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Eran Gefen - One of the best experts on this subject based on the ideXlab platform.

  • the relative importance of respiratory water loss in scorpions is correlated with species habitat type and activity pattern
    Physiological and Biochemical Zoology, 2011
    Co-Authors: Eran Gefen
    Abstract:

    AbstractScorpions exhibit some of the lowest recorded water loss rates compared with those of other terrestrial arthropods of similar body size. Evaporative water loss (EWL) includes cuticular transpiration and respiratory water loss (RWL) from gas exchange surfaces, that is, book lung lamellae. Estimated fractions of cuticular and respiratory losses currently available from the literature show considerable variation, at least partly as a result of differences in methodology. This study reports RWL rates and their relative importance in scorpions from two families (Buthidae and Scorpionidae), including both xeric and mesic species (or subspecies). Two of the included Buthidae were surface-dwelling species, and another inhabits empty burrows of other terrestrial arthropods. This experimental design enabled correlating RWL importance with scorpion phylogeny, habitat type, and/or homing behavior. Buthidae species exhibited significantly lower EWL rates compared with those of Scorpionidae, whereas effects of ...

  • The effect of desiccation on water management and compartmentalisation in scorpions: the hepatopancreas as a water reservoir.
    The Journal of experimental biology, 2005
    Co-Authors: Eran Gefen
    Abstract:

    Scorpions of the Family Buthidae have lower water loss rates (WLR) and enhanced osmoregulatory capacities in comparison with sympatric species of F. Scorpionidae. In this study we followed changes in water content of different body compartments in four scorpion species under prolonged desiccation conditions. The high initial WLR previously reported for Scorpionidae result in rapid depletion of body water stores. A significant decrease in total body water content of Scorpionidae was recorded following loss of only 5% of initial mass, whereas no such decrease was recorded for Buthidae following severe desiccation. When desiccated, scorpions lose water primarily from the hepatopancreas, while haemolymph volume is more tightly regulated. However, the haemolymph volume of Scorpionidae decreases as a result of depletion of hepatopancreas water stores following severe desiccation. The increasing lipid fraction in the hepatopancreas of Scorpionidae during desiccation suggests that depletion of body water stores may induce enhanced catabolism of carbohydrates, which may contribute to volume regulation by making initially glycogen-bound water available to the desiccating scorpion.

  • Comparative water relations of four species of scorpions in Israel: evidence for phylogenetic differences
    The Journal of Experimental Biology, 2004
    Co-Authors: Eran Gefen, Amos Ar
    Abstract:

    In an attempt to determine the nature of possible interspecific differences in osmotic responses to dehydration, the following species of two scorpion families were examined: Scorpio maurus fuscus (Scorpionidae) and Buthotus judaicus (Buthidae) from the mesic Lower Galilee (mean annual precipitation ∼525 mm); and Scorpio maurus palmatus (Scorpionidae) and Leiurus quinquestriatus (Buthidae) from the xeric Negev Desert (mean annual precipitation ∼100 mm). When sampled in the laboratory following their capture , B. judaicus (548±38 mOsm l–1; mean ± s.d.) and L. quinquestriatus (571±39 mOsm l–1) had higher and less variable haemolymph osmolarities than the scorpionids occupying the same habitats (511±56 and 493±53 mOsm l–1 for S. m. fuscus and S. m. palmatus , respectively). In response to 10% mass loss when desiccated at 30°C, the haemolymph osmolarity of the two buthids increased by 5–9%, compared to ca. 23% in the two scorpionids. Buthids had lower water loss rates than scorpionids. The similar oxygen consumption rates, when converted to metabolic water production, imply a higher relative contribution of metabolic water to the overall water budget of buthids. This could explain why the osmoregulative capabilities exhibited by buthids are better than those of scorpionids. We conclude that the observed interspecific differences in water and solute budgets are primarily phylogenetically derived, rather than an adaptation of the scorpions to environmental conditions in their natural habitat.

  • Comparative water relations of four species of scorpions in Israel: evidence for phylogenetic differences.
    The Journal of experimental biology, 2004
    Co-Authors: Eran Gefen, Amos Ar
    Abstract:

    In an attempt to determine the nature of possible interspecific differences in osmotic responses to dehydration, the following species of two scorpion families were examined: Scorpio maurus fuscus (Scorpionidae) and Buthotus judaicus (Buthidae) from the mesic Lower Galilee (mean annual precipitation approximately 525 mm); and Scorpio maurus palmatus (Scorpionidae) and Leiurus quinquestriatus (Buthidae) from the xeric Negev Desert (mean annual precipitation approximately 100 mm). When sampled in the laboratory following their capture, B. judaicus (548+/-38 mOsm l(-1); mean +/- S.D.) and L. quinquestriatus (571+/-39 mOsm l(-1)) had higher and less variable haemolymph osmolarities than the scorpionids occupying the same habitats (511+/-56 and 493+/-53 mOsm l(-1) for S. m. fuscus and S. m. palmatus, respectively). In response to 10% mass loss when desiccated at 30 degrees C, the haemolymph osmolarity of the two buthids increased by 5-9%, compared to ca. 23% in the two scorpionids. Buthids had lower water loss rates than scorpionids. The similar oxygen consumption rates, when converted to metabolic water production, imply a higher relative contribution of metabolic water to the overall water budget of buthids. This could explain why the osmoregulative capabilities exhibited by buthids are better than those of scorpionids. We conclude that the observed interspecific differences in water and solute budgets are primarily phylogenetically derived, rather than an adaptation of the scorpions to environmental conditions in their natural habitat.

Zhu Ming-sheng - One of the best experts on this subject based on the ideXlab platform.

Amos Ar - One of the best experts on this subject based on the ideXlab platform.

  • Comparative water relations of four species of scorpions in Israel: evidence for phylogenetic differences
    The Journal of Experimental Biology, 2004
    Co-Authors: Eran Gefen, Amos Ar
    Abstract:

    In an attempt to determine the nature of possible interspecific differences in osmotic responses to dehydration, the following species of two scorpion families were examined: Scorpio maurus fuscus (Scorpionidae) and Buthotus judaicus (Buthidae) from the mesic Lower Galilee (mean annual precipitation ∼525 mm); and Scorpio maurus palmatus (Scorpionidae) and Leiurus quinquestriatus (Buthidae) from the xeric Negev Desert (mean annual precipitation ∼100 mm). When sampled in the laboratory following their capture , B. judaicus (548±38 mOsm l–1; mean ± s.d.) and L. quinquestriatus (571±39 mOsm l–1) had higher and less variable haemolymph osmolarities than the scorpionids occupying the same habitats (511±56 and 493±53 mOsm l–1 for S. m. fuscus and S. m. palmatus , respectively). In response to 10% mass loss when desiccated at 30°C, the haemolymph osmolarity of the two buthids increased by 5–9%, compared to ca. 23% in the two scorpionids. Buthids had lower water loss rates than scorpionids. The similar oxygen consumption rates, when converted to metabolic water production, imply a higher relative contribution of metabolic water to the overall water budget of buthids. This could explain why the osmoregulative capabilities exhibited by buthids are better than those of scorpionids. We conclude that the observed interspecific differences in water and solute budgets are primarily phylogenetically derived, rather than an adaptation of the scorpions to environmental conditions in their natural habitat.

  • Comparative water relations of four species of scorpions in Israel: evidence for phylogenetic differences.
    The Journal of experimental biology, 2004
    Co-Authors: Eran Gefen, Amos Ar
    Abstract:

    In an attempt to determine the nature of possible interspecific differences in osmotic responses to dehydration, the following species of two scorpion families were examined: Scorpio maurus fuscus (Scorpionidae) and Buthotus judaicus (Buthidae) from the mesic Lower Galilee (mean annual precipitation approximately 525 mm); and Scorpio maurus palmatus (Scorpionidae) and Leiurus quinquestriatus (Buthidae) from the xeric Negev Desert (mean annual precipitation approximately 100 mm). When sampled in the laboratory following their capture, B. judaicus (548+/-38 mOsm l(-1); mean +/- S.D.) and L. quinquestriatus (571+/-39 mOsm l(-1)) had higher and less variable haemolymph osmolarities than the scorpionids occupying the same habitats (511+/-56 and 493+/-53 mOsm l(-1) for S. m. fuscus and S. m. palmatus, respectively). In response to 10% mass loss when desiccated at 30 degrees C, the haemolymph osmolarity of the two buthids increased by 5-9%, compared to ca. 23% in the two scorpionids. Buthids had lower water loss rates than scorpionids. The similar oxygen consumption rates, when converted to metabolic water production, imply a higher relative contribution of metabolic water to the overall water budget of buthids. This could explain why the osmoregulative capabilities exhibited by buthids are better than those of scorpionids. We conclude that the observed interspecific differences in water and solute budgets are primarily phylogenetically derived, rather than an adaptation of the scorpions to environmental conditions in their natural habitat.

Lorenzo Prendini - One of the best experts on this subject based on the ideXlab platform.

  • Out of India, thrice: diversification of Asian forest scorpions reveals three colonizations of Southeast Asia
    Scientific Reports, 2020
    Co-Authors: Stephanie F. Loria, Lorenzo Prendini
    Abstract:

    The ‘Out of India’ hypothesis is often invoked to explain patterns of distribution among Southeast Asian taxa. According to this hypothesis, Southeast Asian taxa originated in Gondwana, diverged from their Gondwanan relatives when the Indian subcontinent rifted from Gondwana in the Late Jurassic, and colonized Southeast Asia when it collided with Eurasia in the early Cenozoic. A growing body of evidence suggests these events were far more complex than previously understood, however. The first quantitative reconstruction of the biogeography of Asian forest scorpions (Scorpionidae Latreille, 1802: Heterometrinae Simon, 1879) is presented here. Divergence time estimation, ancestral range estimation, and diversification analyses are used to determine the origins, dispersal and diversification patterns of these scorpions, providing a timeline for their biogeographical history that can be summarized into four major events. (1) Heterometrinae diverged from other Scorpionidae on the African continent after the Indian subcontinent became separated in the Cretaceous. (2) Environmental stresses during the Cretaceous–Tertiary (KT) mass extinction caused range contraction, restricting one clade of Heterometrinae to refugia in southern India (the Western Ghats) and Sri Lanka (the Central Highlands). (3) Heterometrinae dispersed to Southeast Asia three times during India’s collision with Eurasia, the first dispersal event occurring as the Indian subcontinent brushed up against the western side of Sumatra, and the other two events occurring as India moved closer to Eurasia. (4) Indian Heterometrinae, confined to southern India and Sri Lanka during the KT mass extinction, recolonized the Deccan Plateau and northern India, diversifying into new, more arid habitats after environmental conditions stabilized. These hypotheses, which are congruent with the geological literature and biogeographical analyses of other taxa from South and Southeast Asia, contribute to an improved understanding of the dispersal and diversification patterns of taxa in this biodiverse and geologically complex region.

  • © Insect Systematics & Evolution (Group 9) Revision of the genus Lisposoma Lawrence, 1928 (Scorpiones: Bothriuridae)
    2015
    Co-Authors: Lorenzo Prendini
    Abstract:

    represents one of two basal African genera in the Gondwanan family Bothriuridae Simon, 1880. All other, more derived genera of Bothriuridae occur in South America, India and Australia. Although the phylogenetic position of Lisposoma has become an increasingly con-tentious subject, three cladistic analyses based on morphological data have confirmed that it is a basal bothriurid. In view of those findings, the present contribution serves to revise the generic diagnosis of Lisposoma, last revised by Lamoral (1979), who placed the genus in the Scorpionidae Latreille, 1802 and constructed his diagnosis accordingly. A considerable num-ber of new specimens, many representing new records for the two species of Lisposoma, have also accumulated since Lamoral’s (1979) revision. These new data justify the provision of revised diagnoses and descriptions for the two species, together with a key to their identifica-tion, brief summaries of their ecology and conservation status, and a distribution map plotting all known locality records

  • systematics and biogeography of the family Scorpionidae chelicerata scorpiones with a discussion on phylogenetic methods
    Invertebrate Systematics, 2003
    Co-Authors: Lorenzo Prendini, Timothy M Crowe, Ward C Wheeler
    Abstract:

    A cladistic analysis of relationships among the genera of Scorpionidae Latreille, 1802—Heterometrus Ehrenberg, 1828; Opistophthalmus C. L. Koch, 1837; Pandinus Thorell, 1876; and Scorpio Linnaeus, 1758—based on morphology and DNA sequence data from loci of three genes in the mitochondrial genome (12S ribosomal DNA (rDNA), 16S rDNA and cytochrome oxidase I) and one gene in the nuclear genome (28S rDNA) is presented. The analysis makes use of exemplar species, specifically selected to test the monophyly of the genera, rather than supraspecific terminal taxa. Other methods used in the analysis are justified in the context of a discussion of current methods for phylogenetic reconstruction. Relationships among the scorpionid genera are demonstrated to be as follows: (Opistophthalmus (Scorpio (Heterometrus + Pandinus))). This reconstruction identifies Opistophthalmus as the basal lineage of the Scorpionidae, rather than the sister-group of Scorpio. Revised descriptions, diagnoses and a key to identification of the four scorpionid genera are provided, together with a summary of what is known about their ecology, distribution and conservation status.

  • Revision of the genus Lisposoma Lawrence, 1928 (Scorpiones: Bothriuridae)
    Insect Systematics & Evolution, 2003
    Co-Authors: Lorenzo Prendini
    Abstract:

    The endemic Namibian genus Lisposoma Lawrence, 1928, comprising two described species, represents one of two basal African genera in the Gondwanan family Bothriuridae Simon, 1880. All other, more derived genera of Bothriuridae occur in South America, India and Australia. Although the phylogenetic position of Lisposoma has become an increasingly contentious subject, three cladistic analyses based on morphological data have confirmed that it is a basal bothriurid. In view of those findings, the present contribution serves to revise the generic diagnosis of Lisposoma, last revised by Lamoral (1979), who placed the genus in the Scorpionidae Latreille, 1802 and constructed his diagnosis accordingly. A considerable number of new specimens, many representing new records for the two species of Lisposoma, have also accumulated since Lamoral's (1979) revision. These new data justify the provision of revised diagnoses and descriptions for the two species, together with a key to their identification, brief summaries of their ecology and conservation status, and a distribution map plotting all known locality records.

Jiao Guo-bin - One of the best experts on this subject based on the ideXlab platform.