Geographical analysis of scorpion populations on habitat islands

Abstract

We examined the population structure of sand scorpions (Paruroctonus mesaensis) by performing genetic and morphological analyses. Sand scorpions were expected to show large genetic distances among populations because they are limited to sandy habitats. However, allozyme analysis showed only moderate genetic differentiation among populations. The morphological analysis showed a geographical association among regional sites. A positive association was found among genetic, morphological and geographical distance matrices. However, the morphological distance matrix showed a higher correlation value with geographical distance than with genetic distance. This result suggests that local environmental conditions may affect scorpion morphology more than they affect genetic structure among populations. The sand scorpion population structure can be described as one with gene flow among populations in the middle of the range and increased isolation along the range boundaries. The major mechanism of genetic exchange is probably sand corridors that periodically connect different sand dune systems. As the age of the North American Sonoran Desert may be less than 10000 years, it is also possible that isolation has not existed long enough to differentiate the populations to a greater extent.

Population and colony structure of the carpenter ant Camponotus floridanus

“…We therefore used our results (band-sharing coefficients) to detect possible population substructuring in C. jloridunus. F , of the three populations of C.floTidnnus (0.19 f 0.09) is similar to that in comparable studies on other arthropods with population substructuring due to limited migration and/or small population size (sand scorpion Parurocfonus mesaensis, Fsr = 0.18, Yamashita & Polis 1995; two wing-reduced carabid beetles: Fsr -0.27 and 0.26, Liebherr 1986; different island populations of the ant Formica truncorum: Fsr = 0.19, Sundstrom 1993).…”

Caporiacco, 1950, stat. nov. (Scorpiones: Euscorpiidae): molecular (allozymes and mtDNA) and morphological evidence for an endemic Balearic Islands species

“…Because scorpions are sit-and-wait predators and generally known to have a low dispersal rate (Polis et al 1985) it is not surprising that members of the genus Euscorpius are highly structured genetically as indicated by high FsT estimates even among mainland populations (Table 2, Appendices 1-2). This finding parallels the genetic population structures of other scorpions such as Paruroctonus mesaensis Stahnke, 1957 (Vaejovidae;Yamashita & Polis 1995;Yamashita & Fet 2001) and in Mesobuthus Vachon, 1950 (Buthidae;Gantenbein et al 2000b), that showed restricted gene flow among metapopulations. These estimates of genetic differentiation are even higher than those measured in salamanders and gophers with Fs,'s of 0.53 and 0.23, respectively (Hewitt & Butlin 1997).…”

The genetic population structure of Buthus occitanus (Scorpiones: Buthidae) across the Strait of Gibraltar: calibrating a molecular clock using nuclear allozyme variation

“…The nuclear genetic data show that population differentiation among north African population samples is considerable (mean F ST over Moroccan populations is 0.79). This suggests a strong genetic structure among the Moroccan subspecies into small ‘habitat islands’ (Gantenbein, Soleglad & Fet, 2001; Yamashita & Polis, 1995).…”