6. Bombax marginatum f. apaense Hassl. in Repert. Spec. Nov. Regni Veg. 8: 70. 1910.

Holotypus: PARAGUAY. Concepción: “In dumetis prope Rio Apa”, V.1885 -1895, Hassler, E. 410 (G [G00307102]! [lf, fl]) . Isotypi: (G [G00307100]! [fl], G [G00307101]! [fl], K! [fl], NY [NY00133529]! [fl], NY [NY00133530]! [fl], P [P06622878]! [fl], P [P06622882]! [fl]) .

The specimen [G00307102] has not been annotated as form apaense by Hassler, but it is the only one with leaf and flowers and thus the only specimen matching the protologue. The specimen [G00307101] was annotated by Hassler but it does not include any leaf material.

The form apaense is included in B. marginatum var. arboreum (Chodat) Hassl. and Hassler 410 is also the lectotype of its basionym B. marginatum f. arboreum Chodat.