SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9b2243989ff981182909fdf65dda410d0a3f5953ae7cab9164f1be60fbea91b' 
  AND token = 'Go/GvJW2RLNUUSRoS0FxPZdRrr2elykkV+zyo8eBqAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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