Thomas, 1908
Callicebus hoffmannsi
Type locality: Urucurituba, Santarem.
Description: A greyish species with light yellowish underside and hoary hands and feet.
General colour of body above about as in C. donacophilus, greyish brown with a subdued undertone of rufous, most marked on the lions. Crown grizzled grey, nearly as in C. egeria. Cheeks, whole of the under surface, and inner side of limbs light yellowish or pale buffy, very different from the strong rufous of these parts in allied species. Arms and legs grizzled grey like the crown, without brown or rufous suffusion. Hands and feet blackish grizzled with white, the results being a hoary-slate grey. Tail black throughout, the hairs scarcely paler at their bases. Anterior nares large, widely open, evenly rounded.
Measurements: Head and body 375mm; tail 440mm; hind foot 91mm
Skull: greatest length 65; nasal opening 7.8x6.8; premolar-molar series 15
Type: old male BritishMuseum no. 8.5.9.11
This species is widely different from any hitherto described, as its hoary slaty-grey hands and feet are quite unlike the red, black or whitish feet found in other species. C. cinerascens of Spix would appear to have similar feet, but its under surface is also grey, and not yellowish. The tail of C. hoffmannsi also is even more completely black than that of C. remulus, most of the allied species of this genus having this member either reddish or whitish. Nor has any previously known species of the genus a similarly coloured under surface.
Elliot, 1913
Callicebus hoffmannsi
Synonyms: Callicebus hoffmannsi (Thomas, 1903).
Type locality: Urucurituba, Santarem, Lower Amazon, Brazil (BritishMuseum).
Description: Tail long, under parts very light colour.
Top of head, hands and feet black, the hairs with white tips which give the dominant hue, making these parts appear as if frosted; upper parts of body dark rufous, the hairs being black and ringed and tipped with rufous; upper side of arms with the hairs black, tipped with white; outer side of legs hoary, paler than arms; cheeks and under parts, and inner side of arms and legs, all but cheeks very sparsely haired, yellowish white; tail black with a brownish gloss.
Measurements: Total length, 815mm; tail, 440mm; foot, 91mm.
Skull: occipito-nasal length, 68 ; Hensel, 42 ; zygomatic width, 43 ; palatal length, 27; median length of nasals, 17; length of upper molar series, 16.3.
Remarks: While resembling C. donacophilus from Bolivia somewhat on the upper parts of the body, this species is easily recognized by its black tail and hoary head, black hands and feet, and pale under parts. The specimen is old with teeth much worn.
Lönnberg, 1939
Callicebus hoffmannsi
Locality: The Stockholm museum has 1 specimen originating from West of the Rio Tapajoz, Irocanga; 1 specimen from West of Rio Tapajoz, Patinga and 1 specimen from Rio Arapiuns (West of Rio Tapajoz), Casa Nova.
Description: These specimens agree completely with the description by Thomas, but at the same time it must be admitted that they display a general pattern that agrees closely with that of C. remulus, the colours are, however, in most cases paler and agree with the designations made by Thomas. The “cheeks, whole of under surface, and inner side of limbs” are, as he says “light yellowish or pale buffy”. The hands and feet form an exception from the general paleness, as also described by Thomas, being according to him “blackish, grizzled with white, the result being a hoary slate-grey”. The darkness of these parts together with the paleness of the rest of the animals constitutes the differences between this titi monkey and the one named C. remulus which has as a rule paler feet. It may be added that the more or less greyish white tuft at the extreme of the tail in C. remulus is lacking in C. hoffmannsi. It is thus no difficulty to distinguish the two forms from each other, that I am inclined to consider C. hoffmannsi from the western side of the Rio Tapajoz as a geographical subspecies of C. remulus i.e. C. moloch on the eastern side of the same river. It is therefore hardly probably that the type of C. hoffmannsi has been collected at Santarem on the eastern side of the river.
Collectors’ measurements: Males: total length 790/716mm; tail 440/415mm;
Hind foot 99/95mm.
Female: total length 805mm; tail 460mm; hind foot 100mm.
Skull: measurements of 3 individuals in publication.
Cruz Lima, 1945
Callicebus hoffmannsi
Synonym: Callicebus hoffmannsi (Thomas, 1908).
Description: Top of the head, including the forehead, black speckled with slightly yellowish white, the black hairs with brownish roots and white tips; hairs on the shoulders and outer surface of the forelimbs similar but longer. Hairs on the flanks and on the outer surface of the hind limbs brownish, ringed or only tipped with slightly greyish white. Hairs on nape, back and upper side of the base of the tail brownish at base with the apical section ringed with black and tawny. Hand and feet black, the hairs white tipped. Sides of the hairs being whitish at base; under parts and inner side of limbs light ochraceous yellow, the hairs with whitish roots. Tail except on the upper surface of the base black. Under parts and inner side of limbs of a juvenile female specimen belonging to the Museu Goeldi collection and acquired at Parintins, Amazonas, much paler ochraceous than on the adult male of the same collection which was used for the description above. 
Measurements: (in the flesh), head and body 310mm; tail 430mm; foot 87mm.
Remarks: Type in the BritishMuseum (Natural History)
This form is related to the group consisting of C. donacophilus, C. ornatus, C. moloch, C. remulus and C. emiliae (the first two extra-Amazonian), with which it has many points in common but from it is distinguished principally by the colouring of the hands, feet and tail.
The acquisitions of the Museu Goeldi and of the StockholmMuseum enlarge our knowledge of the distribution of this monkey. Besides Urucurituba, whence came the type, it has been obtained at Vila Braga, on the left bank of the Tapajoz, where it was found in the woods; at Santa Julia, on the border between the States of Pará and Amazonas; and at Parintins, where it must be noted only one specimen was acquired from a third party. As, however, this is not a city where there is a regular trade in animals, as at Santarem for instance, it is probable that the animal was captured in the vicinity. The specimens of the Scandinavian museum are also from the left bank of the Tapajoz (Patinga; Iroçanga; Casa Nova, ArapuinsRiver).
Vieira, 1955
Callicebus hoffmannsi
Synonyms: Callicebus hoffmannsi (Thomas, 1908).
Distribution:Para (Patinga; Murua; Iricanga; Itaituba; Taperinha; Bom Jardim).
Cabrera, 1958
Callicebus moloch hoffmannsi
Synonyms: Callithrix moloch (Meerwarth, 1903); Callicebus hoffmannsi (Thomas, 1908).
Distribution: Amazonian Brazil, west of the TapajosRiver.
Remarks: When indicating the type locality, Thomas made one of the inaccuracies that are so frequent when European authors refer to the South-American geography: “Urucurituba, Santarem”, the village is 350 km west of Santarem, on the other side of the Tapajon and in a different state, which resulted in the opinion of Lönnberg (1939) on the geographical separation between this subspecies and the real moloch.
Hill, 1960
Callicebus moloch hoffmannsi
Type locality: Urucurituba, Rio Tapajoz, Pará, Brazil. Type in British Museum.
Distribution: Left bank of Rio Tapajoz (Urucurituba, Vila Braga, Santa Julia, Patinga, Iroçanga, Casa Nova and Rio Arapiuns).
Description: Chiefly distinguished by colour of extremities and tail, which are black without white tip to tail (cf. emiliae), and by the light ochraceous-yellow under parts, contrasted with the darker dorsal areas than in moloch.
Crown, including forehead, black speckled lightly with yellowish-white tips; shoulders and outer aspects of fore-limbs similar, but hairs longer; nape, median part of back and upper surface of base of tail with similarly coloured hairs, but on flanks and lateral aspects of hind-limbs the hairs longer still, brownish and ringed or only tipped with greyish-white; hands and feet black with hairs white tipped; sides of head and throat light ochraceous-yellow, forming a collar, the hairs whitish basally; under parts and medial surfaces of thighs similar.
According to the note by collector on label of type male, a female in the Pará Museum is quite like the type, but hands and feet are not so dark and under parts are a little richer yellow. A juvenile female from Parintins, according to Lima, with under parts paler than in adult.
Measurements: head and body 310/375; tail 430/440; foot 87/91.
Skull: see measurements in publication.
Hershkovitz, 1963
Callicebus moloch hoffmannsi
Synonyms: Callicebus hoffmannsi (Thomas, 1908); Callicebus baptista (Lönnberg, 1939); Callicebus moloch baptista (Cabrera, 1958).
Type locality: Urucurituba, Rio Tapajóz, Pará, Brazil. The type locality was originally given as “Urucurituba, Santarem”. Santarem, in this case, refers to the region of the lower Rio Tapajóz, and not to the town itself which is on the right bank of the mouth of the Tapajóz and in the type region of Callicebus moloch moloch. Urucurituba at 3º 30’S, on the left bank of the Tapajóz is in the area whence all recorded titis agree with the original description of C. m. hoffmannsi. Two other places with the name Urucurituba also lie within the range of hoffmannsi. One is located on the right side of the Amazon (58º W) just north of Lago do Baptista, the other on the right bank of the Madeira (3º 35’S) just south of Lago do Baptista. It is assumed that the titis from these localities, both in the state of Amazonas, would more nearly resemble the type of baptista than the type of hoffmannsi. Type in British Museum.
Distribution: South of the Rio Amazonas, Brazil, from the left bank of the Rio Tapajoz in Pará to the right bank of the Rio Madeira in Amazonas.
Description: (key to species:) general body colour grey, reddish or brown; under parts like back or sharply defined reddish orange or buff; hind feet black, brown, red or grey, tail grey or blackish with tip grey or grey mixed with black; throat like chest; forearms grey, red, dark brown sometimes blackish above; upper surface of hands grey to blackish never sharply contrasted with colour of upper side of wrists.
Forehead like crown, grey to reddish brown and not defined from nape; outer sides of forearms coarsely ticked greyish, buffy or brown. Sides of head bright yellow or orange sharply contrasting with grizzled crown; upper portion of pinna like crown; tail dominantly blackish at least basally. Upper surface of hands and feet dominantly blackish.
Measurements: see table in publication.
Remarks: specimens representing hoffmannsi from the left bank of the Tapajóz are notably darker on upper and outer sides of trunk and limbs and appreciably paler on under parts and sides of face than typical moloch from the opposite of the Tapajóz. Topotypes at hand of baptista from the right side of the lower Rio Madeira are as dark on upper and outer surfaces of body and limbs and tail as topotypical hoffmannsi. Their under parts and cheeks, however, are more saturate than those of either hoffmannsi or moloch and quite or nearly as deeply red as those from cupreus from the opposite side of the Madeira and higher up the Solimoes. That the two named forms may represent local colour varieties is indicated by 4 specimens from Villa Braga, Rio Tapajóz, examined by Thomas. The under parts of two were “pale yellowish like the type (of hoffmannsi) while the other two have under parts strong ochraceous buffy”. Inasmuch as there is no physical barrier between the titis of the left bank of the Tapajóz and those of the right bank of the Madeira, I follow Cabrera (1958) in treating baptista as a synonym of hoffmannsi.
Intergradation between hoffmannsi and cupreus, its nearest geographic ally on the west, is through brunneus at the headwaters of the Rio Madeira.
Specimens examined:
Brazil – Amazonas: Lago de Baptista; Pará: Arará.
Hershkovitz, 1988
Callicebus hoffmannsi
Remarks: Equivocal locality records on the east bank of the Rio Tapajos suggest enclave populations of C. hoffmannsi where C. moloch occurs.
Hershkovitz, 1990
Callicebus hoffmannsi hoffmannsi
Synonym: Callicebus hoffmannsi (Thomas, 1908).
Type Locality: Urucurituba, Rio Tapajos, Para, Brazil. The type locality was originally given as "Urucurituba, Santarem." Santarem, on the right bank of the lower Rio Tapajos, is type locality of Callicebus remulus (= C. moloch). Urucurituba at 3°30'S on the opposite bank of the Rio Tapajos is in the area whence nearly all titis examined agree with the holotype of hoffmannsi. Nevertheless, other east (right) bank Rio Tapajos specimens (Fordlandia, 2) are either mislabelled or had been transferred in an oxbow cut-off from west to east bank. Although west bank hoffmannsi and east bank moloch are specifically distinct (Hershkovitz, 1988), specimens of the first may be enclaves within the range of the second rather than true sympatriots. Holotype in British Museum.
Distribution: Central Brazil south of the Rio Amazonas, from left bank Rio Tapajos-Juruena in the states of Para and Amazonas, west to right bank Rio Canuma-Sucundure in Amazonas.
Description: Upper and outer surface of head, trunk, and limbs greyish to blackish agouti; forehead like crown, whitish ear tufts absent; sideburns, under parts of body, and inner side of limbs sharply contrasted pale orange or yellowish; tail dominantly blackish agouti to nearly entirely blackish, tail tip sometimes entirely buffy.
Measurements: See publication.
Comparisons: Distinguished from Callicebus moloch by blackish agouti upper surface of cheiridia, by blackish tail usually without contrastingly pale pencil, and pale orange or yellowish under parts, inner side of limbs, and sideburns; from C. hoffmannsi baptista mainly by pale orange or yellowish, not bright reddish or mahogany, under parts and sideburns; from all other species with which comparisons need be made by agouti forehead undifferentiated from crown, agouti outer side of arms, legs, and upper side of cheiridia contrasted with pale orange or yellowish sideburns and under parts.
Specimens Examined: Total 61, all in Brazil.
Para: Arapiuns, Rio; Arara; Arua; Brasilia Legal, Rio Tapajos; Casa Nova; Fordlandia; Igarape Amorim; Igarape Bravo; Irocanga; Itaituba; Patinga; Santa Rosa, Ilha Urucurituba; Sumauma, Rio; Urucurituba (holotype); Vila Bella, Boca Andira; Vila Bella Imperatriz; Vila Braga, Rio Tapajos.
Kobayashi, 1995
Based on cranial measurements, the genus can be divided in two major clusters, which can be further divided into several clusters:
Cluster 1: with the donacophilus cluster (including modestus, olallae, d. donacophilus and d. pallescens), the cupreus cluster (including caligatus, c. cupreus, c. discolor and c. ornatus) and the moloch cluster (including brunneus, h. hoffmannsi, h. baptista, moloch and cinerascens).
Cluster 2: with the personatus cluster (including p. personatus, p. nigrifrons, p. melanochir, dubius and t. purinus) and the torquatus cluster (including t. lucifer, t. lugens, t. medemi, t. regulus and t. torquatus).
The phylogenetic position of C. modestus is morphometrically debatable, since it was clustered with the donacophilus group by the analysis of the Q-mode correlation coefficients, but its plots on the principal component analysis was isolated away from those of any other forms. Although Hershkovitz (1988, 1990) pointed out the elongated skull's unusual appearance and regarded it as the most primitive species in the genus, considerable doubt exist that it might be an anomalous mutant, since only one adult specimen is known. If the curious character of its cranial morphology is in fact stable, C. modestus might be assignable an independent group as indicated by HERSHKOVITZ (1988, 1990). In order to clarify its true status, sufficient numbers of samples need to be collected.
Groves, 2001
Callicebus hoffmannsi
Synonym: Callicebus hoffmannsi (Thomas, 1908).
Distribution: South of the Rio Amazon, from Rio Tapajos-Jurena to Rio Canuma.
Description: Body medium to dark brown; hairs very short, light grey-brown base, three pairs of alternating very pale tawny and black bands, and tip tawny. Crown grey, the hairs with a white base, black shaft, white tip. Limbs as body, or a bit greyer, becoming greyer towards hands and feet. Tail black, with tendency to have a light tip. Underside orange-red, this tone broadly extending to inner aspects of limbs (including hands and feet).
Remarks: I expected that when I was able to examine skins for myself, I would reduce all three (moloch, baptista and hoffmannsi) to subspecies under C. moloch; instead, study of the specimens in AMNH demonstrated to me that each is specifically distinct.
Roosmalen et al., 2002
Callicebus hoffmannsi
Type locality: Urucurituba, Rio Tapajós, state of Pará, Brazil. The holotype is an adult male, skin and skull, British Museum of Natural History no. 1908.5.9.11, collected by W. Hoffmanns in February 1906.
Distribution: Central Amazonia, Brazil, south of the Rio Amazonas in the states of Amazonas and Pará, from right bank of Rio Canumã, where it is parapatric with C. cinerascens, to left bank Rio Tapajós, where it is parapatric with C. moloch, south to the north (right) bank of Rio Sucundurí, where it is parapatric with an as yet undescribed species of titi, and north along the south bank of the Paraná do Urariá and Paraná do Ramos, east along the left bank of the Rio Andirá and the right bank of the Rio Uíra-Curupá south of the town of Parintins where it is parapatric with C. baptista (in the lower Rios Andirá/Uirá-Curupá interfluve and north of the Paraná do Urariá and Paraná do Ramos).
Description: Basically a two-coloured (greyish and yellowish-white) titi. Upper and outer surface of head, trunk, and limbs greyish agouti, sometimes light grey to almost white; forehead greyish as crown, with or without a black or blackish coronal band not as far as the greyish ears; lacking white ear tufts; sideburns, under parts of body, inner side of limbs sharply contrasted yellowish to white; mid-dorsum olivaceous-greyish; tail blackish agouti to black; no whitish cheiridia nor tail-tip. Distinguished from C. moloch by upper surface of hands and feet blackish agouti and black tail; from C. baptista by pale yellowish, not bright reddish or mahogany, sideburns and under parts, and black tail; from C. cinerascens by chest, belly, and inner side of limbs uniformly buffy (yellowish-white); from C. bernhardi by lacking white ear tufts, white cheiridia and white tip of the tail and having yellowish-white instead of bright orange sideburns, beard, under parts of body, and inner side of limbs.
Dumas et al., 2005
Callicebus hoffmannsi
2n=50 (data in table).
Barlow and Peres, 2006
Callicebus hoffmannsi
Locality: hydrological catchment of the Rio Maró, a 3rd order, clear-water tributary of the Amazon River. Fieldwork was carried out on both banks of the river, both within and outside the recently created Tapajós-Arapiuns Extractive Reserve of westernmost Pará, central Brazilian Amazonia (2°44’S, 55°41’W).
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