SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f220e0bb395284c279f65d05a50b3888fa421edff989b2d368f3164b4ab4167' 
  AND token = 'Ef+/3zUTKXg0cqtNEvcWxwaZ30N3uxYQZt6QmVCormc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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