Vestured pits in Malvales s.l.: a character with taxonomic significance hidden in the secondary xylem

The distribution of vestured pits in the secondary xylem of all major group s of Malvales s.l. is investigated and compared with recent circumscription s and phylogenetic insights of the order. While the monophyly of the core M alvales, including Bombacaceae, Malvaceae s.str., Sterculiaceae, and Tiliac eae, is supported by the lack of vestured pits, the character is consistent ly present in three malvalean alliances that are well supported based on mo lecular data: (1) Bixaceae, Cochlospermaceae, and Diegodenduareae; (2) Cist aceae, Dipterocarpaceae s.l. (including Monotaceae), and Sarcolaenaceae; an d (3) Thymelaeaceae s.l. (including Aquilariaceae and Gonystylaceae). Vestu red pits are absent in other malvalean taxa such as Petenaea. Muntingiaceae , Neuradaceae, and Sphaerosepalaceae. Families that are now excluded from t he order, such as Dirachmaceae, Elaeocarpaceae, and Huaceae also have non-v estured pits. Rudimentary vestures in Plagiopteraceae, however, do not nece ssarily indicate a malvalean affinity.