SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '228c9f75dcdfc0f04ae625a7e8451d866f8dcd90736cecffbf09811a836b3d69' 
  AND token = 'SWFBDTfxs4u3eQuAEQ4d7jqiEZIpBIUo01C19zz7bXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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