Silmud (Lampetra), silmlaste (Petromyzontidae) sugukonda kuuluvate lõuatute perekond.
Perekonda kuulub 12 liiki (FishBase, veebruar 2018):
Lampetra aepyptera (C. C. Abbott, 1860) (least brook lamprey) - niresilm
Lampetra alavariensis Mateus, Alves, Quintella & P. R. Almeida, 2013 – aveiro silm
Lampetra auremensis Mateus, Alves, Quintella & P. R. Almeida, 2013 – ouremi silm
Lampetra ayresii (Günther, 1870) – lääneameerika silm
Lampetra fluviatilis (Linnaeus, 1758) (river lamprey) - jõesilm
Lampetra hubbsi (Vladykov & Kott, 1976) (Kern brook lamprey)
Lampetra lanceolata Kux & H. M. Steiner, 1972 (Turkish brook lamprey) – türgi silm
Lampetra lusitanica Mateus, Alves, Quintella & P. R. Almeida, 2013 – lusitaania silm
Lampetra pacifica (Vladykov, 1973) (Pacific brook lamprey) – columbia silm
Lampetra planeri (Bloch, 1784) (European brook lamprey) - ojasilm
Lampetra richardsonii (Vladykov & Follett, 1965) (western brook lamprey) - loodesilm
Lampetra soljani Tutman, Freyhof, Dulcic, Glamuzina & Geiger, 2017