SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af2384b064db48d1b74db4a8f47e474d26fe9dcd408d28b93bf25b315048c5bd' 
  AND token = 'YvuvqGfXZOwA/woJrwWe+6jLdW92bsNWHMZZ+xfaSzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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