Hoya gauttierensis Rodda & Simonsson, 2022

Hoya gauttierensis Rodda & Simonsson View in CoL , sp. nov. — Fig. 4 View Fig

Similar to Hoya leucantha in flower shape (corolla rotate, star-shaped), but distinguished by leaf shape (elliptic in H. gauttierensis , lanceolate in H. leucantha ), corolla size and corolla lobe shape (corolla 45–50 mm diam with narrowly triangular lobes in H. gauttierensis ; 12–15 mm diam with deltate lobes in H. leucantha ), and corona shape (stipitate, conical in H. gauttierensis ; not stipitate, with a central conical part surrounded by spreading lobes in H. leucantha ). — Type: K. Gjellerup 890 (holo L [ L.2726492]; iso BO [ BO0110492 ]), Indonesia, Papua Province, Gauttier Mountains , c. 350 m, 7 Nov. 1911 .

Etymology. Hoya gauttierensis is named after the type locality in the

Gauttier Mountains (now Pegunungan Gauttier).

Climber, likely epiphytic, latex colour unknown. Stems cylindrical, slender, 1.5–2 mm diam, pubescent to glabrescent, internodes 7–15 cm long. Roots not observed. Leaves: petiole terete, 1.2–2 by 1.5–2 mm, pubescent; lamina elliptic, coriaceous when dry, 5–12 by 3.5–5 cm, glabrous above, very sparsely pubescent underneath, apex cuspidate, base cuneate, rounded to very shallowly cordate; venation pinnate, secondary veins 7–12 each side. Basal colleters one at each lamina base, conical, c. 0.7 mm long. Inflorescence one per node, tropism unknown, likely positive, pseudo-umbelliform, consisting of 2 – 6 flowers; peduncle extra-axillary, terete, 4.5–9 cm by c. 1 mm, older peduncles forming a rachis from previous flowerings, pubescent; pedicels filiform, 15–20 by c. 0.5 mm, glabrous. Calyx lobes reflexed at anthesis, ovate to oblong, 2–3 by 1.5–2 mm, apex acute, glabrous, sparsely ciliate. Basal colleters numerous, scattered along the base of calyx lobes, ovate, c. 0.25 mm long. Bud shape unknown. Flower colour unknown. Corolla rotate, star-shaped, 45–50 mm diam when flattened; tube ± conical, c. 7 mm long, outside glabrous, inside pubescent; lobes narrowly triangular, 15–18 by 7–9 mm, apex acuminate, outside glabrous, inside pubescent. Corona staminal, conical, c. 4.5 mm high, c. 6 mm diam, with a stipe c. 1.5 mm tall, pubescent; lobes oblong, c. 4.5 by 1 mm, inner process erect, bifid, outer processes rounded, with basal revolute margins. Pollinia oblong, c. 430 by 180 µm, without pellucid margin; corpusculum globose, c. 320 by 220 µm; caudicles attached to the lower half of the corpusculum, S-shaped, c. 150 µm long. Ovary oblong, c. 2 mm long, glabrous. Fruit and seed not observed.

Distribution — The species is only known from the type locality in Gauttier Mountains, Papua Province, Indonesia.

Habitat & Ecology — Based on the information included with the type specimen, this species was found ‘in forest, on riverbank’.

Conservation status — Data Deficient ( DD; IUCN 2012 ). Hoya gauttierensis is known only from the type specimen collected 111 years ago .

Notes — This species has relatively large corollas with long narrow lobes, and a tall conical corona with oblong lobes, which sets it apart from most species from New Guinea. As mentioned in the diagnosis it is most similar to H. leucantha , but easily distinguished in leaf shape and size, corolla size, and corona type .

Additionally, the stipitate conical corona of H. gauttierensis is similar to that of H. koteka Simonsson & Rodda , which is also endemic to New Guinea. However, H. koteka is likely a shrub with single-flowered inflorescences and 7–10 by 2.5–3 mm, narrowly lanceolate corolla lobes, while H. gauttierensis is a climber with 2–6 flowered inflorescences and 15–18 by 7–9 mm, narrowly triangular corolla lobes.