Irish writer Rowan Somerville has won the Bad Sex in Fiction Award for his book The Shape of Her.

He triumphed over New Westminster, B.C., writer Annabel Lyon, who had been nominated for her debut novel The Golden Mean.

The dubious honour from London's Literary Review goes to a writer who offends taste with questionable sexual descriptions.

Somerville won in part for the line: "Like a lepidopterist mounting a tough-skinned insect with a too blunt pin he screwed himself into her."

The novel was also cited for the sheer volume of sexual description, involving fumbling encounters between two young people the Guardian described as "wince-inducing."

Past winners of the Bad Sex in Fiction Award include Jonathan Littell and Norman Mailer.

With files from The Canadian Press