Prince Bernhard's titi monkey

The species is known to locals of the regions it inhabits as a zog-zog or zogue-zogue;[5] however, that name has also been applied to the coppery titi monkey (Plecturocebus cupreus).[6] Its English common name was selected in honor of Prince Bernhard of the Netherlands, who created the Order of the Golden Ark, an award equivalent to knighthood, presented each year to a group of conservationists.[5]

Prince Bernhard's titi monkey belongs to the genus Plecturocebus. It was originally described by Marc van Roosmalen et al. in 2002 as Callicebus bernhardi, with the holotype being a complete, mature skeleton, collected in November 1998.[5] It and Callicebus stephennashi were the 37th and 38th species of primates to be described since 1990,[7] and the 23rd and 24th monkeys described since that year.[8] Van Roosmalen explained how the area where it is found is filled with undescribed species.[7] In 2016, the genus was split into four new genera, with bernhardi ending up in the moloch group of the newly created genus Plecturocebus. Other members of that group include P. moloch, P. cinerascens, P. hoffmannsi, P. baptista, and P. brunneus.[9]

Illustration of various titi monkeys; the furthest toward the upper right is this species

C. bernhardi has dark orange sideburns, underparts, and inner limbs (of a more uniform shade than P. cinerascens). The upper regions of its body and head are grayish black, while on its back, these shades are mixed with brownish agouti or reddish brown. Its face is black, with white hairs around its nose and mouth. Its ears are also black, with whitish tufts. Its mostly black tail is contrasted by a white tip. Its hairs are 5 centimetres (2.0 in) long. Its grayish forehead and crown help distinguish it from P. brunneus, which is dark brown to black in these areas, while the white ear tufts and tail tip distinguish it from P. hoffmannsil and P. baptista. Its lack of black vibrissae (whiskers) sets it apart from P. dubius.[5]

The Prince Bernhard's titi monkey is of least-concern by the International Union for Conservation of Nature (IUCN). The organization considered it to not be at risk due to its large range and lack of human impact on its habitat. They concluded that it has a stable population and no known threats.[1] However, later research efforts found that its habitat, in the Arc of Deforestation (an area in the southeastern Amazon rainforest defined by heavy deforestation), was at risk. It is estimated that it will lose 44.5 percent of its current range over the course of the next 24 years (three generations for this species). From this study, the researchers concluded that its status should be changed to vulnerable.[12]