Oxypolis denticulata (Baldwin) Raf.
Pastinaca ambigua (Nutt.) Torr.
Archemora rigidior var. ambigua (Nutt.) A.Gray
Oxypolis longifolia (Pursh) Small
Archemora rigidior (L.) DC.
Oxypolis tricuspidata (Elliott) Raf.
Oxypolis turgida Small
Tiedemannia rigidior var. ambigua (Nutt.) J.M.Coult. & Rose
Archemora denticulata (Baldwin) DC.
Archemora ambigua (Nutt.) DC.
Sium rigidius L.
Pastinaca denticulata (Baldwin) D.Dietr.
Sium denticulatum Baldwin
Tiedemannia rigidior (L.) J.M.Coult. & Rose
Oxypolis rigidior var. longifolia (Pursh) Britton
Pastinaca rigidior (L.) Spreng.
Oenanthe rigidius (L.) Crantz
Oxypolis rigidior var. ambigua (Nutt.) B.L.Rob.
Sium longifolium Pursh
Peucedanum rigidius (L.) Baill.
Archemora serrata Raf.
Sium tricuspidatum Elliott
Oenanthe ambigua Nutt.
Archemora tricuspidata (Elliott) DC.
Archemora trifoliata Raf.
Pastinaca tricuspidata (Elliott) D.Dietr.
Peucedanum rigidius var. ambiguum (Nutt.) Alph.Wood
Oxypolis rigidior subsp. longifolia (Pursh) W.Stone
Tiedemannia rigida (L.) J.M.Coult. & Rose