Wilson R. Lourenço

Biogeographic patterns of tropical south American scorpions

Based on the personal biogeographic research of the author a review of the major patterns of distribution and differentiation of tropical South American scorpions is proposed in this paper. The principal corridors of distribution are defined and examples are given to illustrate the cases of monomorphic, polytypic, mosaic polymorphic, clinal polymorphic and ochlospecies polymorphic species for both savanna and rainforest. Some examples of disrupted distributions of genera and species in forest and savanna formation are added.

Stridulatory apparatus and the evolutionary significance of sound production in Rhopalurus species (Scorpiones: Buthidae)

The presence of stridulatory apparatus is demonstrated in all known species of the scorpion genus Rhopalurus . Scanning electron microscope photographs are reproduced and, for the first time, are accompanied by sonograms (spectrograms). The probable aposematic role of sound production in scorpions is discussed.

Les peuplements des scorpions des Antilles; facteurs historiques et écologiques en association avec les stratégies biodémographiques

Compilation and analysis of geographic distribution of Antillean scorpion genera and species reveal two major overall distribution patterns in Antillean scorpions. The first one, found among most of the Ischnuridae and Diplocentridae scorpions, but also among some of the Buthidae scorpions, seems to be related with the earliest scorpion colonizers of the Antilles. This pattern supports a limited vicariance model for these early colonizers and a more plausible dispersal model taking into account Tertiary geography and Pleistocene climatic cycles; therefore, the major explanation for this first overall pattern is based on historical factors, and concerns equilibrium or K‐selected species. The second pattern takes largely in account recent ecological factors (e.g. natural cataclysms and anthropic action) that operate particularly in the Lesser Antilles; it concerns opportunistic or r‐selected species, mostly belonging to the Buthidae family.

Interspecific hybridation of laboratory reared Centruroides gracilis and Centruroides margaritatus (Chelicerata, Scorpiones)

Three cases of hybridization obtained in laboratory conditions between Centruroides gracilis and Centruroides margaritatus bring some evidence on the genetic relationship between these two species. The experiments were done with specimens collected in Florida (USA), Mexico and Colombia.