SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd80771efd7e354edfd71430484ddc9dd94118466f342e8210db2771eedadd33' 
  AND token = 'Fe8s10iEv9MnutiDJfk5jCfe3qUhAzi3Ce4i8BgB2EY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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