Sunday, March 5, 2017

[Botany • 2017] Garcinia hopii • A New Species (Clusiaceae) from Bidoup Nui Ba National Park, southern Vietnam


Garcinia hopii  
H.Toyama & V.S.Dang


Abstract
A new speciesGarcinia hopii H.Toyama & V.S.Dang is described from Bidoup Nui Ba National Park, southern Vietnam. This species is similar to Garcinia hendersoniana Whitmore but differs from that species in having larger leaves, clustered pistillate flowers, a greater number of sterile anthers and a larger stigma of young fruits. A description, preliminary conservation assessment, illustration, photographs and DNA barcodes of the new species are provided, as well as an updated key to Garcinia sect. Hebradendron in Indochina.

Keywords: Flora, Indochina, matK, rbcL, taxonomy


Figure 2.: Garcinia hopii H.Toyama & V.S.Dang sp. nov. A branch with leaves B abaxial surface of leaf C trunk D latex E staminate flower buds F staminate flower G pistillate flower and buds H pistillate flower J immature fruits.
A–C photographed on 22 January 2015 E photographed on 19 November 2014
D, F–I photographed on 27 February 2016, J photographed on 24 April 2015.  

Garcinia hopii H.Toyama & V.S.Dang, sp. nov.

Diagnosis: This species is similar to Garcinia hendersoniana Whitmore (endemic to Peninsular Malaysia) in elliptic-orbicular coriaceous leaves but differs from that species in relatively larger leaves (10‒23.5 × 6.5‒15.5 cm vs. 8–14 × 5.5–8.5 cm), clustered pistillate flowers (2–4 vs. solitary), a greater number of sterile anthers of pistillate flowers (40–64 vs. ca. 25) and a larger stigma of young fruits (4–6 mm vs. 3–4 mm in diam.).

Type: VIETNAM. Lam Dong Province, Bidoup Nui Ba National Park, montane evergreen forest, ...27 February 2016, H. Toyama, H. Nagamasu, S. Tagane, VS. Dang, VN. Nguyen & J. Wai V4475 [female fl. & young fr.] (holotype KYO!; isotypes DLU!, FU!, NTUF!, VNM!)

Figure 2.: Garcinia hopii H.Toyama & V.S.Dang sp. nov. A branch with leaves B abaxial surface of leaf C trunk D latex E staminate flower buds F staminate flower G pistillate flower and buds H pistillate flower I pistillate flower, some tepals removed J immature fruits. A–C photographed on 22 January 2015 E photographed on 19 November 2014 D, F–I photographed on 27 February 2016, J photographed on 24 April 2015. 



Distribution and habitat: Garcinia hopii is only known from Bidoup Nui Ba National Park, southern Vietnam. It is common in moist evergreen forests dominated by Quercus poilanei Hickel & A.Camus, Neolitsea umbrosa (Nees) Gamble, Podocarpus neriifolius D.Don, Polyosma nhatrangensis Gagnep. and Symplocos sulcata Kurz at alt. 1640–1810 m.

Phenology: Flower buds were observed in November. Flowers were observed in February and April. Immature fruits were observed in April.

Etymology: Garcinia hopii is named after Prof. Hop Tran, University of Science Ho Chi Minh City, who collected the flowering and fruiting specimens [Tran & Dang dv127 (FU, VNM)].


 Hironori Toyama, Van-Son Dang, Shuichiro Tagane, Ngoc Van Nguyen, Akiyo Naiki, Hidetoshi Nagamasu and Tetsukazu Yahara. 2017. Garcinia hopii (Clusiaceae), A New Species from Bidoup Nui Ba National Park, southern Vietnam.
 PhytoKeys. 77; 63-70. DOI:  10.3897/phytokeys.77.11575