SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44caceab43fe05d59f9132257633445972b393e880e034154b978e7037a23b1c' 
  AND token = 'fF+mtntV+JEkKUZC796BAhjI8QtvAcqwYjl3x0Ctlg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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