9. Lindsaea orbiculata (Lamarck) Mettenius ex Kuhn, Ann. Mus. Bot. Lugduno-Batavi. 4: 279. 1869.
团叶鳞始蕨 tuan ye lin shi jue
Adiantum orbiculatum Lamarck, Encycl. 1: 41. 1783; Lindsaea commixta Tagawa; L. hainanensis Ching (1949), not L. hainaniana (K. U. Kramer) Lehtonen & Tuomisto (2010); L. orbiculata var. commixta (Tagawa) K. U. Kramer; L. simulans Ching; L. taiwaniana Ching; L. tenera Dryander var. commixta (Tagawa) K. Iwatsuki; Schizoloma intertextum Ching.
Rhizomes shortly creeping, sparsely scaly; scales appressed or spreading, castaneous, 2-4 cells wide at base, acicular at apex. Fronds approximate; stipe castaneous, 4-35 cm, quadrangular; lamina 9-25 × 1.5-15 cm, herbaceous to papery, 1- or 2-pinnate; if 1-pinnate then lamina linear, pinnae 10-22 pairs, dimidiate, rhomboid, flabellate, or orbicular, upper margin entire or erose in fertile pinnae or dentate in sterile pinnae, upper pinnae hardly or gradually reduced toward apex; if 2-pinnate then lamina with 1-5 pairs lateral pinnae, terminal pinna similar to or usually much larger than lateral ones, basal pinnae very small or fully developed; in 2-pinnate laminae, pinnules similar to those pinnae in 1-pinnate lamina but fewer, usually with 1-9 on each side of costa; veins free, evident. Sori marginal or submarginal, terminal on all veins; indusia linear, continuous, or rarely interrupted by incisions. 2n = 88*, ca. 300.
Terrestrial, forests; near sea level to 1200 m. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangxi, Sichuan, Taiwan, Yunnan, Zhejiang [India, Indonesia, Japan, Malaysia, Myanmar, Nepal, Philippines, Singapore, Sri Lanka, Thailand, Vietnam].
Lindsaea orbiculata is very variable, and it is possibly a complex. The typical form (stipes 5-10 cm, lamina 1-pinnate, pinnae orbicular or flabellate, and sori marginal, continuous) is found on the one hand, and on the other is the form known as L. hainanensis (stipes up to 28 cm, fully 2-pinnate, and pinnules rhomboid). The two forms appear very distinct, but there is a series of transitional specimens known. Two cytotypes, diploid and tetraploid, were reported for L. orbiculata. Further taxonomic studies at the population level of this taxon are needed.
Lindsaea flabellulata Dryander (Trans. Linn. Soc. London 3: 41. 1797), type from Macao, was treated as a synonym of L. orbiculata in FRPS (2: 264. 1959).