Founder and lead vocalist of the Slits, and technically stepdaughter of the five years older John Lydon,Arianne "Ari-Up" Foster died on Thursday of cancer, aged only 48.

Ariane's mother, a German heiress and model, was the partner of ex-Sharks guitarist Chris Spedding when he produced the sex Pistols first demo; Nora Foster was a key figure behind the scenes in the early punk days. Ari and three other non-musicians formed The Slits, an all-girl group, in 1976-77. Their calling card was their feisty, confrontational attitude, very unusual for the time. Not conventionally "glamorous", Ari was nonetheless possessed of a primal sexuality that made her an ideal frontwoman in an era when barriers were being broken down.

I saw the Slits live in early '79. Let's be honest, on stage they had attitude by the bucketload, but as musicians they were Godawful. Starting and finishing songs in the same key and tempo was a matter of pure chance, while Ari alternated between haranguing the audience in a Jamaican accent and coming out with jokes like "What's green and smells? Kermit's bum". Seeing them was seldom a forgettable experience. In 1979 they released "Cut", produced by reggae veteran Dennis "Blackbeard" Bovell of Matumbi, appearing naked apart from grass skirts and covered with mud on the cover. The first single of it was "Typical Girls" -

The B-side was produced by the Slits and Rema, and the single says "Marvin Creates It The Slits Rate It" - a snippet from it became the theme to a BBC TV programme in the eighties. I'm pretty sure the drummer here was a session player, as the drum part is very similar to Errol Dunkley's London made recut of "A Little Way Different", released around the same time.

Unlike many of the punks who regarded Jamaica and Rastafari as an accessory, Ari-Up walked the walk, moving in the eighties to Maxfield Avenue, Kingston, close by Channel One Studios, where as I posted last week the Overnight Players had to work through the night as the streets were unsafe after dark. The studios closed down after one of the Hoo Kim Brothers was killed nearby. In 1994, while Ari was pregnant with her third child, her partner was likewise shot dead.

Returning to Britain and the USA, reforming the Slits and releasing a new album (with Sex Pistol Paul Cook's daughter Hollie in the group; thus one of the Sex Pistols married her mother, while another one's child was her bandmate), she played her last tour in 2010. Reports of performances were mixed, but it is now clear that she was already seriously ill. Having seen Bob Marley live in Glasgow two months before his famous collapse in New York, and knowing how unwell he seemed compared to seeing him previously, it is little surprise that Ari was not focussed on her vocals.

She was, in conclusion, a truly unique performer.