SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bd274f53aef9ef02f5908179169a3871980f4f864ff5284ea7927df0fce88e8' 
  AND token = 'Uw7uSlymBOpTRM9D0kX4ydUlEMgyI5WtHJtov0gdvDc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}