Disclosing aspects of sperm production in Timogenes scorpions (Arachnida, Scorpiones, Bothriuridae)

VRECH D. E., MATTONI C. I. & PERETTI A. V.

Pirenópolis

Congreso; 46th Annual Meeting of the Animal Behavior Society; 2009

Animal Behavior Society

Sperm production studies are gradually arising in arachnids. Unfortunately, little is known in scorpions. These arachnids perform a rather complex courtship with indirect sperm transfer using a spermatophore. Generally, spermatozoa are grouped in sperm packages inside the spermatophore. This work aims to study variables of sperm production and courtship duration, and their possible associations. Timogenes dorbignyi and T. elegans were used as model organisms. Examined variables were male body size and weight, mating duration, spermatophore length, ejaculate volume, number of sperm packages and testis size. Courtship sequences with females were recorded on digital video. Spermatophores were removed before sperm transfer to analyze sperm production. Males from T. dorbignyi are smaller and lighter than T. elegans’. Preliminary results showed that sperm drop volume averages 0.67µl for the former and 2.64µl in the latter. Mating duration varied a lot in both species. Male weight and sperm drop volume showed no tendency to be related between males of the same species, and seemed to be independent to other variables like mating duration. These and other results are discussed under sexual selection hypotheses. This work is the first of its type in scorpions with techniques and measures never used before on them.