• Senecio Linnaeus, 1753
• Senecio actinella Greene
• Senecio acutidens Rydb. accepted as Packera streptanthifolia (Greene) W.A. Weber & A. Löve
• Senecio adamsii T.J. Howell accepted as Packera streptanthifolia (Greene) W.A. Weber & A. Löve
• Senecio admirabilis Greene accepted as Senecio serra Hook.
• Senecio alabamensis Britt. ex Small accepted as Packera tomentosa (Michx.) C. Jeffrey
• Senecio alaskanus Hultén accepted as Tephroseris yukonensis (Porsild) Holub
• Senecio ambrosioides Rydb. accepted as Senecio eremophilus Richards.
• Senecio amplectens Gray
• Senecio ampullaceus Hook.
• Senecio anonymus Wood accepted as Packera anonyma (Wood) W.A. Weber & A. Löve
• Senecio antennariifolius Britt. accepted as Packera antennariifolia (Britt.) W.A. Weber & A. Löve
• Senecio aphanactis Greene
• Senecio argutus A. Rich. accepted as Erechtites glomerata (Desf. ex Poir.) DC.
• Senecio arizonicus Greene
• Senecio aronicoides DC.
• Senecio astephanus Greene
• Senecio atratus Greene
• Senecio atropurpureus (Ledeb.) Fedtsch. accepted as Tephroseris atropurpurea (Ledeb.) Holub
• Senecio aureus Linnaeus accepted as Packera aurea (L.) A. & D. Löve
• Senecio balsamitae Muhl. ex Willd. accepted as Packera paupercula (Michx.) A. & D. Löve
• Senecio bernardinus Greene accepted as Packera bernardina (Greene) W.A. Weber & A. Löve
• Senecio bicolor (Willd.) Todaro
• Senecio bigelovii Gray
• Senecio bivestitus Cronq. accepted as Tephroseris lindstroemii (Ostenf.) A. & D. Löve
• Senecio blitoides Greene accepted as Senecio fremontii Torr. & Gray
• Senecio blochmaniae Greene
• Senecio bolanderi Gray accepted as Packera bolanderi (Gray) W.A. Weber & A. Löve
• Senecio breweri Burtt-Davy accepted as Packera breweri (Burtt-Davy) W.A. Weber & A. Löve
• Senecio cacalioides Fisch. ex Spreng. accepted as Erechtites hieraciifolia (L.) Raf. ex DC.
• Senecio californicus DC.
• Senecio cannabifolius Less.
• Senecio cannabinifolius Hook. & Arn.
• Senecio canus Hook. accepted as Packera cana (Hook.) W.A. Weber & A. Löve
• Senecio capillaris Gaud. accepted as Tetramolopium capillare (Gaud.) St. John
• Senecio cardamine Greene accepted as Packera cardamine (Greene) W.A. Weber & A. Löve
• Senecio carlomasonii B.L. Turner & T.M. Barkl. accepted as Roldana hartwegii (Benth.) H.E. Robins. & Brett.
• Senecio carthamoides Greene accepted as Senecio fremontii Torr. & Gray
• Senecio castoreus Welsh accepted as Packera castoreus (Welsh) Kartesz
• Senecio cernuus Gray accepted as Senecio pudicus Greene
• Senecio cineraria DC. accepted as Senecio bicolor (Willd.) Todaro
• Senecio clarkianus Gray
• Senecio cleavelandii Greene
• Senecio clevelandii Greene accepted as Packera clevelandii (Greene) W.A. Weber & A. Löve
• Senecio clivorum Maxim.
• Senecio columbianus Greene accepted as Senecio integerrimus Nutt.
• Senecio confusus Britten accepted as Pseudogynoxys chenopodioides Kunth
• Senecio congestus (R. Br.) DC.
• Senecio conterminus Greenm. accepted as Packera contermina (Greenm.) T.M. Barkl.
• Senecio convallium Greenm. accepted as Packera cana (Hook.) W.A. Weber & A. Löve
• Senecio covillei Greene accepted as Senecio scorzonella Greene
• Senecio crassulus Gray
• Senecio crawfordii (Britt.) G.W. Douglas & G. Ruyle-Douglas accepted as Packera paupercula (Michx.) A. & D. Löve
• Senecio crepidineus Greene accepted as Senecio elmeri Piper
• Senecio crocatus Rydb. accepted as Packera crocata (Rydb.) W.A. Weber & A. Löve
• Senecio cruentus DC. accepted as Pericallis cuneata (L'Hér.) Bolle
• Senecio cymbalaria Pursh accepted as Packera cymbalaria (Pursh) W.A. Weber & A. Löve
• Senecio cymbalarioides Buek accepted as Packera cymbalarioides (Buek) W.A. Weber & A. Löve
• Senecio cymbalarioides Nutt. accepted as Packera streptanthifolia (Greene) W.A. Weber & A. Löve
• Senecio cynthiodes Greene
• Senecio cynthioides Greene accepted as Packera cynthioides (Greene) W.A. Weber & A. Löve
• Senecio debilis Nutt. accepted as Packera debilis (Nutt.) W.A. Weber & A. Löve
• Senecio densus Greene accepted as Packera tridenticulata (Rydb.) W.A. Weber & A. Löve
• Senecio dimorphophyllus Greene accepted as Packera dimorphophylla (Greene) W.A. Weber & A. Löve
• Senecio discoideus (Hook.) Britt. accepted as Packera pauciflora (Pursh) A. & D. Löve
• Senecio douglasii DC. accepted as Senecio flaccidus Less.
• Senecio elegans Linnaeus
• Senecio elmeri Piper
• Senecio eremophilus Richards.
• Senecio ertterae T.M. Barkl.
• Senecio erucifolius Linnaeus
• Senecio eurycephalus Torr. & Gray ex Gray accepted as Packera eurycephala (Torr. & Gray ex Gray) W.A. Weber & A. Löve
• Senecio eurypterus Greenm. accepted as Packera neomexicana (Gray) W.A. Weber & A. Löve
• Senecio exaltatus Nutt. accepted as Senecio integerrimus Nutt.
• Senecio fedifolius Rydb. accepted as Packera debilis (Nutt.) W.A. Weber & A. Löve
• Senecio fendleri Gray accepted as Packera fendleri (Gray) W.A. Weber & A. Löve
• Senecio filifolius Nutt. accepted as Senecio flaccidus Less.
• Senecio flaccidus Less.
• Senecio flavulus Greene accepted as Packera pseudaurea (Rydb.) W.A. Weber & A. Löve
• Senecio flettii Wieg. accepted as Packera flettii (Wieg.) W.A. Weber & A. Löve
• Senecio flocciferus DC. accepted as Malacothrix floccifera (DC.) Blake
• Senecio foetidus J.T. Howell accepted as Senecio hydrophiloides Rydb.
• Senecio franciscanus Greene accepted as Packera franciscana (Greene) W.A. Weber & A. Löve
• Senecio fremontii Torr. & Gray
• Senecio frigidus (Richards.) Less. accepted as Tephroseris atropurpurea (Ledeb.) Holub
• Senecio fulgens Rydb. accepted as Packera streptanthifolia (Greene) W.A. Weber & A. Löve
• Senecio fuscatus auct. non Hayek accepted as Tephroseris lindstroemii (Ostenf.) A. & D. Löve
• Senecio ganderi T.M. Barkl. & Beauchamp accepted as Packera ganderi (T.M. Barkl. & Beauchamp) W.A. Weber & A. Löve
• Senecio gaspensis Greenm. accepted as Packera paupercula (Michx.) A. & D. Löve
• Senecio gibbsonsii Greene accepted as Senecio triangularis Hook.
• Senecio glabellus Poir. accepted as Packera glabella (Poir) C. Jeffrey
• Senecio glaucifolius Rydb. accepted as Senecio eremophilus Richards.
• Senecio glaucus L.
• Senecio glomeratus Desf. ex Poir. accepted as Erechtites glomerata (Desf. ex Poir.) DC.
• Senecio gracilis Pursh accepted as Packera aurea (L.) A. & D. Löve
• Senecio greenei Gray accepted as Packera greenei (Gray) W.A. Weber & A. Löve
• Senecio greggii Rydb. accepted as Packera tampicana (DC.) C. Jeffrey
• Senecio hallii Britt. accepted as Packera cana (Hook.) W.A. Weber & A. Löve
• Senecio harbourii Rydb. accepted as Packera cana (Hook.) W.A. Weber & A. Löve
• Senecio harfordii Greenm. accepted as Packera bolanderi (Gray) W.A. Weber & A. Löve