subscription required for full text]

Thanks to Frantisek Kovarik for sending me their article!

Family Buthidae