SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed4558fe43af5a7c33125648360c9821c9c955bc2570249447423c7bbd80c8a7' 
  AND token = '3aLL6lJJxGRDdHG1FXkF1BnCYOJtKasXR1/v6ltu2hY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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