2026-07-15 イェール大学
An artist’s depiction of Likweli, a new Colobus monkey species that inhabits forest canopies in the Democratic Republic of Congo and is difficult to photograph. Illustration by Kimio Honda
＜関連情報＞
- https://news.yale.edu/2026/07/15/meet-likweli-new-monkey-species-discovered-congo-basin
- https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0349857
- https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0044271
リクウェリ：コンゴ民主共和国ロマミ国立公園で発見された、注目すべきコロブスモンキーの新種 Likweli: A remarkable new species of Colobus monkey from the Lomami National Park, Democratic Republic of Congo
John A. Hart,Junior D. Amboko,Julia L. Arenson,Emma R. Horton,Kathryn F. Coates,Jean-Pierre I. Kapale,Mardoché B. Koko,Terese B. Hart,Christopher C. Gilbert,Eric J. Sargis,Kate M. Detwiler
PLOS One Published: July 15, 2026
DOI:https://doi.org/10.1371/journal.pone.0349857
Abstract
We describe and name a new species of African monkey, Colobus congoensis sp. nov. (Primates, Cercopithecidae), from the interfluve region of the Lomami and Congo (Lualaba) Rivers in east-central Democratic Republic of Congo (DRC). Colobus congoensis is a rare and cryptic monkey, poorly known even by local communities bordering its range, some of whom use the vernacular name Likweli for the species. Between 2018 and 2022, 114 field observations were made over an estimated range of 1,700 km2. Colobus congoensis is largely restricted to high, closed canopy forest on deep clay pediments and islands of terra firme forest, where it co-occurs with two other colobine species (Piliocolobus parmentieri and Colobus angolensis). Colobus congoensis was most frequently observed in small groups (mean = 6.2 individuals), often in mixed-species associations. Mitochondrial and morphological data confirm the attribution of C. congoensis to the genus Colobus and reveal that it is the sister to Colobus satanas, from which it is geographically separated by more than 1,200 km. Comparative analysis of C. congoensis vocalizations also reveals structural similarities with C. satanas to the exclusion of other Colobus species. Among other features, C. congoensis is distinguished from C. satanas and other Colobus species by its small size, a striking orange cream patch surrounding the mouth, philtrum, and portions of the inferior nasal alae on an otherwise black face, and a white perianal patch that is covered with fine white hairs in males and is glabrous in females. We propose a preliminary IUCN Red List classification of Endangered (EN) for C. congoensis based on its small range area and population size, coupled with the projected impact of increased hunting pressure and habitat conversion. Protection of Lomami National Park, within which most of the C. congoensis range occurs, and engagement of local communities in not hunting the species are the most important actions needed to ensure the conservation of C. congoensis.
レスラ：コンゴ民主共和国固有のオナガザル属の新種と、コンゴ中央盆地の保全への影響 Lesula: A New Species of Cercopithecus Monkey Endemic to the Democratic Republic of Congo and Implications for Conservation of Congo’s Central Basin
John A. Hart,Kate M. Detwiler,Christopher C. Gilbert,Andrew S. Burrell,James L. Fuller,Maurice Emetshu,Terese B. Hart,Ashley Vosper,Eric J. Sargis,Anthony J. Tosi
PLOS One Published: September 12, 2012
DOI:https://doi.org/10.1371/journal.pone.0044271
Abstract
In June 2007, a previously undescribed monkey known locally as “lesula” was found in the forests of the middle Lomami Basin in central Democratic Republic of Congo (DRC). We describe this new species as Cercopithecus lomamiensis sp. nov., and provide data on its distribution, morphology, genetics, ecology and behavior. C. lomamiensis is restricted to the lowland rain forests of central DRC between the middle Lomami and the upper Tshuapa Rivers. Morphological and molecular data confirm that C. lomamiensis is distinct from its nearest congener, C. hamlyni, from which it is separated geographically by both the Congo (Lualaba) and the Lomami Rivers. C. lomamiensis, like C. hamlyni, is semi-terrestrial with a diet containing terrestrial herbaceous vegetation. The discovery of C. lomamiensis highlights the biogeographic significance and importance for conservation of central Congo’s interfluvial TL2 region, defined from the upper Tshuapa River through the Lomami Basin to the Congo (Lualaba) River. The TL2 region has been found to contain a high diversity of anthropoid primates including three forms, in addition to C. lomamiensis, that are endemic to the area. We recommend the common name, lesula, for this new species, as it is the vernacular name used over most of its known range.
