Sunday, September 8, 2019

[Botany • 2019] Gluta laosensis (Anacardiaceae) • A New Species from Vientiane, Laos


Gluta laosensis Tagane & Kameda

in Tagane, Kameda, Phouphasouk & Souladeth, 2019. 
ນ້ຳກ້ຽງນ້ອຍ  ||  DOI: 10.11646/phytotaxa.415.3.6 

Abstract

A new species of Gluta (Anacardiaceae), Gluta laosensis Tagane & Kameda, from Vientiane, Central Laos, is described and illustrated. A new species is easily distinguished from the other species of the genus in Indo-China in having short petioles less than 4 mm long, obovate-oblong or oblong-elliptic leaf blade with rounded to slightly cordate base, and 18–24 pairs of secondary veins.

Keywords: flora, Indochina, Sapindales, taxonomy, Eudicots

FIGURE 1. Gluta laosensis Tagane & Kameda.
A) Flowering twigs, B) Section of twigs showing reddish-brown exudate, C) Portion of abaxial leaf surface, D) Sapling with young leaves, E) Inflorescence, F) Flower, top view, G) Flowers, side view, H) Flower some petals and calyx removed, I) Fruits. Photos A & E taken on 20 Feb. 2014, B & I on 1 June 2016, C, F–H on 25 Feb 2018, D on 19 Apr. 2014.



Gluta laosensis Tagane & Kameda, sp. nov. (Fig 1.)

 TYPE:—LAOS. Vientiane Capital: Sangthong District, Napo Village, 220 m elev., ..., 25 Feb. 2018, Kameda K164 [fl.] (holotype FOF!; isotype P). 

Similar to Gluta velutina Blume in leaf shape, short petiole to 4 mm long (to 7 mm in G. velutina) and fruits without winglike petals but differs in lower leaf more or less covered with brown hairs (vs. glabrous in G. velutina), pubescent petals (vs. glabrous), and smooth reniform-fruits (vs. pale brown scurfy and subglobose, with irregularly tuberculate ridges at base). 
...

Distribution:—LAOS. Vientiane Capital (so far known only from Sangthong District).

 Habitat and Ecology:— In mixed deciduous forest, disturbed semi-evergreen forest on hills, characterized by a typical monsoon climate with a distinct rainy (May to November) and dry season (December to April); 200–310 m elevation. Flowering specimens were collected in February and fruiting specimens in June. 

Etymology:—The specific epithet refers to the country in which this species is found. 
Vernacular name:—ນ້ຳກ້ຽງນ້ອຍ (Nam kiang noy). 

Note:— Gluta laosensis is easily distinguished from the other species of the genus in Indo-China in having short petioles less than 4 mm long, obovate-oblong or oblong-elliptic leaf shape, rounded to slightly cordate leaf base, and 18–24 pairs of secondary veins. Gluta velutina distributed in Indonesia (Java, Kalimantan, Sumatra), Malaysia (Borneo, Peninsular), Myanmar, Thailand (Peninsula) and Vietnam is apparently similar in leaf shape, but in addition to the diagnosis mentioned above, they differ in their habitats: G. laosensis grows in mixed deciduous forest and secondary semi-evergreen forest, while G. velutina grows at edge of tidal rivers (Kochummen 1996, Chayamarit 2010).


Shuichiro Tagane, Chika Kameda, Souphachay Phouphasouk and Phetlasy Souladeth. 2019. Gluta laosensis (Anacardiaceae), A New Species from Vientiane, Laos. Phytotaxa. 415(3); 153–156.  DOI: 10.11646/phytotaxa.415.3.6