SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd560886d67a79798cad82f78a45085acb64e02bea6a013559a552f48bc1bcaeb' 
  AND token = 'KOjhBkEGG64HVysOalEti9LcxTAE7Lj9+Gg4YHBKSMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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