SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13cf141a73156ed988d9bf46d333c33ccc5c8795171996a59cb833382cd70591' 
  AND token = 'f12HoOgl92fkA6f9dqLPBnA8/Y4zvUH+QxemZ3hFK+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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