Mating duration and sperm precedence in the spider Linyphia triangularis

The genome sequence of the Common Sheetweb Spider Linyphia triangularis (Clerck, 1757)

We present a genome assembly from a male Linyphia triangularis (Common Sheetweb Spider Arthropoda; Arachnida; Araneae; Linyphiidae). The genome sequence has a total length of 1,349.10 megabases. Most of the assembly (95.36%) is scaffolded into 13 chromosomal pseudomolecules, including the X 1 and X 2 sex chromosomes. The mitochondrial genome has also been assembled and is 15.31 kilobases in length.

Sperm competition when transfer is dangerous

Aggressive and cannibalistic female spiders can impose strong selection on male mating and fertilization strategies. Furthermore, the distinctive reproductive morphology of spiders is predicted to influence the outcome of sperm competition. Polyandry is common in spiders, leading to defensive male strategies that include guarding, plugging and self-sacrifice. Paternity patterns are highly variable and unlikely to be determined solely by mating order, but rather by relative copulation duration, deployment of plugs and cryptic female choice. The ability to strategically allocate sperm is limited, either by the need to refill pedipalps periodically or owing to permanent sperm depletion after mating. Further insights now rely on unravelling several proximate mechanisms such as the process of sperm activation and the role of seminal fluids. This article is part of the theme issue 'Fifty years of sperm competition'.