SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63dcf948dd797e19744294ac82ed6ad7bd3bd625853387dc171c4de7904e15b8' 
  AND token = 'pGoCSzYwuerr7YiVU/R+FBDYIFZyvMSOLgsEoPTicdk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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