 They are protected by small indusia that are cup-like in appearance.Large and Braggins (2004) note that Rolla Tryon (1970) regarded "Alsophila arfakensis" as synonymous with this taxon, although it is still possible that they represent separate species., Plants of the World Online regards "Alsophila lilianiae" as a synonym of "Alsophila biformis", whereas the "Checklist of Ferns and Lycophytes of the World" regards them as separate species.