Hemilophieae Al-Shehbaz, Hendriks, M.Koch, F.Lens, Lysak, C.D.Bailey, Mumm. & D.A.German, trib. nov. (2: 7)

German, Dmitry A., Hendriks, Kasper P., Koch, Marcus A., Lens, Frederic, Lysak, Martin A., Bailey, C. Donovan, Mummenhoff, Klaus & Al-Shehbaz, Ihsan A., 2023, An updated classification of the Brassicaceae (Cruciferae), PhytoKeys 220, pp. 127-144 : 127

Hemilophieae Al-Shehbaz, Hendriks, M.Koch, F.Lens, Lysak, C.D.Bailey, Mumm. & D.A.German, trib. nov. (2: 7)

Type.

Hemilophia Franch.

Description.

Herbs rhizomatous perennials. Trichomes simple, malpighiaceous, sometime short-stalked forked. Multicellular glands absent. Cauline leaves petiolate to subsessile and cuneate to attenuate at base, not auriculate. Racemes bracteate throughout, elongated or not in fruit. Flowers actinomorphic; sepals ascending to spreading, base of lateral pair not saccate; petals white, pink, or purple; claw obscurely differentiated from blade or distinct; filaments slender or dilated at base and sometimes strongly appendaged; pollen 3-colpate; ovules 2 or 4 per ovary, apical. Fruits dehiscent silicles, oblong to ovoid, terete or slightly angustiseptate, unsegmented, wingless or with narrow wings or crests; septum complete or absent; styles distinct, cylindrical or conical; stigma entire. Seeds aseriate; cotyledons accumbent. Base numbers various.

Distribution.

Endemic to China (Sichuan and Yunnan).

Note.

The tribe includes narrowly distributed monospecific Dipoma and Hemilophia (6 spp.).

3e. Idahoa and Subularia

Beilstein et al. (2006, 2008) studied two samples of Idahoa A. Nelson & J.F. Macbr. and their position was unresolved in a polytomy that included Asta Klotzsch ex O.E. Schulz and Cremolobeae ( Cremolobus DC. and Menonvillea DC.). Couvreur et al. (2010) sampled only Subularia L. but it was oddly placed in the Isatideae . By contrast, the family-wide phylogenetic study of Warwick et al. (2010) was the first that dealt with both Idahoa and Subularia . The former was sister clade to Petrocallis W.T. Aiton and together they were sister to Subularia . That clade was sister to many taxa of various tribes. These early studies did not resolve the relationship of both genera, and Al-Shehbaz (2012) listed both genera as unplaced.

The first clear relationship of Idahoa and Subularia to other tribes was given in Nikolov et al. (2019). The two genera formed a monophyletic group sister to a clade of Asta and Scoliaxon Payson ( Asteae ), which was sister to the South American CES clade of Salariato et al. (2016): Cremolobus ( Cremolobeae ), Brayopsis Gilg & Muschl. ( Eudemeae ), and Schizopetalon Sims ( Schizopetaleae ). The findings of Walden et al. (2020) and Dogan et al. (2022) were basically similar in terms of the entire complex of tribes except for minor differences in the position of Idahoa and Subularia relative to the other tribes. The findings of Hendriks et al. (2022) are basically the same except for the unexpected position of Teesdalia W.T. Aiton ( Iberideae ) between Subularia and Idahoa , and further studies should resolve such a relationship. Regardless of the slight differences in the most recent plastid vs. nuclear family-wide phylogenies, it is evident that these two genera should be placed in one tribe, and the name Subularieae was validly proposed over two centuries ago.