In order to study how sexual selection takes place during mating, it is necessary to have a clear knowledge of the interactions that occur throughout mating and which morphological and behavioral traits are involved. Available information about harvestman reproductive biology is mainly restricted to anecdotal field observations, most of them lacking a detailed description and quantification of mating behavior. In this paper, we study the reproductive behavior of the gonyleptid Pachyloides thorellii Holmberg, 1878 (Pachylinae) and provide quantitative and descriptive information about its sexual behavior. We observed 15 matings, measured females and males, and analysed our behavioral data in the context of individuals' sizes. We observed conspicuous pre-copulatory, copulatory and post-copulatory courtship. We also found that females have several strategies to reject males' mating attempts. Like most gonyleptids, males and females of P. thorellii mate in face-to-face position; however, we observed that both male and female clasp their chelicerae mutually. This behavior has not previously been reported for the suborder Laniatores. The information obtained through this study establishes the basis for further studies on this species' reproductive biology and supports the suitability of this species as a model to explore the importance of male copulatory courtship for female choice and sperm use.