Skip to main content

Mount Ayanganna bonnetia (Bonnetia ayangannensis) from the Pantepui of western Guyana, South America

Mount Ayanganna bonnetia (Bonnetia ayangannensis) from the Pantepui of western Guyana, South America

NEWS - Researchers describe Mount Ayanganna bonnetia (Bonnetia ayangannensis) from the summit of Mount Ayanganna tepui in Guyana, in terms of morphology, distribution, micromorphological characterization under scanning electron microscopy, leaf venation and comparison with closely related species.

Bonnetia Mart. is the most representative genus of the woody flora of Pantepui and one of the groups with the greatest endemism in the local flora. The genus has 32 species currently known in tropical America. This study adds Bonnetia ayangannensis and the number of endemics in Pantepui to 27 species.

Micromorphological analysis of the leaves shows serrated margins, sometimes with deciduous spinular protrusions. The abaxial leaf surface is rough and has numerous sessile glands and stomata. At higher magnification, the surface appears warty-crusty with granular protrusions.

The margins of the bracts have short-stalked glands with thin-walled elongated heads. The petals have short-stalked glands on the outer surface and short-stalked glands on the margins. Seeds have longitudinal stripes.

B. ayangannensis closely resembles B. paniculata, but differs in leaf blades (1-)1.5-4 cm (vs. 6-18 cm), leaves with glandular punctuations on abaxial surface (vs. glands absent), bracts 2-3 mm (vs. 6-7 mm), sepals ciliated and glandular (vs. ciliated and glands absent) and 2-4 × 1-2 mm (vs. 10 mm × 6-7 mm).

B. ayangannensis differs from B. tepuiensis and B. rubicunda by having leaves that are wedge-shaped at the base (vs. rounded in B. tepuiensis), stalked flowers (vs. sessile), arranged in inflorescences (vs. solitary flowers), pinnate venation, flowers with sepals and petals less than 8 mm long (vs. parallel venation, sepals and petals more than 18 mm long in B. rubicunda).

The epithet refers to Mount Ayanganna, where the new species was discovered and is known only from two collections collected at close range from a single population on the eastern summit slope. It occurs in scrub forest on sandstone, together with B. tepuiensis, Clusia spp. and Brocchinia spp. at elevations of 1900-2000 meters.

The researchers recommend B. ayangannensis be placed in the Critically Endangered category. The species is primarily known from two locations separated by only about 0.06 km over an area of 4 km2. However, considering that at 1900 meters the actual area is thought to be much smaller. In addition, anthropogenic climate change is a serious threat to habitats in the highlands.

Original research

Barbosa-Silva RG, Torke BM, Viana PL (2024). A new species of Bonnetia Mart. (Bonnetiaceae) from the Pantepui of South America. PhytoKeys 247: 55-65, DOI:10.3897/phytokeys.247.126950

Dlium theDlium

Popular Posts

Mossman mahogany (Goniocheton arborescens)

Mossman mahogany ( Goniocheton arborescens ) is a species of plant in the Meliaceae, a small to large tree, up to 20-30 meters tall, flowering and fruiting when only 1 meter high, the trunk has a diameter of up to 45 cm, the bark is gray-brown, smooth or with light cracks. The leaves are opposite, 5 pairs or 10 pieces and petioles 0.5-1 cm long. The leaves are up to 18 cm long, up to 9 cm wide, a main vein in the middle with many small pinnate veins, a pointed tip, dark green upper side, lighter and glabrous underside. The inflorescence is an axillary thyrse measuring up to 8 cm covered with small yellow-brown hairs. Flowers about 10 mm long, creamy green to white, usually 5 petals 10 mm long and 2.2 mm wide. Stamen tubes arise from the base of the petals, 10 anthers 1 mm long at the distal end. The capsule fruit is round and slightly flat, up to 3 cm in diameter, bald, bright red and contains 5 seeds. Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida...

Gunung Sewu Geopark

Gunung Sewu Geopark or Gunung Sewu UNESCO Global Geopark or Pegunungan Sewu (Thousand mountains) are elongated mountains in Kulonprogo Regency, Bantul Regency and Gunung Kidul Regency in Yogyakarta Province, Wonogiri Regency in Central Java Province, to Tulungagung Regency in East Java Province on Java Island, Indonesia. The uniqueness of the ecosystem encourages the International Union of Speleology to propose the Sewu Mountains Karst Area into one of the world's natural heritages in 1993. On September 19 2015, UNESCO announced Gunung Sewu as the Global Geopark Network. Sewu Mountain is rich in biodiversity, archeology, history and cultural aspects. The Pacitan rock culture represents Paleolithic to Neolithic artifacts in Southeast Asia. About 1,802 square kilometers of the area contain traces of prehistoric settlements. Some prehistoric people lived in caves, while others lived in open spaces. Characteristics Gunung Sewu is a classic tropical karst landscape and is domin...

Barong Temple

Candi Barong or Barong Temple is a Hindu site in on the Baturagung hills in the Kewu Plain in Candisari Village, Bokoharjo Sub-district, Prambanan District, Sleman Regency, Yogyakarta Province, Indonesia where decoration in the temple niches looks like a 'Barong' face. This temple is also called Sari Suragedug Temple as mentioned in the Ratu Baka (Queen Baka) Inscriptions (856 AD) and Pereng Inscriptions (863 AD). The Queen Baka inscription tells of a king named Sri Kumbaja or Sri Kalasodbhava building three 'lingga' is Krttiwasalingga with Dewi Sri, Triyarbakalingga with Dewi Suralaksmi and Haralingga with Dewi Mahalaksmi. The Pereng inscription said in 784 Saka (860 AD) that Rakai Walaing Pu Kumbhayoni conferred rice fields and two hills at Tamwahurang for the maintenance of the Syiwa sacred building called Bhadraloka. The experts argue that Sri Kumbaja or Sri Kalasodbhava is Pu Kumbhayani and the Shiva building in question is the Barong Temple. Unlike the oth...