19 March, 2022


# Project “Sexual selection and evolution in arachnids”. Grant (three-year) FONCYT PICT 2119/2018.


The project includes both comparative and experimental studies on several species of arachnids (scorpions, solifuges, spiders, pseudo-scorpions), in order to achieve a more integrated knowledge of the study problems. Specifically, it is proposed: 1) to evaluate the existence of chemical intersex communication by means of pheromones, 2) to describe and relate behavioral patterns of courtship and copulation, 3) to study mating systems, 4) to identify the main determinants of successful fertilization, 5) to establish the relationship between reproductive characteristics and the activity of the immune system, 6) to address the study of sperm dynamics in males and females (patterns of viability, production and sperm investment, fertilization patterns), 7) to analyze the relationship between morphological characteristics acting in the precopulatory stage and sperm characteristics resulting in post-copulatory stages, 8) to examine ecological aspects through the study of phenology and characterization of microhabitats, 9) to carry out comparative studies between model species and phylogenetically basal species to establish patterns of evolution of morphological structures and behaviors. The results obtained in this study will not only enrich regional knowledge, but will also serve to test theoretical assumptions about the evolution of mating behavior and sexual selection mechanisms in arthropods in general.

# Project “Reproductive biology of atropods: Patterns and mechanisms of sexual selection in arachnids”. Biannual grant, Consolidar “3” SECYT (UNC) 472/2018.


This project pretends to extend the functional study of mating and associated morphological variables in groups of arachnids and insects in our country, emphasizing in the interpretation of reproductive biology from evolutionary perspectives of sexual and natural selection.

# Project SECyT Estimular 2020-2021 research proyect. “Scorpion biology, consistency in different behavioral traits.”

Director: David E Vrech, Position: Responsible Researcher.

# Project FONCyT B PICT 2019 Proyect PICT-2019-04554. “Scorpion biology: Consistency in different behavioral traits.”

Director: Lucia  Calbacho-Rosa, Position: Responsible Researcher.

# Animal Behavior Society Grant 2022. One procursus to rule them all: possible dual function of a spider genital structure in a sperm competition context


In this project, we will explore the function of the procursus, a sclerite of the copulatory organ in the male pedipalps in the pholcid Gertschiola neuquena. During copulation, the male introduces only one of its copulatory organs in the female genitalia and inserts the long procursus deeply into a long and coiled female spermatheca, whereas the embolus, remains in the anterior section of it. Our preliminary analysis suggests that sperm is present at the posterior end of the spermatheca implying that it is the procursus instead of the embolus, which allocates the sperm deep into the spermatheca. Thereby, the sperm should keep safe from removal by a subsequent male. Additionally, sperm emergence was observed in mated females, indicating a possible sperm removal by rival males. In the context of sperm competition, we hypothesize that the procursus may be used for both proposes. To test it, we will modify the procursus length and analyze the position of the sperm in the spermatheca and the capacity of sperm removal. In other words, whether males can modulate the function of the procursus according to the female status. This is the first study in spiders addressing the functional replacement of the embolus by other parts of the copulatory organ. Thus, our results will contribute to our understanding of the evolution of genitalia and copulatory mechanics in a sperm competition context.

Franco Cargnelutti y Matias Izquierdo: Responsible Researcher.