SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db96f918192d40e650e7fdf26365e9eb78df5a127a9e6eb7d9b68530789665bc' 
  AND token = 'wUyVRgbG3muGhQkx4HWpnR1kx++j/WCRehMqznQoRYc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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