SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc3de7663ee7337f2ccbea3d7890a7f190351d88c281aa6021dea3d871059ab5' 
  AND token = 'rNQXsJHvnQV26wP09QiH2olkgQ38cOYOHviNx3eSg2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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