|Distribution of Jentink's duiker|
Jentink's duiker (Cephalophus jentinki), also known as gidi-gidi in Krio and kaikulowulei in Mende, is a forest-dwelling duiker found in the southern parts of Liberia, southwestern Côte d'Ivoire, and scattered enclaves in Sierra Leone. It is named in honor of Fredericus Anna Jentink.
Jentink's duikers stand around 80 cm (31 in) tall at the shoulder and weigh about 70 kg (150 lb), making them the largest species of the duikers. They are gray from the shoulders back and dark black from the shoulders forward.  A white band goes over the shoulders, between the two colours and joining the white undersides. Jentink's duikers have long, thin horns, which curl back a little at the ends, and reach between 14 and 21 cm (5.5 and 8.3 in).
Jentink's duikers live mainly in very thick rainforest, where they eat fruit, flowers, and leaves which have fallen from the canopy, as well as stems of seedlings, roots, and, to the annoyance of local farmers, palm nuts, mangos, and cocoa pods. They are nocturnal and shelter during the day in dense thickets, or buttress roots, apparently in pairs. Jentink's duikers are reported to be territorial animals, and when frightened, will run very quickly, but wear themselves out easily.
The species was first recognized as a new species in 1884, though it was not described until 1892.  The species then vanished until a skull was found in Liberia in 1948. Sightings have occurred in its habitat since the 1960s. In 1971, the species was successfully bred in the Gladys Porter Zoo. 
Recent population numbers are not available. In 1999 it was estimated that around 3,500 Jentink's duikers remained in the wild, but the following year others suggested less than 2,000 were likely to remain.  They are threatened primarily by habitat destruction and commercial bushmeat hunters. 
|Phylogenetic relationships of Jentink's duiker (Johnston et.al. 2012)|
It is classified under the genus Cephalophus and the family Bovidae. It was first described by British zoologist Oldfield Thomas in 1892 in the Proceedings of the Zoological Society of London .  The generic name probably comes from the combination of the New Latin word cephal, meaning head, and the Greek word lophos, meaning crest.  The word "duiker" comes from the Afrikaans word duik, or Dutch dūken - both mean "diver". 
A 2001 phylogenetic study divided Cephalophus into three distinct lineages: the giant duikers, east African red duikers and west African red duikers. Jentink's duiker was classified as a giant duiker along with the yellow-backed duiker (C. silvicultor), Abbott's duiker (C. spadix), and the bay duiker (C. dorsalis).  In 2012, Anne R. Johnston (of the University of Orleans) and colleagues constructed a cladogram of the subfamily Cephalophinae (duiker) based on mitochondrial analysis. They showed that within the "giant duiker" group, Jentink's duiker formed a clade with the bay duiker, and the zebra duiker is sister to this clade. Similarly, Abbott's duiker and yellow-backed duiker form a clade sister to Sylvicapra . Jentink's duiker and the bay duiker probably evolved during the Pleistocene, less than 2.5 million years ago. 
The term antelope is used to refer to many species of even-toed ruminant that are indigenous to various regions in Africa and Eurasia.
A duiker is a small to medium-sized brown antelope native to sub-Saharan Africa, found in heavily wooded areas. The 22 extant species, including three sometimes considered to be subspecies of the other species, form the subfamily Cephalophinae or the tribe Cephalophini.
The Abbott's duiker, also known as minde in Swahili, is a large, forest-dwelling duiker found only in a few scattered enclaves in Tanzania. It may be a subspecies of the yellow-backed duiker. It is very rare, and the first photograph of an Abbott's duiker in the wild was taken as recently as 2003.
The bay duiker, also known as the black-striped duiker and the black-backed duiker, is a forest-dwelling duiker native to western and southern Africa. It was first described by British zoologist John Edward Gray in 1846. Two subspecies are identified. The bay duiker is reddish-brown and has a moderate size. Both sexes reach 44–49 cm (17–19 in) at the shoulder. The sexes do not vary considerably in their weights, either; the typical weight range for this duiker is 18–23 kg (40–51 lb). Both sexes have a pair of spiky horns, measuring 5–8 cm (2.0–3.1 in). A notable feature of this duiker is the well-pronounced solid stripe of black extending from the back of the head to the tail.
The black duiker, also known as tuba in Dyula, is a forest-dwelling duiker found in the southern parts of Sierra Leone, Liberia, Côte d'Ivoire, Ghana, Benin, and Nigeria.
The blue duiker is a small antelope found in central, southern and eastern Africa. It is the smallest duiker. The species was first described by Swedish naturalist Carl Peter Thunberg in 1789. 12 subspecies are identified. The blue duiker reaches 32–41 centimetres (13–16 in) at the shoulder and weighs 3.5–9 kilograms (7.7–19.8 lb). Sexually dimorphic, the females are slightly larger than the males. The dark tail measures slightly above 10 centimetres (3.9 in). It has short, spiky horns, around 5 centimetres (2.0 in) long and hidden in hair tufts. The subspecies show a great degree of variation in their colouration. The blue duiker bears a significant resemblance to Maxwell's duiker.
The black-fronted duiker is a small antelope found in central and west-central Africa.
The Maxwell's duiker is a small antelope found in western Africa.
Ogilby's duiker is a small antelope found in Sierra Leone, Liberia, Ghana, southeastern Nigeria, Bioko Island and possibly Gabon. No subspecies are recognized.
The Ruwenzori duiker or Ruwenzori red duiker is a stocky but small antelope found only in the Ruwenzori Mountains between Uganda and, probably, the Democratic Republic of Congo. They may be a subspecies of the black-fronted duiker or the red-flanked duiker.
Weyns's duiker is a tiny antelope found in the Democratic Republic of Congo, Uganda and western Kenya. It is sometimes spelled "Weyn's", "Weyns", or "Weyns'" duiker.
The zebra duiker is a small antelope found primarily in Liberia, as well as the Ivory Coast, Sierra Leone, and occasionally Guinea. They are sometimes referred to as the banded duiker or striped-back duiker. It is believed to be one of the earliest duiker species to have evolved.
The yellow-backed duiker is a forest dwelling antelope in the order Artiodactyla from the family Bovidae. Yellow-backed duikers are the most widely distributed of all duikers. They are found mainly in Central and Western Africa, ranging from Senegal to Western Uganda with possibly a few in Gambia. Their range also extends southward into Rwanda, Burundi, Zaire, and most of Zambia.
The red forest duiker, Natal duiker, or Natal red duiker is a small antelope found in central to southern Africa. It is one of 22 extant species form the subfamily Cephalophinae. While the red forest duiker is very similar to the common duiker, it is smaller in size and has a distinguishing reddish coloring. Additionally, the red forest duiker favors a denser bush habitat than the common duiker. The Natal red duiker is more diurnal and less secretive than most forest duikers, so therefore it is easier for them to be observed. In 1999, red forest duikers had an estimated wild population of 42,000 individuals.
Cephalophus is a mammal genus which contains at least fifteen species of duiker, a type of small antelope.
The white-legged duiker is a medium-sized antelope species from the subfamily of duikers (Cephalophinae) within the family of bovids (Bovidae). It is native to Gabon and the Republic of the Congo. It was described as subspecies of the Ogilby's duiker by Peter Grubb in 1978. After a revision of the ungulates in 2011 by Colin Groves, it is now regarded as distinct species.