SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '140c6ba1b88e4409bfb87ce5829e43b9b7383db6fbdab81f5dc70177cbf3ba36' 
  AND token = 'Ginr3HPQwhlnqgxfYmh3QWSULMMisvrqqJvMlpC5c+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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