Aptychus circinicaulis Müll. Hal. in Hedwigia 36: 125. 1897 .

Ξ Sematophyllum circinicaule (Müll. Hal.) Broth. in Nat. Pflanzenfam. (ed. 2) 11: 433. 1925.

Type citation. – “Paraguay, ‘bords du Mbay’, in truncis arborum, Julio 1881: B. Balansa in Coll. No. 3692 ”.

Type specimens. – Syntypes: Bords du Mbay, sur le tronc des arbres, juillet 1881, Balansa 3692 (G [1885], G00040506; Herb. Boiss., G00040496; Herb. Boiss., G00040497; Herb. DC. [1884], G00040505) [published in BESCHERELLE, 1885: 19] .

Type designation. – None found.