SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f11b14837d3311a92b68cc68000d582c2e6c5bf0df9525e15a48e7ebfc21e291' 
  AND token = '9KlCq57JTUl3dku5B3OBmn4sWXeBa2ISk5PkKKPzrfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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