SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3085ca318acc6301f23aeceb8fb85180ebf55be8a43c1687dd6eb1496275290d' 
  AND token = 'Xg9FJDWzmzrQrvRSktYG8sEk+lZEwGCl+2Ply4N2GzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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