Microhabitat preferences for the errant scorpion, Centruroides vittatus (Scorpiones, Buthidae)
Abstract
Vegetation as a preferred microhabitat for scorpions has rarely been considered despite many Buthidae (the bark scorpions) being non-burrowing errant scorpions that are active on both the ground and vegetation. Microhabitats can serve multiple functions for Centruroides vittatus (Say 1821), but a particular microhabitat can be preferred for a certain function such as a refuge, foraging, or feeding. Observations of microhabitat use by C. vittatus were performed in Laredo, Texas of the Tamaulipan Biotic Province. Comparisons of microhabitat use by C. vittatus at different temperatures or precipitation levels were performed. Foraging and feeding by C. vittatus among microhabitat classes were also compared. The observed use of vegetation by C. vittatus during different seasons was compared to the expected use based on relative abundance of vegetation in the habitat. Air temperature, but not precipitation, had a significant effect on microhabitat use by C. vittatus. Microhabitat had a significant effect on foraging of C. vittatus with caterpillars comprising 34.6% of the prey items and half of the scorpions feeding on caterpillars were in blackbrush (Acacia rigidula). The lowest proportion of scorpions observed feeding was on the ground (3.8%) and the highest in blackbrush (40.4%). The frequency of C. vittatus among vegetation classes was significantly different compared to the relative abundance of plant species in the plot. Scorpions were observed on prickly pear cactus (Opuntia engelmannii) and strawberry cactus (Echinocereus enneacanthus) at a higher frequency than expected, and scorpions were observed on guajillo (Acacia berlandieri) and tasajillo (Opuntia leptocaulis) at a lower frequency than expected. The frequency of scorpions on blackbrush was higher than expected during the spring. Vegetation is an important microhabitat for C. vittatus in south Texas. The results indicate the possibility that C. vittatus in south Texas used various plant species to carry prey captured on the ground into vegetation to feed, used blackbrush to forage for caterpillars, and used strawberry and prickly pear cacti as a possible refuge.
