SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72df22f4cfeab55d623228cce5a807aec0bf3b8bb21094c71bb6da7113b2ab74' 
  AND token = '+hOCHxRisYgWJkDvsr7eRZrrTI0hyXTCzGcT/74kXD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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