SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df872927768eaaa3584b9519877c910c06445d195d68bf9cce5ae338fb438edb' 
  AND token = 'GIadqx2eSe35kgIq1DnRqo1YYJSIqLoxN8952K2dQ6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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