SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca15e3cafa45d47bd5c9f8c49f6681659f213a2938a676d763ea8deb2afc9909' 
  AND token = 'NoBzjpS/3s1OgTXJLN3qIYwR5P6EXv80xV3gT2DWIsU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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