Eupatorium liatrideum var. rubricaulis Arechav. accepted as Chromolaena squarrulosa (Hook. & Arn.) R.M.King & H.Rob. (original description)
Eupatorium serratum var. subglabra Arechav. accepted as Grazielia serrata (Spreng.) R.M.King & H.Rob. (original description)
Helianthus montevidensis Spreng. ex Arechav. (original description)
Hysterionica gracilis var. pilosa Arechav. (original description)
Mikania thapsoides var. incisa Arechav. (original description)
Mikania thapsoides var. robusta Arechav. (original description)
Podocoma hirsuta var. macrophylla Arechav. accepted as Podocoma hirsuta (Hook. & Arn.) Baker (original description)
Pterocaulon polystachyum var. tomentosa Arechav. accepted as Pterocaulon balansae Chodat (original description)
Pterocaulon virgatum f. alopecuroides (Lam.) Arechav. accepted as Pterocaulon alopecuroides (Lam.) DC. (original description)
Pterocaulon virgatum f. angustifolia Arechav. accepted as Pterocaulon lorentzii Malme (original description)
Pterocaulon virgatum f. subcorymbosa Arechav. accepted as Pterocaulon alopecuroides (Lam.) DC. (original description)
Pterocaulon virgatum f. subpaniculata Arechav. accepted as Pterocaulon balansae Chodat (original description)
Pterocaulon virgatum f. subvirgata (Malme) Arechav. accepted as Pterocaulon virgatum (L.) DC. (original description)
Senecio crassiflorus var. andryaloides (DC.) Arechav. accepted as Senecio crassiflorus (Poir.) DC. (original description)
Senecio icoglossoides Arechav. (original description)
Solidago microglossa var. ramosa Arechav. (original description)
Stevia entreriensis Hieron. ex Arechav. (original description)
Vernonia flexuosa var. glabra Arechav. (original description)
Vernonia nitidula var. lucida (Less.) Arechav. accepted as Vernonanthura lucida (Less.) H.Rob. (original description)
Vernonia rubricaulis var. dentata Arechav. (original description)
Vernonia rubricaulis var. floribunda Arechav. (original description)
Vernonia verbascifolia var. laxa Arechav. (original description)
Vernonia verbascifolia var. robustior Arechav. (original description)