Astylus is a section within the genus Nuphar[2][1][3] native to North America.

[5] The androecium consists of laminar stamens[6] with long anthers and short filaments.

[6][7][4] It was described by Donald Jay Padgett in 1999 with Nuphar advena (Aiton) W.T.Aiton as the type species.

Astylus have broad necks, whereas fruits of Nuphar sect.

[4] The fossil species †Nuphar carlquistii from the early eocene of north-central Washington, USA has been identified as member of Nuphar sect.