Description from Flora of China
Dictyogramme Fée, nom. rej.
Plants terrestrial. Rhizomes decumbent or creeping, sparsely scaly; scales brown, lanceolate, margin entire. Fronds monomorphic, distant or closely spaced; stipe straw-colored or with brown spots, or chestnut-brown, glabrous distally, with a single U-shaped vascular bundle; lamina 1- or 2-imparipinnate, rarely trifoliate or 3-pinnate, sometimes entire in juvenile plants, usually herbaceous to papery, glabrous or with hairs on one or both surfaces. Pinnae usually ca. 5 pairs, stalked; in 1-pinnate species terminal pinna same as lateral pinnae; if 2-pinnate then only proximal pinnae imparipinnate or trifoliate (occasionally basal pair only bifurcate), and terminal pinna same as terminal pinnules of proximal pinnae. Pinnules (or distal simple pinnae) lanceolate or oblong-lanceolate, base rounded to cuneate, rarely cordate, margin entire or serrate. Veins free or rarely anastomosing near midrib, then free, vein tips enlarged forming hydathodes. Indusia absent. Sori along veins, intermixed with short, hairy paraphyses. Spores tetrahedral, plain. x = 30.
Morphologically, the species in the genus Coniogramme are poorly differentiated. Intermediate individuals exist in some groups, increasing the difficulty of discriminating species. On Emei Shan of Sichuan Province, juvenile plants of some species have simple, lanceolate, or trifoliate to 1-pinnate fronds, and only after several years of development are the fronds 2- or 3-pinnate. The stipe color is also variable, even in the same plant; some stipes are entirely green, and others have brownish purple spots abaxially. The following characters generally seem to be stable: glabrous or hairy lamina surfaces, hair form (jointed hairs or seta), lamina margin (entire or serrate), and the shape and location of the hydathodes (far from the tooth at lamina margin, extending into the teeth, or even fusing with the cartilaginous tooth margin). Further fieldwork and cytological study of the genus are still needed.
The fiddlehead of the species of Coniogramme is an edible vegetable, and the rhizome is known to store starch.
About 25-30 species: Africa, E and SE Asia, North America; 22 species (11 endemic) in China.
(Authors: Zhang Gangmin (张钢民); Tom A. Ranker)