Similar Asian forms
...erythropygia a particularly distinctive form, perhaps worthy of specific status...
Type locality and taxonomy
...The Indian form erythropygia may also warrant elevation to species status (Rasmussen & Anderton 2005), as may one or two African forms. On the other hand, there still remains some disquiet as to whether Striated Swallow is a valid split...
...That a set of plumage and size differences exist by which rufula is diagnosably different from the Asian forms begs the obvious question: should they be split? As their breeding ranges are completely separate, there is unlikely to be any significant gene flow between rufula and daurica, and this is reflected in the fact that the plumage differences are quantifiable. A robust suite of identification characters is outlined above. This is less the case when differentiating the Asian forms from each other, where identification is primarily reliant on size and colour saturation. The visual clues by which rufula can be told from the Asian forms of Red-rumped Swallow are certainly more convincing than the differences between the Asian forms of Red-rumped Swallow and the neighbouring forms of Striated Swallow, yet these are regarded by many authorities as separate species. A re-examination of the Red-rumped Swallow complex is clearly overdue...
