Litsea honbaensis de Kok, 2023

De Kok, Rogier P. J., 2023, The Lauraceae Juss. of Indo-China: fifteen new species, four new combinations and two neotypifications, Adansonia (3) 45 (1), pp. 1-25 : 13-15

9. Litsea honbaensis de Kok , sp. nov.

( Figs 7 ; 9 )

DIAGNOSIS. — This species differs from its close relative Litsea helferi Hook. f. by having a glabrous petiole which is slightly swollen (while L helferi has a sparsely hairy slender petiole); fruits which are 14- 16 × 7-8 mm on a cupule about 5.4 mm diameter (while L. helferi has fruits 28-32 × 18-24 mm and a cupule 6.5-6.9 mm diameter).

TYPE SPECIMEN. — Vietnam, Khanh Hoa: 12 km to Hon Ba, 12°6’56.016”N, 108°58’40.008”E, 24.VI.2004, Soejarto 13305 (holo-, P[P01052426]).

DISTRIBUTION. — Vietnam ( Fig. 7 ).

ECOLOGY. — Growing in forests over granite between 800-900 m altitude. Flowering from January to May; fruiting in February.

CONSERVATION ASSESSMENT. — Endangered (EN B1ab(i,iii), B2ab(ii,iii)). This species is only known from eight collections representing five localities in Vietnam (plus one locality that could not be found). An analysis of the Extent of Occurrence (EOO) and Area of Occupancy (AOO) gives an IUCN Conservation Assessment of Endangered.

ADDITIONAL COLLECTIONS SEEN. — Vietnam. Nghe-An (Vinh): Huyên de Nghia-Dam , 11°51’3.6”N, 108°36’25.2”E, 18.V.1941, Poilane 30571 ( P [ P06856488 ]) . — Lào Cai: Chapa et Cho-Bo, Chapa , 22°20’3.984”N, 103°50’51”E, VII.1930, Pételot 5365 ( P [ P02003173 , P02003180 ]) ; Chapa et Cho-Bo, 800 m, 6.IX.1926,20° 49’0.012”N, 105°12’E, Poilane 13165 ( P [ P01976054 , P01155417 ]) . — Thua Thien-Hue: Nui Back Ma station ,près de Hu ế, 16°10’0.984”N, 107°49’58.008”E, 24.IV.1939, Poilane 29982 ( P01976319 ) . — Lâm Đ ồng: Blao , 11°28’40.8”N, 107°44’16.8”E, 28.VI.1933, Poilane 22776 ( P02011236 ) . — Tuyên Quang, Tonkin, Nguyen Luang , 21°46’36.228”N, 105°13’40.872”E, VI.1925, Pételot 1931 ( P02011174 ) .

DESCRIPTION

Tree 8-10 m tall; dbh c. 20 cm. Twigs slender, 1-1.6 mm thick, rounded in cross-section, densely hairy when young, glabrescent; hairs yellowish, appressed; terminal leaf bud lanceolate, c. 2.5 mm long, apex acute, velutinous. Leaves alternate; blade elliptic to lanceolate, 3.3-6.5 × 1-3 cm, apex acuminate, base cuneate, membranous, secondary nerves 4-5 pairs, curving near margin, tertiary nerves reticulate; upper surface glabrous, midrib and secondary nerves sunken, tertiary nerves indistinct; lower surface glaucous, glabrous, midrib and secondary nerves raised, tertiary nerves distinct; petiole half-terete, 8-14 mm long, glabrous, slightly swollen.

Inflorescences in axils of leaves, 7.5-10 mm long, in clusters of umbels, densely hairy. Flowers white; male flowers: perianth lobes linear, 1-1.4 × 0.5-0.6 mm, apex rounded, inside glabrous, outside velutinous; stamens 1-1.5 mm long; female flowers: perianth lobes linear, 1-1.5 × 0.5-0.6 mm, apex rounded, inside glabrous, outside velutinous; ovary c. 0.9 mm diameter, glabrous.

Fruits 1-3 per infructescence, ellipsoid, 14-16 × 7-8 mm, apex acute, smooth, glabrous; cupule shallow, c. 5.4 × 2.3 mm, margin entire, patent, smooth, sparsely hairy; stalk swollen up to 1.9 mm thick, slightly hairy (see Fig. 9 ).

Figures

FIG. 7. — Distribution of Cinnamomum petelotii Kosterm.ex de Kok,sp.nov.(), Cinnamomum scalarinervium Kosterm.ex de Kok,sp.nov.(), Litsea banaensis de Kok,sp. nov. (), Litsea honbaensis de Kok, sp. nov.() and Litsea nhatrangensis de Kok, sp. nov. ().

FIG. 9. — Plate of Litsea honbaensis de Kok, sp. nov.: A, twig with leaves, inflorescence and infructescence; B, infructescence with fruit; C, detail of leaf under surface. All from Poilane 13165 (P01155417). Drawing by Giulia Iaconelli. Scale bars: A, 5 cm; B, 1.5 cm; C, 0.5 cm.