SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '432681a6da50c63ad034bb11487917cfc70395d9ac6649b86f6db2f9578a7c0c' 
  AND token = 'd5BKBkWkLtEucHQ3zZ/oWQ1uvOUVljuHWCIrAdBraEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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