Argyrella richardsiae: A new species of Melastome from the Miombo woodlands of Angola and Tanzania.

The Miombo woodlands are a wetland, open-forest ecosystem dominated by leguminous Miombo Trees, Brachystegia spp., which covers about 10% of the total land area of Africa. They are found at altitudes of between 1000 and 2500 m, in areas where more than 1000 mm of rain is experiences annually, with a distinct vegetation, growing on alluvial soils along river plains and in areas of extended wetlands. These woodlands are the dominant vegetation of Angola, Zambia, Tanzania, Malawi, Mozambique and Zimbabwe, and cover areas of several other Southern and Central African countries. They are home to about 75 million people, with a further 25 million urban dwellers estimated to be dependent on them for food and fuel, something which places considerable strain on this ecosystem, with areas of woodland increasingly depleted for charcoal.

In a paper published in the journal PhytoKeys on 3 July 2017, Marie Claire Veranso-Libalah of the Department of Botany and Plant Physiology at the University of Buea, and the Institut für Molekulare Physiologie and Institut für Organismische und Molekulare Evolutionsbiologie at the Johannes Gutenberg-Universität Mainz, Robert Stone of the School of Life Sciences at the University of KwaZulu-Natal, and Gudrun Kadereit, also of the Institut für Molekulare Physiologie and Institut für Organismische und Molekulare Evolutionsbiologie at the Johannes Gutenberg-Universität Mainz, describe a new species of herbaceous Melastome from the Miombo woodlands of southwestern Tanzania and central Angola.

Melastomes (Melastomataceae) are broad-leaved flowering plants found across the tropics, and occasionally elsewhere. They are related to Pomegranates, Myrtles and Evening Primroses. Melastomes can be herbs, shrubs or small trees. Some members of the group have become notorious invasive species, notably Koster's Curse (Clidemia hirta) a shrub native to Central America and the Caribbean that has become a pest species in Hawaii, Australia, Sri Lanka and parts of Africa, and the Bush Currant (Miconia calvescens) a small tree from Central and South America, which is regarded as one of the world's most invasive species, forming monospecific stands that have replaced 25% of the surviving rainforest on Tahiti.

The new species is placed in the genus Argyrella, which currently contains six species from across Sub-Saharan Africa, and given the specific name richardsiae, in honour of Mary Alice Eleanor Richards (1885-1977), a British botanist who collected plants extensively across a wide area of Africa between 1951 and 1974. It is an erect herbaceous plant, reaching about 1 m in height, branching at each node, with blade-shaped leaves and inflorescences with 5-10 pink or mauve flowers each. 

Argyrella richardsiae, (A) habit (B) glandular trichomes (C) leaf (D) flower (E) stamens: inner stamen (left), outer stamen (right) (F) seed. Doris Franke in Veranso-Libalah et al. (2017).

The species was found in Mpanda District in Tanzania and Huambo Province in Angola, and is thought likely to also be present in the southern wetlands of the Democratic Republic of Congo and Malawi and the northern part of Zambia. However, in all of these areas the Miombo woodlands are threatened by Human activities, particularly charcoal production, and for this reason Veranso-Libalah et al. consider that Argyrella richardsiae should provisionally be considered to be classified as Endangered under the terms of the International Union for the Conservation of Nature’s Red List of Threatened Species. 

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Blakea nangaritzana: A new species of Melastome from Ecuador.

The  genus Blakea comprises about 180 species of herbs, shrubs and small trees in the Melastome Familfrom Mexico, Central and South America and the islands of the Caribbean, many of which are epiphytic (live on other plants, typically in the canopy of rainforest trees).

In a paper published in the journal Phytotaxa on 9 November 2016, Diana Fernández-Fernández of the Herbario Nacional del Ecuador at the Museo Ecuatoriano de Ciencias Naturales del Instituto Nacional de Biodiversidad, Carmen Ulloa Ulloa, also of the Herbario Nacional del Ecuador at the Museo Ecuatoriano de Ciencias Naturales del Instituto Nacional de Biodiversidad and of the Missouri Botanical Garden, and Darin Penneys of the Department of Biology and Marine Biology at the University of North Carolina Wilmington, describe a new species of Blakea from the Cordillera del Cóndor mountains of southern Ecuador.

The new species is named Blakea nangaritzana, in reference to the Nangaritza River, the plants having been discovered in the watershed of this river. It is a tree reaching 25 m in height, unusual for th genus. It has leaves up to 13.5 cm in length, with a brownish silver underside, in pairs of unequal size, flowers being white and yellow and growing in bnches of up to four in the leaf axils of the upper branches, these giving rise to pitcher-shaped berries and 5-7 mm in length.

Blakea nangaritzana. Flowering branch and flower (note that anthetic flower appears 5-merous due to spider webs between two petals; 12 stamens can be counted). Juergen Homeier in Fernández-Fernández et al. (2016).

The species has been observed intermittently for about 30 years, but has not previously been formally described. The first material collected from the plant is labled as having come from an 'epiphytic shrub', however Fernández-Fernández et al. regard this as unlikely, since while other members of the genus can be flxible in habit, a large tree also living as an epiphyte seems unlikely.

Blakea nangaritzana. (A) Fruiting branch. (B) Flowering branch. (C) Young fruit with persistent bracts and cross section. (D) Lateral view of stamen. (E) Seeds. Alba Luz Arbeláez Alvarez in Fernández-Fernández et al. (2016).

All of the trees observed were found within an area of 36 square kilometers in the Conservation Area of Los Tepuyes, in a dense wet rainforest located on a snadstone plateau in the Cordillera del Cóndor in Zamora-Chinchipe Province. The plateau extends into neighbouring Peru, creating a potential extension of the habitat of about anouther 20 square kilometers. Nevertheless this is still a very small habitat, and Fernández-Fernández et al. recomend that the species be classified as Endangered under the terms of the International Union for the Conservation of Nature’s Red List of Threatened Species.

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A new species of Bush Currant from Columbia.

Bush Currants, Miconieae, are berry producing tropical trees and shrubs in the Melanastome Family, Melastomataceae. They are found throughout the tropics but at their most diverse in Colombia, where over 490 species have been described.

In a paper published in the journal Phytotaxa on 29 August 2014, Diana Gamba, Frank Almeda and Marcela Alvear of the Institute for BiodiversityScience and Sustainability at the Department of Botany at the CaliforniaAcademy of Sciences describe a new species of Bush Currant from the western cordillera in the Chocó biogeographic region of Colombia.

The new species is placed in the genus Miconia and given the specific name indicoviolacea, in reference to the violet and blue colour of its flowers. Miconia indicoviolacea is a small shrub reaching about one meter in height. It has dark green leaves and greenish stems, and produces bluish flowers and berries. The plant was only observed in January and February, when it was producing both flowers and fruit.

Miconia indicoviolacea, general habit. Marcela Alvearin Gamba et al. (2014). 

Miconia indicoviolacea has only been recorded from two sites on the western flank of the Cordillera Occidental, one in the Farallones de Cali National Park and the other within the Reserva Natural de las Aves El Pangán. These parks have a combined area of 2670.7 km³, however they are in a mountainous region and contain land with altitudes ranging from 200 to 4100 m, and Miconia indicoviolacea has been found growing only at altitudes of 600-700 m (this is quite common, many plants and animals have restricted altitude tolerances, particularly in the tropics), suggesting that the available growing range of the plant is much smaller than the area of the parks – probably only about 12 km³. As such Gamba et al. suggest that the species should be considered to be Endangered under the terms of the International Union for the Conservation of Nature’s Red List of Threatened Species.

Flowers (top) and fruit (bottom) of Miconia indicoviolacea. Marcela Alvearin Gamba et al. (2014).

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A new species of Hibiscus from Maui Island, Hawaii.

Hibiscus trees of the genus Hibiscadelphus are known only from the Hawaiian Islands, to which they are endemic. Like many Hawaiian plants and animals they have fared badly due to human activities, notably the introduction of non-native species that either out compete indigenous species or modify their environment irreversibly. Of seven previously described species of...

The origin and diversification of Mangroves.  Mangrove ecosystems, in which forests of salt tolerant trees grow between or even bellow the tide lines in tropical and subtropical waters, have been around since the Carboniferous, but modern Mangrove Forests are dominated by Angiosperms (Flowering Plants), particularly members of the Family Rhizophoraceae...

A new species of Melastome from the central Dominican Republic.                                          Melastomes (Melastomataceae) are broad-leaved flowering plants found across the tropics, and occasionally elsewhere. They are related to Pomegranates, Myrtles and Evening Primroses. Melastomes can be herbs, shrubs or small trees. Some...

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A new species of Melastome from the central Dominican Republic.

Melastomes (Melastomataceae) are broad-leaved flowering plants found across the tropics, and occasionally elsewhere. They are related to Pomegranates, Myrtles and Evening Primroses. Melastomes can be herbs, shrubs or small trees. Some members of the group have become notorious invasive species, notably Koster's Curse (Clidemia hirta) a shrub native to Central America and the Caribbean that has become a pest species in Hawaii, Australia, Sri Lanka and parts of Africa, and the Bush Currant (Miconia calvescens) a small tree from Central and South America, which is regarded as one of the world's most invasive species, forming monospecific stands that have replaced 25% of the surviving rainforest on Tahiti.

In a paper published in the journal Phytotaxa on 13 September 2013, Lukas Majure and Walter Judd, both of the Department of Biology and the Florida Museum of Natural History at the University of Florida, describe a new species of Melastome from the Cordillera Central of the Dominican Republic.

The new species is placed in the genus Miconia, and given the specific name paralimoides, meaning 'beside limoides'; the species closely resembles Miconia limoides, a species from southern Hispaniola, and is thought to be closely related to it. Miconia paralimoides is an evergreen shrub, 1-3 m in height, with hairy, oval leaves. It produces red flowers and purple berries.

Miconia paralimoides, illustation. Majure & Judd (2013).

Detail of the flower of Miconia paralimoides. Majure & Judd (2013).

Distribution of Miconia paralimoides (black circles) and Miconia limoides (open circles). Majure & Judd (2013).

See also A new species of Cherry from central Zhejiang Province, China, New species of Vochysia from Brazil and A new species of Custard Apple from the Western Ghats Mountains of India.

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