Ceratopteris shingii Y. H. Yan & R. Zhang, sp. nov. 2020
MycoBank
Holotype: CHINA, Hainan Province, Haikou City, Longhua District, Jiangjunshan, in some volcanic lakes, 19°47′N, 110°17′E, elev. 44 m, 12 January 2019. Yue-Hong Yan Fern09770 (holotype, CSH!; isotypes, CSH!, PE!, IBSC!).
Morphological description
Terrestrial and aquatic, 8.3–41 cm tall. Rhizomes: long-creeping to 1 m long, scaly. Scales sparse on stipe apex and dense on the base, brown, and hyaline. Fronds: dimorphic, green and fleshy, and distant with the spacing 1–2 cm; dormant bud initials are often found in the sinuses of the pinnae of both sterile and fertile fronds, and dropped when ripe. Sterile fronds: 8.3–24.2 cm long; stipes 3.5–8.5 cm long; blades 4.7–15.5 cm long, 2.6–5 cm wide; 2–3 pinnate; 4–10 pinnae pairs, ovate to oblong, up to 1 × 0.5 cm; terminal lobes entire, ovate to deltoid to oblong, 0.3–0.4 cm × ca. 0.1 cm; broad wing formed at the base of decurrent along rachis. Fertile fronds: 27.7–41 cm long; stipes 12.3–18.5 cm long; blades 15.5–22 cm long, 7–8 cm wide; three pinnate; 5–9 pinnae pairs, ovate to oblong, up to 22 × 7 cm; terminal lobes linear to siliquiform, 0.4–1.4 cm × ca. 0.1 cm. Spores: tetrahedral and trilete, 99–105 μm in diameter with parallel ridges on the surface. Tetraploid, 2n = ca. 154 (Fig. 2).
Habitat: in some volcanic lakes and even on dry volcanic rocks with elevation 44 m.
Distribution: Hainan Province, China.
GenBank Accession: rbcL MN316635; trnL(UAA)trnF(GAA) MN316636; psbCtrnS(UGA) MN316637; trnW(CCA)trnP(UGG) MN31664；rbcL-atpB MN316638
Notes: Morphologically, C. shingii is close to C. thalictroides, and associated cryptic species. It is characterized by its aquatic habit, unexpanded stipe bases, dimorphic fronds, linear sorus margins, and reflexed lobe margins. The rhizomes of all other Ceratopteris species are erect, whereas C. shingii has creeping rhizomes. In addition, our phylogenetic analysis revealed C. shingii as sister to all other Ceratopteris species.
Reference: RUI ZHANG1,2,6, JUN-HAO YU1,3,7, WEN SHAO1,8 et al.
Ceratopteris shingii Y.H. Yan & R. Zhang. Drawn by Wen Shao based on the holotype Fern 09770 (CSH). A. Habit; B. Enlarged fertile frond anatomy/portion for sporangium; C. Scale; D. Spore.
