17. Dryopteris sect. Acrorumohra (H. Itô) Li Bing Zhang & H. He
假复叶耳蕨组 jia fu ye er jue zu
Authors: He Hai, Li-Bing Zhang & David S. Barrington
Basionym: Rumohra sect. Acrorumohra H. Itô, J. Jap. Bot. 11: 583. 1935; Acrorumohra (H. Itô) H. Itô.
Plants terrestrial, medium-sized. Rhizome erect, short, clothed with scales; scales linear to linear-lanceolate or ovate, margin entire. Fronds tufted; stipe base scales like those of rhizome, becoming glabrous above; lamina broadly lanceolate, ovate, or pentagonal, (2 or)3- or 4-pinnate; ultimate pinnules or segments obliquely ovate or elliptic, without aristate teeth along margin or at apices, basal acroscopic segment often slightly auriculate, ± adnate to axes. Lamina herbaceous or papery, subglabrous on both surfaces; veins free, veinlets simple or 1(or 2) times forked, ending short of margin, tip not enlarged; arrangements of pinnules, segments, and veins anadromous throughout. Sori orbicular, terminal on acroscopic veinlet branches (occasionally subdorsal on veinlets); indusia reniform and entire, or absent; sporangia numerous, without glands on axes, annulus of 14-17 thickened cells. Spores ellipsoid; surface lophate. x = 41.
About four or five species: tropical and subtropical areas of S and SE Asia, extending to the Pacific islands; three species (one endemic) in China.
Although Acrorumohra is sometimes treated as a separate genus, it is part of Dryopteris as resolved in a recent molecular study (Li Bing Zhang et al., BMC Evol. Biol. 12: 180. 2012).