Sperm viability in spiders: a first approach using Holocnemus pluchei (Scopoli, 1763) (Synspermiata: Pholcidae)

CARGNELUTTI, FRANCO; UÑATES, DIEGO; VRECH, DAVID; BOLATTI, FEDRA; CALBACHO ROSA, LUCIA; CORDOBA-AGUILAR, ALEJANDRO; PERETTI, ALFREDO V.

JOURNAL OF ARACHNOLOGY

AMER ARACHNOLOGICAL SOC

Lugar: Nueva York; Año: 2019

0161-8202

Several studies have shown that sperm viability (SV) is a key trait during sexual competition. However, this hasnot yet been tested in spiders as no protocol has been developed to quantify SV. Here, we describe a methodology forestimating SV using the pholcid spider Holocnemus pluchei (Scopoli, 1763). In this method, male spermatozoa werereleased from the sperm ducts of copulatory bulbs in 50 ll saline solution and mixed with a vortexer. Finally, 10 ll of thesperm solution were combined with 1 ll of GelRed stain. We counted a total of 200 cells and calculated the percentage thatwas not stained. Males showed almost 100% of live sperm inside their genital bulbs. GelRed stain demonstrated a higheffectiveness to distinguish between dead and living sperm cells in spiders and it is thus a more reliable option compared tothe dyes typically used, such as propidium iodide and sybr14. The high SV in H. pluchei may be explained by the multiplemating nature of females, which suggests a selection for enhanced effectiveness during sperm competition within the femalegenital tract.