Aesculus X carnea

This red-flowered cultivar of Aesculus sp. does not attract insects to pollinate it and thus it cannot reproduce itself. It is however a widespread decorative plant in European and North American cities.
Prague - Campa, May 14, 2013

Aesculus hippocastanum

 

The yellow dot on the flower turns red once it is fertilized.

Prague - Campa, May 14, 2013