Pseudolycopodiella subinundata (Tagawa) Li Bing Zhang, X.Wan, Ralf Knapp & H.He, comb. nov. Basionym: Lycopodium subinundatum Tagawa (1941: 75). Type:— JAPAN. Honshu: 1000–1500 m, T. Hasimoto 7291 (KYO). Lycopodium subinundatum was consistently treated as a synonym of Pseudolycopodiella caroliniana (Linnaeus 1753: 1101) Holub (1983: 442) (e.g., Ching 1982, Zhang & Kung 2000, Zhang 2004, Zhang & Iwatsuki 2013, Ebihara 2016). Based on our earlier molecular study, these two taxa were resolved as paraphyletic in relation to the Central and South American P. meridionalis (Underwood & Lloyd 1906: 121) Holub (1983: 442) (Chen et al. 2022). Lycopodium subinundatum and Pseudolycopodiella caroliniana are distributed in Asia and North America, respectively, and should be treated as different species. The former occurs in China, India, Japan, Malaysia, New Guinea, and Sri Lanka (Zhang & Kung 2000, Zhang 2004, Zhang & Iwatsuki 2013). In our earlier molecular work, we included only Japanese material of Pseudolycopodiella subinundata (Chen et al. 2022) which is assumed to be conspecific with the material from other parts of Asia. However, no molecular data from other parts of Asia are available. It is unknown whether the African material is assignable to the Asian species since no molecular data is available either. Pseudolycopodiella subinundata differs from P. caroliniana by having linear to linear-lanceolate dorsal leaves on the rhizome (vs. lanceolate dorsal leaves on the rhizome in the latter). In addition, the former has 2n = 68 (Takamiya & Kurita 1983), whereas the latter has 2n = 70, 140 (Wagner & Beitel 1993).

Published as part of Wan, Xia, Knapp, Ralf, Chen, De-Kui, He, Hai & Zhang, Li-Bing, 2023, Taxonomic notes on some East Asian pteridophytes, pp. 128-140 in Phytotaxa 597 (2) on page 129, DOI: 10.11646/phytotaxa.597.2.3, http://zenodo.org/record/7929279