SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cf60a3ece32a282b43e5739829c1bd9f364e66ee99391a9f912ef75f45f7d10' 
  AND token = '5faCkbzMhGLEouvNklNqyDlPm/MMjI4EkA+tq/QHlTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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