Acanthophyton Less. accepted as Cichorium L. (original description)
Acanthophyton spinosum (L.) Less. accepted as Cichorium spinosum L. (original description)
Achyrocline Less. (original description)
Achyropappus pedatus (Cav.) Less. accepted as Florestina pedata (Cav.) Cass. (original description)
Adenostemma biflorum (L.) Less. accepted as Wollastonia biflora (L.) DC. (original description)
Ageratinae Less. (original description)
Ageratum matricarioides (Spreng.) Less. accepted as Phania matricarioides (Spreng.) Griseb. (original description)
Alibum Less. accepted as Munnozia Ruiz & Pav. (original description)
Alibum liaboides Less. accepted as Munnozia liaboides (Less.) H.Rob. (original description)
Allocarpus sabaoioides Less. accepted as Sabazia sarmentosa var. sarmentosa (original description)
Alomiinae Less. (original description)
Amberboa (Pers.) Less. (original description)
Amberboa glauca Less. accepted as Amberboa glauca (Puschk. ex Willd.) Muss.Puschk. ex Grossh. (original description)
Amberboa moschata Less. (original description)
Anaxeton arborescens (L.) Less. (original description)
Anaxeton hirsutum (Thunb.) Less. (original description)
Anaxeton nycthemerum Less. (original description)
Apargia hyoseridifolia Less. accepted as Crepis terglouensis (Hacq.) A.Kern. (original description)
Aposeris foetida (L.) Cass. ex Less. (original description)
Aposeris lucida (L.) Less. accepted as Hyoseris lucida L. (original description)
Apuleia atractyloides Less. accepted as Stobaea atractyloides Thunb. (original description)
Apuleia heterophylla Less. accepted as Berkheya heterophylla (Thunb.) O.Hoffm. (original description)
Apuleia zeyheri Less. accepted as Berkheya zeyheri (Sond. & Haw.) Harv. & Sond. (original description)
Arctotis amplexicaulis Less. (original description)
Artemisia subg. Seriphidium Besser ex Less. (original description)
Astemma Less. accepted as Monactis Kunth (original description)
Astemma dubium (Kunth) Less. accepted as Monactis dubia Kunth (original description)
Aster adfinis Less. accepted as Felicia dubia Cass. (original description)
Aster caffrorum Less. accepted as Microglossa caffrorum (Less.) Grau (original description)
Aster capensis Less. accepted as Felicia aethiopica (Burm.f.) Bolus & Wolley-Dod ex Adamson & T.M.Salt (original description)
Aster charieis Less. accepted as Felicia ovata (Thunb.) Compton (original description)
Aster crenatus (Thunb.) Less. accepted as Mairia crenata (Thunb.) Nees (original description)
Aster echinatus (Thunb.) Less. accepted as Felicia echinata (Thunb.) Nees (original description)
Aster ecklonis Less. accepted as Felicia aethiopica subsp. ecklonis (Less.) Grau (original description)
Aster maximus (D.Don) Less. accepted as Leptostelma maximum D.Don (original description)
Aster mespilifolius Less. accepted as Microglossa mespilifolia (Less.) B.L.Rob. (original description)
Aster perezioides (Nees) Less. accepted as Zyrphelis perezioides (Less.) G.L.Nesom (original description)
Aster zeyheri Less. accepted as Felicia zeyheri subsp. zeyheri (Less.) Nees (original description)
Asteriscus aquaticus (L.) Less. (original description)
Asteriscus graveolens (Forssk.) Less. (original description)
Asteriscus maritimus (L.) Less. accepted as Pallenis maritima (L.) Greuter (original description)
Asteropsis Less. (original description)
Asteropsis macrocephala Less. accepted as Asteropsis megapotamica (Spreng.) Marchesi (original description)
Asterosperma Less. accepted as Felicia Cass. (original description)
Asterosperma chrysocomoides Less. (original description)
Athrixia heterophylla (Thunb.) Less. (original description)
Athrixia tomentosa (Thunb.) Less. accepted as Amphiglossa tomentosa (Thunb.) Harv. accepted as Pterothrix tomentosa (Thunb.) DC. (original description)
Baillieria commelinoides Less. accepted as Ichthyothere cunabi Mart. (original description)
Bellidiastrum Less. (original description)
Bellidiastrum osmitoides Less. accepted as Osmitopsis osmitoides (Less.) K.Bremer (original description)
Berkheya eryngiifolia Less. accepted as Heterorhachis aculeata (Burm.f.) Roessler (original description)
Berkheya pinnata (Thunb.) Less. accepted as Heterorhachis aculeata (Burm.f.) Roessler (original description)
Blennosperma Less. (original description)
Blennosperma chilense Less. (original description)
Brachylaena elliptica (Thunb.) Less. (original description)
Brachylaena racemosa (Thunb.) Less. accepted as Brachylaena ilicifolia (Lam.) E.Phillips & Schweick. (original description)
Brachyrhynchos Less. accepted as Senecio L. (original description)
Brachyrhynchos elongatus Less. accepted as Senecio diversifolius Harv. (original description)
Brachyrhynchos eupatorioides Less. accepted as Senecio othonniflorus DC. (original description)
Brachyrhynchos junceus Less. accepted as Senecio junceus (DC.) Harv. (original description)
Breea Less. accepted as Cirsium Mill. (original description)
Breea arvensis (L.) Less. accepted as Cirsium arvense (L.) Scop. (original description)
Breea dioica (Cass.) Less. accepted as Cirsium arvense (L.) Scop. (original description)
Breea praealta Less. accepted as Cirsium arvense (L.) Scop. (original description)
Calea leontophthalmum Less. accepted as Calea peruviana (Kunth) Benth. ex S.F.Blake (original description)
Calea subg. Haplocalea Less. (original description)
Calea subg. Monanthocalea Less. (original description)
Carduncellus caeruleus (L.) Less. (original description)
Carelia Less. accepted as Radlkoferotoma Kuntze (original description)
Carelia cistifolia Less. accepted as Radlkoferotoma cistifolia (Less.) Kuntze (original description)
Carlina gummifera (L.) Less. (original description)
Carlina macrocephala Less. accepted as Carlina gummifera (L.) Less. (original description)
Cenia discoidea Less. accepted as Cotula nudicaulis Thunb. (original description)
Cenia subheterocarpa Less. accepted as Lancisia turbinata Gaertn. (original description)
Centipeda capensis Less. accepted as Dichrocephala integrifolia subsp. integrifolia (L.f.) Kuntze (original description)
Centrachaena Less. (original description)
Centrospermum humile (Sw.) Less. accepted as Acanthospermum humile (Sw.) DC. (original description)
Cephalophora heterophylla (Juss.) Less. accepted as Helenium radiatum (Less.) Seckt (original description)
Cephalophora subg. Actinella Less. (original description)
Cercostylos Less. accepted as Gaillardia Foug. (original description)
Cercostylos brasiliensis (Less.) Less. (original description)
Ceruana fruticosa Less. accepted as Ceruana pratensis Forssk. (original description)
Chaetantera Less. (original description)
Chaetanthera affinis Poepp. ex Less. (original description)
Chaetanthera berteroana Less. (original description)
Chaetanthera kunthiana Less. (original description)
Chaetanthera limbata (D.Don) Less. (original description)
Chaetanthera linearis Poepp. ex Less. (original description)
Chaetanthera linifolia Bertero ex Less. (original description)
Chaetanthera moenchioides Less. (original description)
Chaetanthera tenella Less. (original description)
Chlamydophora Ehrenb. ex Less. (original description)
Chlamydophora tridentata (Delile) Ehrenb. ex Less. (original description)
Chlamysperma Less. accepted as Villanova Lag. (original description)
Chlamysperma pratense (Kunth) Less. accepted as Galeana pratensis (Kunth) Rydb. (original description)
Chrysanthemum lidbeckioides Less. accepted as Osteospermum pinnatum var. pinnatum (Thunb.) Norl. (original description)
Chrysophania Kunth ex Less. accepted as Zaluzania Pers. (original description)
Chrysophania fastigiata Kunth (original description)
Chrysostemma Less. accepted as Coreopsis L. (original description)
Chrysostemma tripteris (L.) Less. accepted as Coreopsis tirpteris (original description)