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

Japanese morning glory (Ipomoea nil)

Japanese morning glory ( Ipomoea nil ) is a species of plant in the Convolvulaceae family, a climber with twining stems that grow up to 5 meters long. The green, finely hairy leaves are 14 cm long, heart-shaped at the base, entire or 3-5-lobed, tapering at the edges. The flowers are funnel-shaped, blue to reddish-purple with a whitish tube, 5 cm wide and up to 7 cm long. TAXON Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Solanales Family: Convolvulaceae Subfamily: Convolvuloideae Tribe: Ipomoeeae Genus: Ipomoea L. in Sp. Pl.: 159 (1753) Species: Ipomoea nil (L.) Roth in Catal. Bot. 1: 36 (1797) HOMOTYPIC SYNONYMS Convolvuloides triloba Moench in Methodus: 452 (1794) Convolvulus nil L. in Sp. Pl., ed. 2.: 219 (1762) Pharbitis nil (L.) Choisy in Mém. Soc. Phys. Genève 6: 439 (1833 publ. 1834) HETEROTYPIC SYNONYMS Convolvulus caeruleus (Roxb. ex Ker-Gawl.) Spreng. in Syst. Veg., ed. 16. 1: 593 (1824) Convolvulus coelestis G.Forst. in Fl. Ins...

Moist pimpernel (Lindernia dubia)

Moist pimpernel ( Lindernia dubia ) is a species of plant in the Linderniaceae. It is a herbaceous, ground-growing, erect, cylindrical stem with red to light brown color. The leaves are green, oval, up to 10 mm long, up to 7 mm wide, with rounded tips and reddish veins. The flowers are funnel-shaped, bluish-white, with yellow veins. TAXON Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Lamiales Family: Linderniaceae Genus: Lindernia All. in Auct. Syn. Meth. Stirp. Hort. Regii Taur. 3: 178 (1766) Species: Lindernia dubia (L.) Pennell in Monogr. Acad. Nat. Sci. Philadelphia 1: 141 (1935) Variety: Lindernia dubia var. dubia, Lindernia dubia var. rhizomatosa Pennell ex D.Q.Lewis HOMOTYPIC SYNONYMS Ilysanthes dubia (L.) Barnhart in Bull. Torrey Bot. Club 26: 376 (1899) Ilysanthes gratioloides Benth. in A.P.de Candolle, Prodr. 10: 419 (1846) Gratiola dubia L. in Sp. Pl.: 17 (1753) Limnophila dubia (L.) M.R.Almeida in Fl. Maharashtra 3B: 393 (2001)...

Heart of Jesus (Caladium bicolor)

Keladi merah or heart of Jesus or angel wings ( Caladium bicolor ) is a species of flowering plants in Araceae, large leaves and arrow-shaped with various patterns of green, white and red, has many cultivars, often used as an ornamental plant and has been cultivated since the 18th century. C. bicolor grows in open areas in the forest and on river banks and becomes inactive during the dry season, 40-90 cm tall, reproduces itself by dividing tubers, requires high humidity but is not inundated and requires large tree shade. This plant has one to five leaves, oval-shaped or broad heart or slender arrows with a length of 15-45 cm, the leaf bone is centered at a point at the base of the stalk and spreads out, the surface is smooth and the edges are flat, flexible and has layers waterproof wax. The leaves have many hues depending on the cultivar, generally green on the edges with red in the middle and along the leaf bone with white patches on the entire surface. A long, green or bla...

Dlium