Didymoglossum henzaianum (Parish ex Hook.) Mazumdar

Didymoglossum henzaianum (Parish ex Hook.) Mazumdar View in CoL , Phytotaxa 158: 297, 2014.

Figs 4 View Figure 4 , 6 G – I View Figure 6

Type.

Myanmar • Mawlamyine, Henzai basin , C. S. P. Parish 5 (holotype: K [ K 000974336 ]; isotype: BM [ BM 001073866 , photo seen], GH) .

Diagnosis.

This species is frequently misidentified as D. sublimbatum (Fig. 6 J – L View Figure 6 ), but D. henzaianum has notably smaller fronds, typically about 1.5 cm long. The sterile fronds are round or linear, while fertile fronds range from ovate to spatulate. In contrast, D. sublimbatum has larger fronds (usually 2–3 cm long) that are oblong to lanceolate.

Description.

Rhizomes: long, creeping, slender, densely covered with short brown hairs. Stipes: very short, less than 2 mm long, terete in basal portion, sparsely covered with dark brown multicellular hairs. Fronds: entire to slightly lobed, with various shapes, round to ovate or linear to spatulate, 0.5–2 cm long, 0.5 cm broad, moderately acute to round at apex, cuneate at base, margin entire or slightly undulate. False veinlets: many, long, some false veins connected to main veins, usually 5–8 cells between adjacent false veins, apex of false veins usually falcate, forming sub-parallel to margin and connected to upper ones but not continuous. Sori: solitary, sunk in the apical segment, usually 1–2 sori per frond. Involucres: obconic, broadly dilated at the mount of involucres. Receptacles: filiform, long exserted.

Distribution and habitat.

India, Myanmar, Vietnam, Thailand, and Malesia (Peninsular Malaysia). Epilithic near streams.

Additional specimens examined.

Thailand • Loei: Phu Ruea District , 31 Aug. 2020, S. Chokrassameehirun 20-22 ( BKF) ; Kanchanaburi: “ Klawng Wa , ” 24 Dec. 1928, A. F. G. Kerr 16321 ( BK) ; Surat Thani: Phanom District , 16 Oct. 2023, S. Chokrassameehirun 24-105 ( BKF) .