Series Echinatae J.C.Manning & Klak, ser. nov.
Type: T. echinata Aiton.
Prostrate ± annual herbs. Flowers sessile or subsessile, solitary or in small groups. Stamens as many as and alternating with perianth segments, sometimes in pairs, or sometimes fewer. Ovary halfinferior. Fruit not winged, often with ridges or projections at top or sides.
Species: T. acanthocarpa Adamson, T. caesia Adamson, T. echinata Aiton, T. microptera Fenzl
Note: The accession identified as ‘ T. microptera (voucher Klak 2430, BOL)’ in Klak et al. (2017)