Image copyright BBC Horizons Image caption Sion Land (left) and Dion Jones make up the rock outfit Alffa

A rock duo have become the first to score one million plays with a Welsh language song on the streaming service Spotify.

Alffa released 'Gwenwyn' - Poison - in July, when it was picked-up and put on influential Spotify playlists.

The band said the milestone was "nuts", with their song being streamed from Brazil to Australia.

They were chosen to be one of BBC Wales' Horizons artists for 2018 - promoting new music from Wales.

"We weren't expecting anything like this," said guitarist and lead singer Dion Jones.

Jones and drummer Sion Land only finished school in the summer, where they were sixth-form students at Ysgol Brynrefail in Llanrug, near Caernarfon.

As part of the Horizons project, which is a collaboration with Arts Council of Wales, they have had the chance to play summer festivals and showcase events, as well as being signed to Welsh label Recordiau Côsh.

The label's founder, Welsh singer-songwriter Yws Gwynedd, said Alffa's success had shown that "language barriers are being blown wide open".

Image copyright Horizons Image caption The Spotify success will help fund the band's first album

Alun Llwyd, who managed one of Wales' most successful musical exports - Super Furry Animals - had a hand in helping ensure Alffa's track got the music industry's attention.

He runs the independent distributor Pyst, which specialises in Welsh artists.

"The most exciting thing to come out of this is how it reflects the output, work ethic and abundance of Welsh labels and artists in Wales," he said.

"This is just the beginning."

Alffa would not say exactly how much income their single had generated for them on Spotify.

However, Jones did tell BBC Wales that it was enough to cover the costs of recording their very first album - which they are in the middle of writing now.

"It's been a good stepping stone, with confidence," he said.

"Hopefully it will push us a little more to do more gigs outside of Wales."