SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13f77a9ae87a030667a8a64897377b295f62f506caf082b91111324eff73beb7' 
  AND token = '0XeEBChEvrFiUvlznxbW27wckl9WjV/5YQfQZ3YvG9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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