The Marañón Valley

A national treasure of Peru’s biodiversity with global significance.

RBGE’s Tropical Diversity team is working on a project in Peru, to document plant diversity and discover new species in the incredible Marañón valley.

The Río Marañón is a major tributary of the Amazon River, the upper reaches of the river run through a dry inter-Andean valley in northern Peru.

The valley is renowned for its high number of restricted endemic species. Previous work has shown that the seasonally dry tropical forests found in the valley are particularly rich in endemic species and that much of the valley remains under-collected by scientists. In addition, the forests in the valley have a key role in maintaining water provision and soil stabilisation benefiting human populations in the Andes and ensuring the health of the Amazon River downstream. However, the forests in the Marañón valley are under severe anthropogenic pressure due to their accessibility and fertile soils, and are in need of protection.

During the Newton funded project, Increasing knowledge of dry and montane ecosystems across Peru, RBGE and our Peruvian partners will be producing the first checklist of seed plants for the dry forests of the upper Marañón watershed. This project will involve collecting new specimens, cataloguing specimens already present in local herbaria, and helping our local partners get this specimen data online for use by the wider scientific community.

The RBGE Tropical Diversity team has a long history of working in the dry forests of Peru, and is continuing to develop projects with our Peruvian partners.
Marañón Project
- Increase botanical knowledge.
- Collect new botanical specimens.
- Create a checklist of the Marañón dry forests.
- Collect seed for ex-situ conservation.
A new publication by the team:

Las plantas comunes del bosque seco del Marañón
Biodiversidad para las comunidades locales

Paúl Gonzáles, Asunción Cano, Tiina Särkinen, Zoë Goodwin, Niels Valencia, Inés Sachahuamán y José Luis Marcelo-Peña

Gallery -

A steep dry slope with large boulders covered in spiny shrubs and large candelabra like cacti.

A branch with large oval, opposite leaves and clusters of many tiny small green flowers.

A muddy brown river winding through a steep valley with sparse spiny shrubs on steep slopes.

Small open red flowers with four red petals.

A muddy brown river in a steep rocky valley with slopes covered in green shrubs.

A red and yellow flower with long yellow stamens.

A narrow bridge over muddy brown river winding through a steep valley with dry mountains in the background.

A cluster of fluffy white flowers on a branch with green leaves.

A green shrub with fluffy white flowers growing out of a rocky crevice in cliff.

Low, dry forest with cacti and spiny, swollen trunked trees on a steep rocky slope.

Green leaves, small yellow seeds and dry brown bean pods displayed on a black cloth background.

An upright inflorescence with open yellow flowers and some green flower buds.

Two men standing under a small, spindly tree in a dry flat valley bottom, with steep rocky slopes and blue sky in the background.

Brown winged seeds on the end of a branch.

Cacti and spiny shrubs with blue flowers, steep rocky slopes covered in low cloud in the background.

A small complex flower with five white petals and a series of yellow and red structures at the centre, against a background of green leaves.

Low, dry forest with cacti and spiny trees on a steep rocky slope.

Project Team

Zoë Goodwin - Lead project co-ordinator & botanist (RBGE, UK)

Paúl Gonzáles - Lead project co-ordinator & botanist (USM, Peru)

Tiina Särkinen - Primary Investigator (RBGE, UK)

Asunción Alipio Cano Echevarría - Primary Investigator (USM, Peru)

Niels Marciano Valencia Chacón - (USM, Peru)

Sebastián Riva Regalado - Fieldwork driver & technical help (USM, Peru)

Elluz Raquel Huaman Melo - (USM, Peru)

Pamela Jessica Nina Falcón - Digitization (USM, Peru)

Ancel Brisett Nuñes Marroquín - Digitization (USM, Peru)

Richard Junior Balvin Bernal - Digitization (USM, Peru)

Marlene Miñano Rivera - Finance (USM, Peru)

Carlos Augusto Reynel Rodriguez - Botanist (MOL, Peru)

Aniceto Daza Yomona - Fieldwork & Botanist (MOL, Peru)

Jose Luis Marcelo Peña - Botanist (La Universidad Nacional de Jaén, Peru)

Sonia Palacios Ramos - Finance (MOL, Peru)

Sandy Knapp - Botanist (BM, UK)

Project Objectives

Increase botanical data for montane regions by digitising, scanning, and curating specimens: Most of the herbarium work will take place at USM where we will aim to digitise, scan and curate as many specimens as we can during the project, and get specimens named by taxonomic experts.
Collect new specimens in the upper reaches of the Marañón valley where little biodiversity data exists thus far: Our collecting will focus on the Marañón dry forests which are home to many endemic species and genera. Field work will take place between January-May 2020. Collecting areas include (1) San Vicente de Paul (Distrito Longotea, La Libertad), (2) Huamachuco (Distrito Aricapampa, Ancash), (3) Sihuas (Distrito Sihuas, Ancash), and (4) Chagas (Distrito Chingas, Ancash).
Build a checklist of vascular plants of the Marañón dry forests.
Collect seed in collaboration with local partners for nurseries to grow Marañón endemics for regeneration projects linked to mining & dam projects.

Project Partners

Universidad Nacional Mayor de San Marcos (USM)

Universidad Nacional Agraria La Molina (MOL)

FONDECYT

CONCYTEC

Project Funding

This project, Increasing knowledge of dry and montane ecosystems across Peru, has been funded by the Newton Fund (project number 418235692) through the British Council in conjunction with assistance of the British Embassy in Lima.

Endemic plants of the Marañón Valley

Apocynaceae
Allamanda weberbaueri Markgr.

Begoniaceae
Begonia joshii Moonlight*

Boraginaceae
Cordia iguaguana Melch. ex I.M.Johnst.

Cactaceae

Armatocereus rauhii Backeb.
Browningia altissima (F.Ritter) Buxb.
Calymmanthium substerile F. Ritter
Praecereus euchlorus (F.A.C.Weber) N.P.Taylor subsp. jaenensis (Rauh & Backeb.) Ostolaza
Rauhocereus riosaniensis Backeb. subsp. jaenensis (Backeb.) Ostolaza

Clusiaceae
Clusia rigida M.H.G. Gust.

Euphorbiaceae
Ditaxis katharinae Pax

Leguminosae
Arquita celendiniana (G.P.Lewis & C.E.Hughes) Gagnon, G.P.Lewis & C.E.Hughes
Calliandra mollissima (Humb. & Bonpl. ex Willd.) Benth.
Cenostigma pluviosum (DC.) Gagnon & G.P.Lewis var. maraniona (G.P.Lewis & C.E.Hughes) Gagnon & G.P.Lewis
Coursetia cajamarcana Lavin
Maraniona lavinii C.E.Hughes, G.P.Lewis, Daza & Reynel
Mimosa incarum Barneby
Mimosa jaenensis Särkinen, Marcelo-Peña & C.E.Hughes
Mimosa lamolina C.E.Hughes & G.P.Lewis
Mimosa pectinatipinna Burkart
Parkinsonia peruviana C.E.Hughes, Daza & Hawkins

Malpighiaceae
Heteropterys tiinae W.R.Anderson

Polygonaceae
Ruprechtia albida Pendry

Rutaceae
Esenbeckia cornuta Engl.

This list of seed plants endemic to the dry forests of the Marañón valley is currently incomplete. If you have any suggestions for further additions please contact Zoë Goodwin.

*New species published as part of this project.

Further Reading