(CNN) — A new species of monkey has been discovered in the Democratic Republic of Congo, notable for its striking orange lips and deep, booming call.

The monkey, Colobus congolensis, known to locals as "Likoli," is the fifth new monkey species identified by scientists in Africa in the past 75 years, according to a study published Wednesday in the journal PLOS ONE.

Researchers from Florida Atlantic University and the Graduate Center of the City University of New York said in statements released Wednesday that the monkey is characterized by long, glossy black fur and striking orange and cream facial features.

The researchers added that this species has "unique skull, dental, and skeletal characteristics that distinguish it from all other known African colobus monkey species."

It is also smaller than closely related colobus monkey species, weighing about 15 pounds (6.8 kilograms).

Florida Atlantic University said: "It has sleek, light-reflecting fur and dramatic facial features accentuated by its long black hair and large, folded ears."

Image shows an illustration of Colobus congolensis. Credit: Kimio Honda

Kate Detwiler, lead author of the study and associate professor of biological sciences at Florida Atlantic University's Charles E. Schmidt College of Science, said: "The discovery of Colobus congolensis has changed our understanding of the evolution of African monkeys."

She explained: "Colobus satanas, which lives more than 1,200 kilometers away in central West Africa, is among its known relatives. But our genetic evidence shows that the two species diverged evolutionarily about 4 to 5 million years ago, one of the oldest known evolutionary splits within the colobus lineage."

The journey to document the new species began in 2008, when researchers photographed an unfamiliar monkey in the east-central part of the Democratic Republic of Congo.

Ten years later, researchers were able to observe it more clearly, recording its appearance 114 times between 2018 and 2022.

Researchers relied on studying the monkey's anatomy and observing it in its natural habitat, along with genetic analysis and local ecological knowledge, to confirm it as a new species not previously described scientifically.

Christopher Gilbert, co-author of the study and professor of anthropology at the Graduate Center of the City University of New York and Hunter College, said in a university statement: "When discovering a potentially new species, the evidence must be conclusive."

However, there are some concerns regarding the conservation of the Likoli, as observations have been concentrated within a geographic range of about 1,700 square kilometers.

The City University of New York statement said: "Researchers propose classifying Colobus congolensis as an endangered species, due to its limited range, habitat loss, and hunting pressure."

It added: "Its known habitat lies within Lomami National Park, making protection of the area critical for the species' survival."

Alexander Georgiev, a senior lecturer in primatology at Bangor University in Wales, said the analysis is "very thorough and convincing."

He told CNN on Thursday: "The discovery of a new monkey species, unknown to science and largely unknown to the people living in its habitat, is very rare and exciting."

He explained: "This explains why it took so many years for this species to be scientifically documented," noting that "the rainforests of Congo where the primates live are vast, and large parts remain poorly explored by scientists."