26 May, 2016

The effect of habitat fragmentation on the scorpion assemblage of a Brazilian Atlantic Forest

Human deforestation of the world's tropical rainforests have resulted in habitat destruction and subsequent habitat fragmentation. Lira and co-workers have now published a study that investigated how fragmentation and habitat structure influenced the scorpion assemblage in a hyperfragmented landscape in the northeast Brazilian Atlantic Forest. Not surprisingly, the authors conclude that fragmentation and habitat quality are determining factors for the assemblage of the scorpion populations in this study.

Habitat fragmentation is a topic widely studied in ecology; however, its effects on the assemblage of the order Scorpiones is less well understood. Aiming to fill this gap, this study assessed the effect of fragmentation on the assemblage of these arachnids in 12 Brazilian Atlantic forest fragments. Five environmental variables were measured (depth and dry mass of litter, understory density, canopy openness, and diameter at breast height of the trees), and the fragment area, vegetation cover, connectivity and elevation assessed. The animals were collected during the dry season and, identified at night with the use of ultraviolet light lamps. The analyzed scorpion assemblage in the landscape was characterized by the species Tityus pusillus, T. stigmurus, T. neglectus, T. brazilae, and Ananteris mauryi, with a maximum of three species cooccurring per fragment. Only the fragment size and the dry mass of litter showed a positive relationship with the composition of scorpions. These results suggest that the habitat of scorpions responds to environmental attributes and landscape metrics at both higher (fragment size) and lower (leaf litter) scales. Our study was able to expand our knowledge of how scorpions respond to habitat changes in the Atlantic Forest. We conclude that fragmentation and
habitat quality are determining factors for the assemblage of these arachnids.

Lira AFA, de Araujo VLN, de Souza AM, Rego FNAA, Albuquerque CMR. The effect of habitat fragmentation on the scorpion assemblage of a Brazilian Atlantic Forest. J Insect Conserv. 2016;First online: 14 May 2016. [Subscription required for full text]

Thanks to Andre Lira for sending me their article!

24 May, 2016

Ecology and biogeography of the Romanian scorpion Euscorpius carpathicus

Unlike scorpions from warmer areas, the species in the genus Euscorpius Thorell, 1876 (Euscorpiidae)  have to be dapted to a climate ranging from dry, hot summers to cold, snowy winters. In a recently published article, Iulian Gherghel and co-workers provide an updated overview on the distribution of Euscorpius  carpathicus (Linnaeus, 1767) and a map of of the climatically suitable areas for the species using occurrence and climatic data. In addition, the overwintering behavioral ecology of the species is discussed.

We present a first analysis of the ecology and potential distribution of Euscorpius carpathicus (Linnaeus, 1767), a scorpion species endemic to southern Romania, and report on the overwintering habitat selection of this species. Using field data, literature review, species distribution modelling, and habitat selection models, we document the broad scale distribution and ecology of E. carpathicus, as well as habitat selection in the foothills of the Curvature Carpathians, including exclusive microhabitat selection of riverine clay banks. In contrast with other species of the genus that inhabit cracks in cliffs or walls, E. carpathicus has adapted to cracks in clay.

Gherghel I, Sotek A, Papes M, Strugariu A, Fusu L. Ecology and biogeography of the endemic scorpion Euscorpius carpathicus (Scorpiones: Euscorpiidae): a multiscale analysis. Journal of Arachnology. 2016;44(1):88-91. [Subscription required for full text]

Family Euscorpiidae

A new species of Ananteris from French Guiana

Wilson Lourenco recently published a new article with the description of a new species of Ananteris Thorell, 1891 (Buthidae) from the Mitaraka Massif in French Guiana.

Ananteris polleti Lourenco, 2016

A new remarkable species belonging to the genus Ananteris Thorell, 1891 (Buthidae) is described from the Mitaraka Massif in French Guiana, a site located near the borders of French Guiana, Brazil, and Suriname. The description of this new species brings further evidence about the biogeographic patterns of distribution presented by most species of the genus Ananteris, which are highly endemic in most biogeographic realms of South America, including the Tepuys and Inselberg Massifs.

 Lourenco WR. Scorpions from the Mitaraka Massif in French Guiana. II. Description of a new species of Ananteris Thorell, 1891 (Scorpiones: Buthidae). C R Biol. 2016 May 4. [Open Access]

Family Buthidae

20 May, 2016

What role had the formation of the Andes mountain range on the speciation in the genus Brachistosternus?

The Andes continental mountain chain in South America is one of the worlds longest, and the formation of this mountain chain (The Andean uplift) probably had a major impact of the evolution of plants and animals in this region. The bothriurid genus Brachistosternus Pocock,1893 is endemic to South America and distributed mainly in the Andean region. In a recent article, Sara Ceccarelli and co-workers have investigated the biogeographical history of Brachistosternus to determine the role of Andean uplift on the distribution and diversification of its species.

It is no surprise that this study confirms that the evolution and diversification of Brachistosternus was very much influenced by the major geological changes caused by the Andean uplift.

One of the planet’s most imposing geomorphological features, the Andes, played an important role in the evolution of South America’s flora and fauna. The bothriurid scorpion genus Brachistosternus Pocock, 1893 comprises more than 40 species with high diversity and endemism in the Andes. The present contribution investigates the biogeographical history of this genus using molecular phylogenetics and dating, to determine the role of Andean uplift on the distribution and diversification of its species. 
South America.

A dated species tree was obtained for 55 putative species based on two nuclear and three mitochondrial gene loci. Ancestral ranges and biogeographical events were estimated on the species tree, diversification rates and rate shifts calculated, and areas with high phylogenetic diversity (PD) and evolutionary distinctiveness identified.

Brachistosternus diversified at a steady rate during the main Andean uplift. The central Andean and western slope/Pacific coastal biogeographical provinces played important roles as ancestral areas. Coastal areas of central Chile and southern Peru exhibit high levels of PD in Brachistosternus, suggesting they experienced a relatively long period of ecological stability, while the Andes continued to rise.
Main conclusions 

Andean uplift created new habitats and climate regimes, favouring speciation in genera such as Brachistosternus. Coastal areas to the west of the Andes continued to harbour older lineages while accommodating more recently diverged lineages from the nearby Andes.

Ceccarelli FS, Ojanguren-Affilastro AA, Ramırez MJ, Ochoa JA, Mattoni CI, Prendini L. Andean uplift drives diversification of the bothriurid scorpion genus Brachistosternus. Journal of Biogeography. 2016;Epub 13 May 2016. [Subscription required for full text]

Thanks to Andres Ojanguren-Affilastro for sending me their article!

19 May, 2016

Reproduction and life history in Tityus pusillus

Cleide Albuquerque and Andre Lira have recently published a study on reproductive strategies and life history in the buthid Tityus pusillus Poocock, 1893, the most abundant and widespread scorpion species
in the northeast Brazilian Atlantic Forest.

Two different reproductive strategies were identified in addition to the deferred reproduction previously recorded for this species. The evolution of the reproductive strategies observed is discussed.

A remarkable diversity of life history strategies has evolved among species for achieving reproductive success, including adaptive growth, protandry, iteroparity, and extra molting. Here, we report on the reproductive strategies of the litter-dwelling scorpion, Tityus (Archaeotityus) pusillus, the most abundant and widespread scorpion species in the Atlantic Forest of northeastern Brazil. We observed both iteroparity and protandry reproductive strategies in this species. Females were competent to produce up to three broods after a single insemination, and no correlation between female size and litter size was observed. Most males reached adulthood 1 month before females following four molts, characterizing protandry. Nevertheless, an extra molt was observed to occur in some males (n = 4) and females (n = 1). These findings highlight the life history traits of T. (A.) pusillus, which may imply in reproductive success and adaptation to changes in environmental conditions.

Albuquerque CMRd, Lira AFdA. Insights into reproductive strategies of Tityus (Archaeotityus) pusillus Pocock, 1893 (Scorpiones, Buthidae). Comptes Rendus - Biologies. 2016;In Press.[Subscription required for full text]

Thanks to Andre Lira for sending me his article!

Assasin bug feeding on a Tityus species in Brazil

As previously mentioned in the blog, scorpions have many enemies hunting and feeding on them. Andre Lira and co-workers have now reported about an assasin bug (Heteroptera: Reduviidae) feeding on a Tityus pusillus Pocok, 1893 (Buthidae) in the Brazilian Atlantic Forest. Interestingly, the assasin bug was almost half the size of its scorpion prey. This observation extends the list of invertebrate predators of scorpions.

Litter-dwelling arthropods comprise about three-fourths of the total animal biomass in tropical forests. These invertebrates are involved in many interspecific interactions, from mutualism to predation. We report herein the predation of a scorpion by an immature assassin bug (Harpactorini) during a nocturnal manual search for scorpions in a fragment of the Brazilian Atlantic Forest. The specimens were found 15 cm above the ground on a seedling, and the prey was two-fold larger than the predator. The assassin bug had its rostrum inserted into the pleura of a juvenile Tityus pusillus Pocock, 1893 scorpion, between the first and second segments of the mesosoma; when disturbed, the predator jumped to the leaf litter without releasing its prey. To the best of our knowledge, this is the first report of juvenile predator–prey interactions between a heteropteran and a scorpion in this biome.

Lira AFdA, Araujo VLNd, Albuquerque CMRd. Predation of a scorpion (Scorpiones: Buthidae) by an assassin bug (Heteroptera: Reduviidae) in the Brazilian Atlantic Forest. Turkish Journal of Arachnology. 2016;40:294-6. [Open Access]

Thanks to Andre Lira for sending me his article!

18 May, 2016

A new scorpion book has been published

A new scorpion book has recently been published by Dr. M. Habibulla entitled "The Secretive Life of the Amazing ‘Living Fossil' Scorpion". The book presents different sides of scorpion biology and is illustrated with color pictures. The book may be of interest for both professionals and scorpion enthusiasts.

Publishers overview: 
Scorpions began roaming the earth two hundred million years before dinosaurs, and yet they receive little fanfare. They are usually perceived as threats just waiting to sting and poison anyone they come across—some people even consider them to be evil. But the reality is that these armored arthropods are fascinating, beautiful invertebrates belonging to the group Arachnida, and the living scorpion of today has not changed much from their ancestors that lived hundreds of millions of years ago during the Silurian period. The scorpion has been with us for so long—and has had to evolve so little in terms of its structure and function—that it's now considered a living fossil. It was the first air-breathing, land-dwelling animal to inhabit the planet. They are truly fascinating: Scorpions are highly resistant to radioactivity, they can reproduce without males, they can give birth to as many as sixty little scorpions at a time, and they are so desperate to survive that they'll eat other scorpions when food is scarce. Explore the mysteries of this amazing creature, including its physiology, neurochemistry and natural behavior with The Secretive Life of the Amazing ‘Living Fossil' Scorpion.

Habibulla M. The Secretive Life of the Amazing ‘Living Fossil' Scorpion. Bloomington, IN: Archways Publishing; 2016. 165 pp.

The book is available both in print and as an ebook, and can be purchased from Archways Publishing.

Thanks to Dr. Habibulla for sending me his book!