SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ad59b9b08878fe64f67f0cfda5b93fa926a3c1037b47d982e737564ab534d1c' 
  AND token = 'lfyD891GYE9OX7JJ7FW2X6l1grOcGGZKFTELEfNNy3I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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