Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a39692603bffe4237b554e3c51b4635e5a43c72f17704d2b2811f693d801d0d5' 
  AND token = 'ZmlBQ0ciLTL3fGxCCL39EXFY7+Fwm0Eb49eZsT5vrnc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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