Phoretic relationship between rodents and pseudoscorpions (Arachnida) in Chiapas, México

Abstract

Phoresy is defined as a non-parasitic association between an animal of small body size (phoront) and a large one (dispersal host), where the larger individual transports the smaller one.  Rodents are frequently reported as dispersal hosts, of which 39 species are phoretic on 21 species of pseudoscorpion.  The present note reports the incidental finding of the relationship between rodents and pseudoscorpions in 2 localities in Chiapas, México.  Rodents were collected using Sherman live traps in an evergreen tropical forest at Ocuilapa de Juárez, municipality of Ocozocoautla, Chiapas, México.  Pseudoscorpions were removed from the rodents using fine-tipped tweezers, stored in vials with 70 % alcohol, and processed for taxonomic identification.  Five Epichernes navarroi pseudoscorpions were found associated with 2 species of rodents: Peromyscus mexicanus and Heteromys desmarestianus.  Three pseudoscorpions were found with their chelae clamped to the hair near the base of the tail of P. mexicanus and 2 attached to the hair of the left hind leg of H. desmarestianus.  All recorded arachnids were females; 3 had a newly formed brood sac containing 23 to 25 eggs each.  There is an active phoretic relationship between Epichernes and the genera Heteromys and Peromyscus, probably due to their overlapping distribution ranges.  This association is likely established in the nest of rodents.  This work is the first to record the phoretic relationship between P. mexicanus, H. desmarestianus, and E. navarroi; besides, it is the first time that this pseudoscorpion species is reported for Chiapas, thus broadening its known distribution range in southeastern México.