SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f0016b4bebfeda3d47656a677100f7fd7beb2d7e28e30c4394e978dc334d23b' 
  AND token = 'qsHhvM0pDMEYOwluCN6nWBka6ah49tlLGnQCx6tjIjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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