Pseudoliparis twardowskiana Margonska 2024, sp. nov.
Creators: name: Margońska, Hanna B.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Asparagales
Orchidaceae
Pseudoliparis
Pseudoliparis twardowskiana

description: Pseudoliparis twardowskiana Margońska, sp. nov. (Figs 1,2)
Type:— PAPUA NEW GUINEA. Eastern Highlands: Arau, 1400 m, collected by the 6th Archbold Expedition, 12 Oct. 1959, Brass L. J. 32020 (holotype: L 53991!).
The new species is easily distinguished by its characteristic apical gynostemium ornamentation, two symmetrical appendages (below anther base), which are erect, suborbicular and gently flattened. Its habit and floral elements seems to be similar to Pseudoliparis moluccana (Smith 1900: 2) Margońska (2003b: 63.; sect. Oistochilus, without of any column appendages) but can be easily distinguished by its floral morphology, e.g., narrower petals, flat lip lamina, abbreviated lip auricles and two well-developed, suborbicular gynostemium appendages.
Terrestrial herbs, 15–16 cm tall (including inflorescences). Rhizome cm long, 0.03–0.50 cm in diameter, creeping, covered by scales or their remains. Pseudobulbs 2.00–3.00 × 0.20–0.45 cm, with 2–3 basal scales. Leaves 3–6, the younger larger and more oblong than the others, (1.0)1.5–4.0 × (0.7) 1.2–1.8 cm, oblong ovate to lanceolate, falcate, distinctly apically attenuate, usually trinerved, margins crinkled; petiole 0.50–1.20 × 0.25–0.55 cm (when spread); leaf sheaths 0.4–1.0 cm long, 0.3–0.6 cm in diameter. Inflorescence 12–15 cm long, ca. 10–20-flowered. Sterile bract 1, recurved. Floral bracts up to 6 mm long, recurved. Flowers ca. 8–9 mm in diameter, green. Sepals trinerved. Dorsal sepal 5.0–5.6 × 2.0– 2.3 mm, oblong ovate to oblong, obtuse to subapiculate, basally nearly cordate. Lateral sepals 4.82–5.40 × 2.30–2.60 mm, oblique, ovate, obtuse to subapiculate, basally cordate. Petals 4.1–4.3 × 1.9– 2.1 mm, oblong elliptic, apically and basally slightly attenuate, gently falcate, 1-nerved. Lip 4.1–4.4 × 2.1–2.4 cm at widest basal part, obscurely sagittate in outline, generally flat, only around central part of base softly concave; midlobe semiovate, apiculate apically; lateral lobes with auricles reduced, not reaching over the lip base, distally round; central lip with 2, main external nerves (over its base with external, shorter branches); main central nerves thick, all main nerves connate to the basal callus. Gynostemium 3.2–3.5 mm long, elongate, erect, minutely papillate, greenish blue, staminodes and apical part of the column with anther distinctly darker coloured; front of apical portion of the column with 2 symmetrical appendages (below anther base), up to 0.35 mm long, up to 0.30 mm erect (suborbicular and gently laterally flattened); staminodia up to 1.3 mm high, 0.8–0.9 mm in diam., subequal to the anther, parallel each other, erect, slightly recurved (more at anthesis), obtriangular, upper edge cut straightly, basally disappearing just above beginning of the upper appendage line; anther narrowly ovate; rostellum subequal to the anther.
Etymology:— Names in honour of Jan Jakub Twardowski (1915–2006), a Polish poet, for his cheerfulness and admiration of nature.
Ecology:— In Castanopsis -oak mountain forests, ca. 1400 m elevation.
Distribution:— So far known only from one small population near Arau, Highlands, New Guinea.
Notes:— The type specimen comprises two plants with few-flowered inflorescences (flowers in different stages of anthesis, all flowers were studied). Due to the presence of gynostemium appendages, without any doubt this species belongs to the type section. Based on habit and lip shape, this species has similarities to P. moluccana (Smith 1900: 2) Margońska (2003b: 63.; sect. Oistochilus) but can be easily distinguished by its floral morphology, e.g., narrower petals, flat lip lamina, abbreviated pair of well-developed lip auricles and 2 suborbicular gynostemium appendages.
The newly proposed species is so far known only from one small population. However, analysing the history of many Malaxidinae species, I have found that after publication of their descriptions, although initially also based on poor specimens, these species were found at more localities. For example, P. kortylewskiana Margońska (2005: 289–291), originally based on only one collection, was recognized in two other locations in a few years.
description: Published as part of Margońska, Hanna B., 2024, A new species of Pseudoliparis (Malaxidinae, Orchidaceae) from New Guinea, pp. 297-300 in Phytotaxa 674 (3) on pages 297-299, DOI: 10.11646/phytotaxa.674.3.7, http://zenodo.org/record/14520902