SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bddc1521361f6e4d5fbfaa94d920500f8b599637cd1ed221f55f21119dcc4ab' 
  AND token = 'WfBvlG9fKCRmrgsTNrWSVgd1eMLFrk/U/gsa0T8Hy68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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