what are its earliest species?
UNANSWERABLE
what is african river martin? A passerine bird what is the origin and evolution of this former mentioned species? It is one of two members of the river martin subfamily of the swallow family, Hirundinidae.
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African river martin [SEP] Introduction
The African river martin ("Pseudochelidon eurystomina") is a passerine bird, one of two members of the river martin subfamily of the swallow family, Hirundinidae. When discovered, it was not initially recognised as a swallow, and its structural differences from most of its relatives, including its stout bill and robust legs and feet, have led to its current placement in a separate subfamily shared only with the Asian white-eyed river martin. The African river martin is a large swallow, mainly black with a blue-green gloss to the head and a greener tint to the back and wings. The under-wings are brownish, the underparts are purple-black, and the flight feathers are black.