Scorpions from Mexico: From Species Diversity to Venom Complexity

Abstract

Scorpions are among the oldest terrestrial arthropods, which are distributed worldwide, except for Antarctica and some Pacific islands. Scorpion envenomation represents a public health problem in several parts of the world. Mexico harbors the highest diversity of scorpions in the world, including some of the world's medically important scorpion species. The systematics and diversity of Mexican scorpion fauna has not been revised in the past decade; and due to recent and exhaustive collection efforts as part of different ongoing major revisionary systematic projects, our understanding of this diversity has changed compared with previous assessments. Given the presence of several medically important scorpion species, the study of their venom in the country is also important. In the present contribution, the diversity of scorpion species in Mexico is revised and updated based on several new systematic contributions; 281 different species are recorded. Commentaries on recent venomic, ecological and behavioral studies of Mexican scorpions are also provided. A list containing the most important peptides identified from 16 different species is included. A graphical representation of the different types of components found in these venoms is also revised. A map with hotspots showing the current knowledge on scorpion distribution and areas explored in Mexico is also provided.

Keywords: buthidae; diplocentridae; diversity hotspots; mexico; nearctic; neotropical; vaejovidae; venom.

Figure 1

Proportion of scorpion diversity in Mexico. (A) Percentage of genera in the families of Mexican scorpions; (B) Percentage of species in the families of Mexican scorpions.

Figure 2

Representative scorpion species of families from Mexico: (A) Adult ♀ Centruroides limpidus (Karsch, 1879) (Buthidae); (B) Adult ♀ Centruroides nigrimanus (Pocock, 1898) (Buthidae); (C) Adult ♂ Hadrurus obscurus Williams, 1970 (Caraboctonidae); (D) Adult ♂ Diplocentrus colwelli Sissom, 1986 (Diplocentridae); (E) Adult ♀ Megacormus segmentatus (Pocock, 1900) (Euscorpiidae); (F) Adult ♂ Franckeus kochi (Sissom, 1991) (Vaejovidae).

Figure 3

Hotspots of scorpion species richness in Mexico, expressed as the number of species per quarter-degree square mapped onto a Mexican geopolitical division map.

Figure 4

Proportion of the different peptides isolated from the venom of Mexican scorpions.