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bioRxiv · 10.1101/479485

Immunological female role tested on artificial plugs in three scorpion species

Oviedo-Diego, M.·Mattoni, C.·Peretti, A. V.
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Abstract

Within arachnids, genital plugs are morphologically diverse, and they can be formed by male, female or be a contribution of both sexes. Although several species of scorpions with genital plugs are known, the physiological effects on the female after being plugged have not been well studied yet. This work compares three scorpion species, two with genital plugs and one without. We first describe the genital plugs morphology of two Urophonius species. Second, through the placement of artificial genital plugs in the female genital atrium, we tested 1) whether there are interspecific differences in the immune encapsulation response on the artificial genital plug, 2) if there are an effect in the hemocyte load in the hemolymph, and 3) if individuals immunological parameters and body weight are correlated. Additionally, we describe and quantify the hemocytes in these species. In both species of Urophonius, genital plugs were found covering the female genital aperture and blocking the genital atrium. The plugs consist of three zones that are distinct in morphology and coloration. We found different patterns of encapsulation and melanization on the artificial plug according to the species, with a greater and more specific response in females of plug producing species. Also, these species showed a decrease in the hemocyte load one month after the placement of the artificial plug, possibly due to the recirculation of the hemocytes into the genital area. In addition, correlations were found between the body weight and the immunological parameters, as well as between different immunological parameters. Our results suggest that females contribute to the formation of genital plugs by adding material and generating the darkening of the genital plugs in certain zones. This comparative study can help to provide a wider framework of different physiological consequences related to a particular postcopulatory mechanism such as the genital plugs.

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Oviedo-Diego, M., Mattoni, C., Peretti, A. V.. 2018-11-26. Immunological female role tested on artificial plugs in three scorpion species. https://doi.org/10.1101/479485

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