Thismia nigricoronata: A new species of Parasitic Plant from Laos.

Thismias (Thismiaceae) are a small group of Parasitic Plants found throughout the tropics, with a few temperate species known from North America, Japan, New Zealand and Australia. They parasitize the Mycorrhizal Fungi with which all vascular plants have a relationship, but where other plants exchange sugars produced by photosynthesis for nutrients obtained from the soil by the Fungi, Thismias do not photosynthesise, instead taking both nutrients and sugars from the Fungi and giving nothing in return. In order to do this Thismias must target Fungi in relationships with other Plants (since Fungi do not produce sugars), preventing the Thismia from growing to any great size. Thismias are related to Bat Flowers and Arrowroots; they were formerly classified within the (also parasitic) Burmanniaceae, but it is now recognised that while the two groups are fairly closely related, both are more closely related to some non-parasitic plants than they are to each-other.

In a paper published in the journal Phytotaxa on 5 September 2017, Pankaj Kumar, Stephen Gale and Ji-Hong Li of the Flora Conservation Department at Kadoorie Farm and Botanic Garden, Somsanith Bouamanivong of the Biotechnology and Ecology Institute of the Lao Ministry of Science and Technology, and Gunter Fischer, also of the Flora Conservation Department at Kadoorie Farm and Botanic Garden, describe a new species of Thismia from Laos.

The new species is named Thismia nigricoronata, where 'nigricoronata' means 'black-crowned'. The species reaches 5.5 cm in height, and is crowned by a dark structure formed from three fused perianth lobes. The species was found on a limestone slope at an altitude of 544 m, in Vang Vieng District of Vientiane Province in Laos. Only ten plants were found, though they were hard to detect and might therefore be more widespread, though Kumar et al. note that the area where the plants were found is a forest without protection, in immediate danger of clearance.

Thismia nigricoronata. (A) Plant in habitat. (B) Habit. (C) Close-up of the crown. (D) Whole plant showing the structure of the crown. (E) Whole plant showing the structure of the annulus. (F) Transverse section of the perianth tube. Kumar et al. (2017).

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Three new species of Ginger from Laos.

The Ginger Family, Zingiberaceae, appears to have a biodiversity hotspot in the Indochina region (Cambodia, Laos and Vietnam), though this has been little studied, with the last comprehensive review published in 1908. Numerous new species have been described in the past decade nsuggesting that the group is in need of more detailed study in this area.

In a paper published in the journal Blumea on 10 October 2014, Jana Leong-Škorničková of The Herbarium of the Singapore Botanic Gardens, Otakar Šída of the Department of Botany at the National Museum in Prague, Somsanith Bouamanivong of the Biotechnology and Ecology Institute of the Ministry of Science and Technology of Laos and Keooudone Souvannakhoummane and Kithisak Phathavong of the Pha Tad Ke Botanical Garden describe three new species of Zingiberaceae from Laos, two of which are placed in the Turmeric genus Curcuma and one of which is placed in the Ginger genus Zingiber.

The first new Turmeric species is named Curcuma corniculata, meaning ‘having small horns’ in reference to the shape of the flowers. This is a herbaceous plant reaching a meter in height, producing 5-9 leaves up to 47 cm in length from a pseudostem made up of the sheaths of the leaf stems (petioles). Flowers are produced in bracts from the base of this stem, and are red and orange in colour. The flowers last only a single day, and are produced from the end of May till July, which is the start of the rainy season. The plants were found growing on a single limestone outcrop 866 m above sea-level in Louangphrabang Province.

Curcuma corniculata, (a) whole plant, and (b) inflorescence. Leong-Škorničková et al. (2014).

The second new species of Turmeric is named Curcuma flammea, meaning ‘flaming’ in reference to the fiery red colour of the flowers. This is a herbaceous plant reaching 70 cm in height, producing 1-5 leaves up to 36 cm in length from a pseudostem that can reach 30 cm. Flowers are a fiery red and orange colour and last only a single day, being produced from the end of May till July, which is the start of the rainy season. The species is known only from a single location, on a limestone slope in a dense Diptocarp forest in Vientiane Province, Laos.

Whole plant of Curcuma flammea. Leong-Škorničková et al. (2014).

The new Ginger species is named Zingiber jiewhoei, in honour of Tan Jiew Hoe of the Singapore Gardening Society for his support on Ginger research at the Singapore Botanic Gardens and of taxonomy in Laos. This is a herbaceous plant producing arching leafy shoots up to 2.5 m in length. Flowers are 7-9 cm long, deep red in colour, and produced from the base of the plant, these are produced in the early rainy season, and open overnight, from about 3 pm to early the following morning. The plant was found growing at a single location, near a stream in a lowland deciduous forest in Vientiane Province, Laos.

Zingiber jiewhoei (a) whole plant including roots, (b) growing leaves. Leong-Škorničková et al. (2014).

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A new species of Turmeric from the Bù Gia Mập National Park in southern Vietnam.

Turmeric (Curcuma) plants are members of the Ginger Family (Zingiberaceae) native to India, southern China, Southeast Asia, Indonesia, Papua New Guinea and northern Australia. Several species are grown for use as a spice or dye, and the more colourful species are popular garden plants in tropical areas, though they need constant warm temperatures and high rainfall to thrive. The plants can reproduce both sexually by flowering and asexually by means...

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