Neottia bifidus M.N.Wang, 2023

Wang, Mei-Na, Wu, Xin-Yi, Tan, Cheng-Jiang, Yu, Ping, Rao, Wen-Hui, Chen, Jie-Shan, Li, Jian & Chen, Jian-Bing, 2023, Neottia bifidus (Orchidaceae, Epidendroideae, Neottieae), a new mycoheterotrophic species from Guizhou, China, PhytoKeys 229, pp. 215-227 : 215

Neottia bifidus M.N.Wang sp. nov.

Figs 4 , 5 Chinese name: 鱼尾鸟巢兰

Type.

China. Guizhou Province, Qiannan Buyi and Miao Autonomous Prefecture , Libo County, the Maolan National Nature Reserve , 825 m elev., 23 April 2021, J.B.Chen 00599 (holotype: NOCC) .

Diagnosis.

Neottia bifidus is morphologically similar to N. nidus-avis , N. kiusiana and N. papilligera but differs in having a finely pubescent rachis, with fewer flowers; finely pubescent pedicel; and fish-tail-shaped lip, deeply 2-lobed to the centre of mid-lip, lobes diverging at an acute angle (45°) to one another, mesochile with many papilloses (Table 4 ).

Terrestrial herbs, leafless, holomycotrophic, 10-19 cm tall. Rhizome short, with many stout, fleshy fascicled roots. Stem erect, terete, leafless, pubscent, with 2-3 sheaths at base; sheaths tubular, 2-3 cm, membranous, glabrous, with 4-7 dark brown veins, upper ones much longer than lower ones; rachis 7-13 cm, pubscent, laxly and irregularly 9-15-flowered; floral bracts membranous, glabrous, narrowly lanceolate, ovate-lanceolate, obtuse to subacute, 0.7-2.1 cm long, lowermost ones much longer than flowers, 1.1-1.3 × 2.6-3 cm, gradually diminishing in upper ones which are shorter than ovaries. Flowers resupinate, pale brown; pedicel and ovary 0.6-1.5 cm long, pubescent. Sepals membranous, ovate to obovate, pale brown, nearly equal in size; dorsal sepal cucullate, 2.3-2.4 × 1.6-1.8 mm, apex obtuse, glabrous; lateral sepals cucullate, strongly cupped, 2.4-2.5 × 1.4-1.5 mm, apex obtuse, glabrous. Petals membranous, ovate to obovate, pale brown, nearly equal in size to dorsal sepal. Lip spreading downwards, subrectangular, 3.8-5 mm long, small and semi-transparent at early anthesis, becoming larger and yellowish-brown at late anthesis, apex deeply 2-lobed to the center of mid-lip; hypochile rectangular, concave at base; mesochile with many papilloses; epichile 2-lobed, lobes extending outwards, triangular, fish-tail-shaped, 2.3-2.5 × 1.5-1.6 mm, diverging at an acute angle (45°) to one another, apex obtuse, margins of apices and inner sides repand or erose. Column cylindrical, 2.8-3 mm long; anther inclined towards rostellum, elliptic, ca. 0.7 mm; stigma ca. 0.9 mm, lamellate, 2-lobed; rostellum shorter than anther. Capsule elliptic, with persistent sepals and petals, 1-1.5 cm long.

Etymology.

The species epithet refers to the fish-tail-shaped lip of the new species.

Distribution and habitat.

Neottia bifidus is currently known only from the type locality in Libo, Guizhou, China. It grows in humus-rich soil under broad-leaved forests at elevations of 700-900 m and is found growing with Miliusa sinensis Finet & Gagnep. ( Annonaceae ), Platycarya strobilacea Siebold & Zucc ( Juglandaceae ), Michelia martini (H. Lév.) Finet & Gagnep. ex H. Lév. ( Magnoliaceae ), Mallotus philippensis (Lamarck) Müll. Arg. ( Euphorbiaceae ), Symplocos adenophylla Wall. ( Symplocaceae ), Chimonobambusa angustifolia C. D. Chu & C. S. Chao ( Poaceae ), Murraya exotica L. ( Rutaceae ), Gomphandra tetrandra (Wall.) Sleumer ( Stemonuraceae ), Diospyros mollis Griff. ( Ebenaceae ), Strobilanthes hongii Y. F. Deng & F. L. Chen ( Acanthaceae ), etc.

Phenology.

Flowering and fruiting from Apr-May.

Conservation status.

During our fieldwork, only one population with less than 10 individuals was discovered in Maolan National Nature Reserves (213 km2). Most individuals were found growing along the roadside and are easily disturbed by human activities. According to the guidelines for using the IUCN Red List Categories and Criteria ( IUCN 2022), the new species should be temporarily assigned as 'Critically Endangered’ by its limited populations, localities and vulnerable habitats.

Note.

Neottia bifidus is morphologically - related to three species, namely, N. nidus-avis , N. kiusiana and N. papilligera , but it is readily distinguished from them, based on morphological characters given in Table 4 .

Figures

Figure 4. Neottia bifidus M. N. Wang, sp. nov. A whole plant B flower (front view) C flower (side view) D dorsal sepal E lateral sepal F petal G lip (front view) H bracts I ovary, column and lip (side view) J ovary and column (ventral view) K column L fruit with bract M fruit (cross section) N anther cap P hairy on rachis.

Figure 5. Neottia bifidus M. N. Wang, sp. nov. Photographed by M. N. Wang & W. H. Rao. A habit B whole plant and hairy on rachis C inflorescence D flower (front view) E ovary and flower (side view) and hairy on ovary F dorsal sepal G, H lateral sepals I, J petals K lip (front view, back view and side view) L bract M ovary and column N column O fruit with bract P fruit (cross section) Q Anther cap.