| Popis: |
By combining information on host ranges, biogeography, and paleoclimatology with detailed morphology, some progress has been made in understanding Raveneliaceae. Two tribes, Ravenelieae and Uropyxideae, are recognized. However, a few genera cannot be firmly assigned to a tribe, although plainly raveneliaceous, having type 5 or type 7 pycnia. By maintaining the broad family concept, all genera are at least assignable to a family. The family Pileolariaceae of Cummins and Hiratsuka is unacceptable: Pileolaria, on Anacardiaceae, is evidently allied to Uropyxideae; but Uromycladium and Atelocauda, both rusts of Acacia, belong in Ravenelieae with the other Acacia rusts. Ravenelieae evolved with Mimosoideae, mainly in the Neotropics, and all species are autoecious. Although Uropyxideae is predominantly tropical and autoecious, Tranzschelia and Leucotelium are north temperate and heteroecious. All genera of Uropyxideae are morphologically advanced. It is deduced that the early genera were heteroecious and were eradicated in times of severe aridity that broke the associations of the alternate hosts. Sphaerophragmiaceae is polyplyletic and cannot be maintained. |
