Acanthogilia is a poorly known monotypic genus of spiny shrub endemic to Baja California. The sole species, A. gloriosa, is likely sister to the rest of Polemoniaceae.
Acanthogilia may be differentiated from all other Polemoniaceae by the presence of persistent, woody-spinose leaves with deciduous axillary leaves.
The phylogentic position Acanthogilia is currently unresolved as it forms a polytomy with the other woody Polemoniaceae: Bonplandia, Cantua, and Cobaea (Johnson et al. 2008). However, when its ecology, geography, and morphology are taken into consideration as addditional evidenceand compared with the the closest relative to the Polemoniaceae, Fouquieriaceae, the total evidence suggests that it is likely sister to the rest of Polemoniaceae. As with other “basal” Polemoniaceae, it shares a perennial woody habit, winged seeds, and free stamens. In addition, the pollen grains of Acanthogilia are very similar to those of Cantua in that they have very large verrucae in the exine (Day and Moran 1986). Similarly, fascicled leaves are also found in some species of Cantua.
Detailed comparative anatomical study of Acanthogilia and Fouquieira would be extraordinarily insightful.
Acanthogilia is endemic to Baja California
The genus contains only one species:
- Acanthogilia gloriosa (Brandegee) A.G. Day & Moran
Day, A. G., and R. Moran. 1986. Acanthogilia, a new genus of Polemoniaceae from Baja California, Mexico. Proceedings of the California Academy of Sciences 44: 111–126.