Nyctocalos tunjuharii Berhaman, 2023

Nyctocalos tunjuharii Berhaman View in CoL , sp. nov. — Fig. 1 View Fig

This species is morphologically most similar to N. cuspidatus (Blume) Miq. but differs by its linear calyx teeth of ≥ 3 mm long, its corolla tube of <10 mm long and included stamens that reach less than half the length of the upper dilated part of the corolla tube. — Type: Berhaman, Leopold & Sulaiman SAN 134785 About SAN (holo SAN; iso K, L), Malaysia, Sabah, Tenom, Kallang , N5°9'32" E115°55'40", 21 Oct. 1993 GoogleMaps .

Etymology. I have named this species in honour of Tun (Dr.) Juhar Bin Datuk Hj. Mahirudin, the present Sabah Governor and Chancellor of Uni- versiti Malaysia Sabah, who loves plants and gardening, and is also very

supportive of conservation work in Sabah. It is hoped that his support will bring conservation efforts to a greater level.

Liana, without tendrils, stems to 1.5 cm thick, climbing by twining. Leaves trifoliolate, subcoriaceous to coriaceous; petiole 4.5–5.5 cm long; terminal leaflet with petiolule 4–4.5 cm long, blade broad-ovate to elliptic, 13.5–15 by 7–7.5 cm, base slightly rounded, apex acute, lateral veins 6–8 pairs, tertiary veins re- ticulate, with many dark dot-glands scattered on lower surface, mostly just below the apex; lateral leaflets with petiolules 1.2– 1.4 cm long, blade ovate to elliptic, 11.5–13.4 by 5.8–6.2 cm, base slightly rounded, apex acute, lateral veins 5–7 pairs, tertiary veins reticulate, with many dark dot-glands scattered on the lower surface mostly just below the apex. Inflorescence a raceme, terminal to short axillary shoots bearing 2–3 leaf pairs, c. 16 cm long; rachis c. 4 mm thick, bearing 32 flowers. Flowers on short pedicels 5–6 mm long; calyx cup c. 5 by 4 mm, glabrous; lobes 5, teeth-like, linear, 3–4 by c. 0.5 mm, with tiny round glands at their base; corolla short-infundibular, white, glabrous on both surfaces, c. 8.2 cm long (excluding lobes), basal tubular part c. 4 cm long and 0.4–0.5 cm wide, upper dilated part c. 4.2 by 2.6 cm; corolla lobes 5, broadly obovate, c. 17 by 21 mm, papillate on both surfaces, recurved in the open flower, with tiny round glands on the outer surface on the median part of the corolla lobes and just below, as well as a few just below the region between adjacent lobes; stamens 5, filaments c. 1.8 cm long, inserted at the base of the upper dilated part of the corolla tubes, sparsely hairy at the very base (insertion), anthers yellow, glabrous, widely divergent, c. 6 by 1 mm, included within the corolla tube and reaching less than half the length of the upper dilated part, appendage 1–1.5 mm long; disk a slight swelling around the base of the ovary; ovary subcylindric to subellipsoid, 2–3 by c. 1 mm wide, style filiform, 2.7–3 cm long, slightly exserted from the corolla mouth, gla- brous, stigma glabrous, 1.5–2 by c. 1 mm, lobes 2, spreading just before the flower opens. Fruit pods not known. Seeds not known.

Distribution — So far, the new species N. tunjuharii , is known from a few collections from the type locality in the Tenom district of Sabah (N5°9'32" E115°55'40"). Recent collections from nearby Mantailang, not far from Kallang Waterfall, have increased the number of collections.

Habitat & Ecology — Lower montane forest on ultramafic soil, at 300–500 m above sea level. The liana was growing on trees or climbing on rock surfaces along a small stream, light 60–80 % below and in the canopy.

Conservation status — There is no detailed information on the population size of N. tunjuharii at the type locality or at the new locality in Mantailang. The latter site is in a gazetted Forest Reserve , affording the species a level of protection because the reserve is inside the Sabah Parks system. Material from a recent, March 2022, collection from the type locality is now being cultivated at the nursery of the Faculty of Tropical Forestry , Universiti Malaysia Sabah for ex situ conservation. So, the conservation status of this newly recognised species has not been formally evaluated. Accordingly, IUCN criteria ( IUCN 2019) suggest that it should be listed as ‘ Not Evaluated’ ( NE) .

Additional specimens (Paratypes): Berhaman & Maycock AB 1568 ( K, L, SAN), Malaysia, Sabah, Tenom, Kallang , 24 Oct.2017 ; Berhaman & Godoong AB 1618 ( K, L, SAN), Malaysia, Sabah, Tenom, Mantailang Forest Reserve , 13 Nov. 2018 .

Note — The new species has trifoliolate leaves but is well distinguished from the other described species of this group by its corolla and calyx characters. It has an infundibuliform corolla and so is different from N. brunfelsiiflorus (which has a salverform corolla), confirming that it belongs to the same group as the other two species ( N. shanicus and N. cuspidatus ). Its corolla tube is much longer, c. 8 cm, than that of N. shanicus (corolla tube 4.8–6.2 cm long), but much shorter than that of N. cuspidatus (13.3–20.5 cm long). In contrast to the stamens of N. cuspidatus , which protrude slightly from the corolla mouth, the stamens of the new species are well included within the corolla tube and reach only less than half the length of the upper dilated part ( Fig. 1b View Fig ). Furthermore, the long linear calyx lobes of this new species distinguish it from all the other species, in which the calyx lobes are short-triangular.