SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d0721e2de8feb68f6e76f4babdc7f295590f41ceb9dbad04d4db01a95638348' 
  AND token = '3iv3/EIXWusGX9ZrJSor8FB8YAou7Oe+LATTKuRqFgo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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