Tropicos | Name - Pauridiantha insularis (Hiern) Bremek.

Looking for a taxa

Advanced research

Threatened species

Threat. pl. STP > Pauridiantha insularis

Choose Project down

English

Pauridiantha insularis (Hiern) Bremek.

Search in Muséum national d'Histoire naturelle

Search in Type Specimen Register of the U.S. National Herbarium

Search in African Plants Database at Geneva Botanical Garden

African Plants, Senckenberg Photo Gallery

Project Name Data (Last Modified On 4/14/2020)

Acceptance : Accepted

Taxon Profile (Last Modified On 10/27/2021)

Description: Shrub, 4-5 m up tall, of 1.3 m with slightly oblique spreading branches. Leaves with plastic texture, shiny dark green top with slightly sunken midrib, glaucous underside with visible dark veins (secondary leaf veins 10-17, weakly ascending). Green stipules, sparsely pubescent. Leaf domatia in primary axils only. Prophylls at the apex of the peduncle. Flowering pedicels 2-3 mm. Fruiting pedicels 4-7.5 mm. Ovary 2-locular at base (4-locular by false septa at apex) (Ntore & Lachenaud, 2019).

Habitus: Shrub up to 7 m

Phenology: Flowers buds have been observed in march; flowers in february and march; fruits in august, september, october and november.

Habitat: The species occurs sometimes aggregated, known from dense old secondary rainforest, slightly damaged; between 200 and 1,400 m altitudes.

Distribution: São Tomé (endemic)

Distribution Note: The species is endemic to São Tomé Island.

Note: Based on the 8 observations with associated DBH data (aggregated into diameter classes), the species presents a decrease of the DBH of the population which indicate no problem of regeneration in the field.

More literature: Figueiredo, E. 1997. Trees of S. Tomé and Príncipe., Ntore, S. and Lachenaud, O. 2019. Two new species and a new combination in the genus Pauridiantha Hook.f. (Rubiaceae) from tropical Africa. Adansonia 41(4): 29-40.

Case Study: São Tomé

Conservation assessment (Last Modified On 10/27/2021)

Red List Category: Vulnerable

Status of Conservation Assessment: Submitted to Red List

Date of assessment: 13 August 2021

Assessment rationale: Pauridiantha insularis is a shrub up to 5 m tall, sometimes forming aggregated subpopulations, known from old secondary dense rainforest, slightly damaged; between 200 and 1,400 m in elevation. The species is endemic to São Tomé Island and is known from 16 collections and 8 field observations. Collections were made between 1932 (Exell 415) and 2020 (Ikabanga 1110; 1137; Nguema 3331; Transects São Tomé 758) in the center of the island. Nine collections and five observations were made in the Obô National Park of São Tomé (PNOST), especially in the northeastern where seven collections were made. One herbarium specimen (Ogonovszky 337) was collected from east of Pico Ana Chaves in the center-east of PNOST. The last collection (Lachenaud 2927) is located in PNOST around Monté Carmo. The seven other collections and three observations were made outside the protected area. Three of them were made in the center-east of the island, specifically at Morro Claudino (de Oliveira 15), Macambrarà (Exell 415), and at the summit of Mongo in Monté Café area (Espirito Santo 4075). Three collections and three observations were made in the southeastern part, two collections (Lachenaud 2730; Transect São Tomé 444) and three observations at Pico Maria Fernandes and another collection (Espirito Santo 3935) at Ribeira Peixe-Cabumbé. The last collection (de Lima 86) was from Santa Clotilde in western part of the island. We consider that the occurrence corresponding to collection made in 1932 by Espirito Santo at the summit of Mongo as extirped because the habitat in this place has been severely modified. Therefore, these 15 collections and 8 observations represent 15 occurrences and at least one subpopulation. Based on a 2 x 2 km cell size, the AOO of this species is estimated as 44 km², below the upper threshold for “Endangered” status under Criterion B2. The EOO is calculated as 179.662 km², below the upper threshold for “Endangered” status under Criteria B1. The two occurrences located at Morro Claudino and Macambrarà are threatened by small-scale agricultural activities. We consider that both occurrences will disappear in a near future, and they represent one location. The occurrence located at Pico Maria Fernandes was threatened by past cacao plantations and represents one location. The occurrence at Ribeira Peixe-Cabumbé is threatened by oil palm plantation and represents one location. The occurrence at Santa Clotilde is threatened by agriculture and represents one location. Seven of the nine occurrences in the PNOST are located along the touristic road and could be threatened by tourism. Despite the occurrence at the summit of Pico São Tomé is also threatened by Cinchona invasion, these seven occurrences represent one location. The two other occurrences are not threatened and represent one location. Consequently, these 15 occurrences represent six locations (sensu IUCN, 2019), with regard to the past most important threat (small scale agriculture) which induces a degradation of the quality of habitat. Based on the disappearance of occurrence from the summit of Mongo, and the threat of the other occurrences located outside PNOST, we infer past, current, and future continuing decline in its AOO, its EOO, the number of locations, and the number of mature individuals. Moreover, we infer a past, current, and future continuing decline in the extent and the quality of its habitat. This species is thus assessed as VU B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v).

Disclaimer: This assessment was prepared on 13 August 2021. The map proposed below is only based on the specimens available on Tropicos, therefore, may not correspond to the information provided in the assessment rationale.

Conservation measures: The species should be regarded as an HCV1 (High Conservation Value), and as a consequence, it should be included in the management plan within the Obô Natural Park in which it occurs. Ex situ conservation should be tested, within São Tomé Botanical Garden of Bom Sucesso, and also internationally. Finally, a public awareness campaign must be conducted involving farmers and other private actors, NGOs, scientific institutions, and the São Tomé and Príncipe government, to ensure that the species is taken into consideration when decisions are made that could impact its conservation.