SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf13fdca9d2c04d1a5b92778fe6e418b6eb85aea0aa1417d58abb6f00951408b' 
  AND token = '5HV6/FZ4VdU4Lh+oDflLcSgD+zJmoustAcsrVYB2YJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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