SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '014f5df162dbe30384b763f98d412695e22dbfcaf49db36280df5bbb51f69487' 
  AND token = '/WRnUszFIVB9+CJGYdAPfiexNyffOFsM3/wY9H7bPWE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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