Calymmodon concinnus Parris, 2015

Parris, Barbara, Chen, Cheng Wei, Hsu, Tian Chuan, Lu, Thi Ngan, Nguyen, Quoc Dat & Luu, Hong Truong, 2015, New species and records of grammitid ferns (Polypodiaceae) for Vietnam, Phytotaxa 226 (1), pp. 39-50 : 40

Calymmodon concinnus Parris sp. nov. ( Figure 1 )

Calymmodon concinnus differs from other members of the genus in the following combination of characters; lamina less than 5 cm long, pinnae less than 20 pairs, sterile pinnae broadly triangular to broadly obovate, uppermost sterile pinnae shorter than the lowermost fertile pinnae, fertile pinnae not stalked; hydathodes at vein endings on the adaxial surface of the lamina; sori elliptic, in apical 1/6 to 3/4 of lamina, one row each side of rachis, 3–13 in each row, one per pinna; sporangia glabrous; 1–3-branched hairs with setae as branches present.

Type: — VIETNAM. Lam Dong Province: Lac Duong District , Da Chais Commune, Giang Ly, Salmon research center, elev. 1700 m, 26 December 2014, Hsu 7406 (holotype SGN!; isotype TAIF!) .

Rhizomes radial, stipes in whorls, not articulated to rhizome; stipes winged to base; laminae 16–35 × 3–5 mm, narrowly elliptic in outline, deeply pinnately divided to wing 0.1–0.2 mm wide along rachis, bluntly acute to obtuse at apex, long-attenuate at base; pinnae 6–16 pairs, uppermost sterile pinnae shorter than lowermost fertile pinnae, fertile pinnae 2–3 × 1 mm, folded acroscopically and protecting sori, narrowly triangular to narrowly oblong in outline, sterile pinnae 2–3 × 1–2 mm, broadly triangular to broadly oblanceolate; rachis level to slightly prominent on both surfaces, slightly darker on abaxial surface, concolorous to slightly darker on adaxial surface; veins simple, not extending beyond sori; vein endings with pale hydathodes on adaxial surface; 1–3-branched pale red-brown hairs with catenate base and setae as branches occasional to sparse on abaxial surface of rachis.

Distribution and habitat:—In mixed conifer-broadleaf forest along ridge. Endemic to Vietnam, only known from the type collection.

Etymology:—Latin, concinnus = neat, pretty, elegant, referring to the appearance of the fronds.

Taxonomic note:—The only other Calymmodon species with lamina less than 5 cm long, pinnae less than 20 pairs, lowermost fertile pinnae longer than uppermost sterile pinnae and only branched hairs present is C. mnioides Copel. from New Guinea. However, C. concinnus has unstalked fertile pinnae and broadly triangular to broadly oblanceolate sterile pinnae, while C. mnioides has stalked fertile pinnae and narrowly oblanceolate sterile pinnae.

Figures

FIGURE 1. Calymmodon concinnus—A. Habitat. B. Adaxial lamina. C. Abaxial lamina. D. Venation. E. Branched hairs. Scale bars: A = 1 cm, B, C, D = 1 mm, E = 0.1 mm.