On the Dental Formulae of Brazilian Terrestrial Carnivora (Mammalia)

Abstract

Key compendia of Neotropical mammals contain conflicting information regarding the dental formulae of Brazilian carnivores. The objective of the present study was to review the dental formulae of Brazilian Canidae, Felidae, Mephitidae, Mustelidae and Procyonidae. We illustrate the dental morphology of all Brazilian genera, and report intra and interspecific tooth variation, and supernumerary teeth. We examined skulls and mandibles of 710 Brazilian terrestrial carnivores, including juvenile and adult specimens. Adults of all genera have three incisors and one canine in each quadrant. Members of the canid family have the following postcanine formula P 4/4 and M 2/3, except Speothos venaticus (M 1/2); felids have P 3/2 and M 1/1; mephitids present P 2/3 and M 1/2; mustelids show P 2-4/2-3 and M 1/2; and finally, procyonids have P 4/4 and M 2/2, except Potos flavus (P 3/3). Supernumerary teeth were found in individuals of seven genera in every family except Procyonidae. Although our results corroborate previous descriptions based on vouchered material, we detected several incongruences being replicated, possibly due to the lack of examination of museum vouchers, propagating erroneous information without critical analysis. Finally, we present a dichotomous key based on the review of dental morphology.

Key words
Canines; carnassial tooth; incisors; molars and premolars

INTRODUCTION

Teeth play a crucial role in mammalian evolution (Bergqvist 2003, Hillson 2005, Ungar 2010) and are important for the classification, diagnosis, and identification of mammalian taxa, in particular carnivores (e. g.: Cope 1879, Savage 1976, Van Valkenburgh 1991). In fact, the order Carnivora is defined, among other characters, by the loss of the third upper molar (Wesley-Hunt & Flynn 2005) and by the presence of enlarged shearing postcanines, the carnassials, considered a key diagnostic trait for the order (Ungar 2010). Likewise, the loss of the third lower molar is a diagnostic character for the suborder Feliformia (Wesley-Hunt & Flynn 2005). Members of the order typically have three small incisors, one large canine, and a variable number of pointed premolars and molars with high cusps (Hillson 2005, Ungar 2010).

Researchers have investigated the dentition of Neotropical Carnivora since the early studies of New World mammal fauna (Winge 1895, Paula-Couto 1950, 1979). Currently, several books about Neotropical and Brazilian mammals describe the dental formulae of Carnivora species and are used as primary source for research (e.g.: Reis et al. 2010, Eisenberg 1989, Emmons & Feer 1997, Eisenberg & Redford 1999). While performing a revision of this information in the literature, we detected several inconsistencies among these sources as well as factual errors for a few of the taxa in these publications.

The aim of this contribution is, therefore, to present a description of the dental loci of Brazilian terrestrial carnivores, based on the examination of an extensive series of vouchered specimens. We report the dental formulae for all genera of Brazilian carnivores, document cases of intra and interspecific variation and supernumerary tooth, and present the replacement order of deciduous teeth in several taxa. We illustrate the general dental morphology of all genera, and provide discussion about tooth identity and general trends as well as a dichotomous key based on dental morphology.

MATERIALS AND METHODS

We analyzed 710 specimens housed at the mammal collection of the Museu Nacional/UFRJ, Rio de Janeiro, Brazil. We examined only specimens with both skull and mandible: in the case of specimens with missing teeth, the alveoli were used to determine the total number of teeth (Novacek 1986). We included all terrestrial carnivore genera with families represented in Brazil, namely Felidae, Canidae, Mephitidae, Mustelidae, and Procyonidae. We examined all Brazilian species within these genera and defined as juvenile those individuals with deciduous teeth present, and adults as those individuals with full permanent dentition. Taxonomic nomenclature follows Paglia et al. (2012); see Table I for included taxa and sample size, and appendix 1 for a list of all examined specimens.

Table I
List of Carnivora taxa examined, with sample size and dental formula. Taxa marked with an asterisk (*) denote intraspecific variation in dental formula.

Family	Species	Sample size	Dental formula
Canidae	Atelocynus microtis	1	I 3/3, C 1/1, P 4/4, M 2/3
	Cerdocyon thous*	153
	Chrysocyon brachyurus	25
	Lycalopex gymnocercus	1
	Lycalopex vetulus	20
	Lycalopex sp.	1	I 3/3, C 1/1, P 4/4, M 3/3
	Speothos venaticus*	5	I 3/3, C 1/1, P 4/4, M 1/2
Felidae	Leopardus braccatus*	3	I 3/3, C 1/1, P 2-3/2, M 1/1
	Leopardus pardalis*	36	I 3/3, C 1/1, P 3/2, M 1/1
	Leopardus tigrinus*	28
	Leopardus weidii	12
	Panthera onca*	26
	Puma concolor	22
	Puma yagouaroundi	20
Mephitidae	Conepatus semistriatus*	6	I 3/3, C 1/1, P 2/3, M 1/2
	Conepatus chinga	1
Mustelidae	Eira barbara	33	I 3/3, C 1/1, P 3/3, M 1/2
	Galictis vittata*	5
	Galictis cuja	43
	Lontra longicaudis*	14	I 3/3, C 1/1, P 4/3, M 1/2
	Pteronura brasiliensis	8
	Mustela africana*	4	I 3/3, C 1/1, P 2-3/2, M 1/2
Procyonidae	Bassaricyon alleni	3	I 3/3, C 1/1, P 4/4, M 2/2
	Nasua nasua	138
	Procyon cancrivorus	43
	Potos flavus	59	I 3/3, C 1/1/, P 3/3, M 2/2

Dental nomenclature follows Owen (1840-45) and Luckett (1993). These authors defined incisors as those teeth which are placed at the pre-maxillary bone and the corresponding occluding teeth of the lower jaw; the canines as the first tooth on the maxillary bone and its counterpart at the lower jaw, which occlude in front of the upper canine; the premolars are the remaining teeth which are replaced; while the molars are those postcanine that are not replaced. The dental formula is presented in quadrants as traditionally depicted in mammalogy textbooks: I x/x, C x/x, P x/x, M x/x, followed by the total number of teeth. The abbreviation “I” means incisors, “C” canines, “P” premolars, and “M” molars. Letters in uppercase refer to upper teeth, while in lowercase to lower teeth. The dental descriptions presented were based on adult specimens, unless noted otherwise.

RESULTS

Five genera of Canidae, three of Felidae, four of Mustelidae, one of Mephitidae, and five of Procyonidae have species occurring in Brazil (Table I). All examined specimens have on each quadrant three incisors, located on the pre-maxilla, and one canine, the first tooth on the maxilla. However, the number of premolars and molars vary, and are presented below separately by family.

Canidae

All examined members of the family Canidae, except Speothos venaticus (Lund 1842), display the dental formula I 3/3, C 1/1, P 4/4, M 2/3 = 42 and the same general dentition pattern (Fig. 1a). Upper premolars increase in size posteriorly, and the carnassial (P4) is the largest tooth with the highest cusps. The two molars are enlarged buccolingually and have complex crowns composed of four main cusps, and crests arranged in two parallel lines; M2 is smaller than M1. In the lower toothrow, premolars also increase and molars decrease in size posteriorly. The first molar is always the largest postcanine tooth, with carnassial blades positioned mesially on the trigonid, and three low cusps distally on the talonid.

Figure 1
Occlusal (top) and lateral (bottom) views of the skull and mandible of: a) Atelocynus microtis (MN650); b) Speothos venaticus (MN25670). Abbreviation “I” means incisors, “C” canines, “P” premolars and “M” molars. Scale bar = 2cm.

Speothos venaticus (Fig. 1b) is the only Brazilian canid with just one upper and two lower molars, i.e., I 3/3, C 1/1, P 4/4, M 1/2 = 38. S. venaticus also shows simplification on m1 (lower carnassial) by both losing the metaconid and having a single-cuspidate talonid, while the m1 of other canids have five cusps. Finally, the second lower molar of S. venaticus has a single cusp. Nevertheless, one specimen of S. venaticus (MN75089), representing 20% of the examined individuals, has two upper molars in both sides of the jaw instead of one (Fig. 2a). This additional molar is extremely small, peg-like, and without distinguishable cusps.

Figure 2
Canidae dentitions. a) Ventral view of a partial skull of Speothos venaticus (MN75089) with two upper molars instead of one; b) Ventral view of a Cerdocyon thous skull (MN79593) with an extra premolar positioned lingually to left carnassial; c) Ventral view of a C. thous skull (MN71092) with three upper molars instead of two; d) Mandible of C. thous (MN79393) in occlusal view with four lower molars on the right side and three on the left side; e) Occlusal (top) and lateral (bottom) views of a juvenile C. thous exemplar (MN81779) showing small pits positioned lingually to incisors, canines and premolars, through where permanent teeth would have erupted and replaced the deciduous ones. Note that P1 and P2, P3, P4 have unsynchronized eruptions, and dP3 and dP4 resemble a carnassial and a molar, respectively. Abbreviation “P” means premolars and “M” molars. Scale bar = 2cm.

Specimens of Cerdocyon thous (Linnaeus 1766) and Lycalopex spp. also have supernumerary teeth. In one C. thous specimen (MN79593), one extra tooth, probably a premolar, is found positioned lingually to the left upper fourth premolar (Fig. 2b), and its shape and position resemble a common carnassial. Two specimens have a third upper molar, one of them (MN25683) possessing a M3 alveolus (but no tooth) distally to the right M2, while the other (MN71092) had a pair of M3’s of equal size (Fig. 2c). On the lower jaw, three specimens (MN79393, MN79509, MN81791) have a tiny right fourth molar (Fig. 2d), and one specimen (MN25601) showed an alveolus distal to the left m3. A single specimen of C. thous (MN25579), representing 0.65% of our sample, did not have the m3, showing I 3/3, C 1/1, P 4/4, M 2/2. Finally, one unidentified specimen of Lycalopex (MN652) showed an extra pair of upper molars (M3).

Eleven juvenile specimens of C. thous (Fig. 2e) were employed to assess shedding and replacement patterns among canids (appendix 1). We could not find any evidence of shedding of the first postcanine tooth even among the youngest exemplars, although we found replacement evidence of all other premolars. The second deciduous premolar possesses the same general shape of the permanent one, while the third deciduous premolar has a carnassial shape, and the fourth one has a molar shape. Unfortunately, no juvenile specimen of S. venaticus was available for description.

Felidae

Brazilian cats usually have the traditional felid permanent dental formula I 3/3, C 1/1, P 3/2, M 1/1 = 30 (Fig. 3a). On the upper jaw, the three premolar teeth increase in size posteriorly. A conspicuous carnassial is the largest premolar in adult specimens, although the predecessor tooth has a cusp with almost the same height. A single reduced molar, simple in form and without conspicuous cusps, is hidden by the carnassial in lateral view. On the lower jaw, the three postcanine teeth have the same height, but the first two, the premolars, have just one higher cusp each, while the molar has two cusps and crests, typical of a carnassial. This molar lacks a conspicuous talonid.

Figure 3
Occlusal (top) and lateral (bottom) views of the skull and mandible of: a) Leopardus wiedii (MN5114); b) Panthera onca (MN32376). Note the small pits positioned lingually to the incisors, canines and premolars (arrow) on both upper and lower jaws, through where the permanent dentition would have erupted. The third and fourth deciduous premolars resemble the shape of permanent fourth premolar and first molar, respectively. Abbreviation “P” means premolars and “M” molars. Scale bar = 2cm.

Individuals of several species depart from this pattern. Of the three examined specimens of Leopardus braccatus (Cope 1889), two (MN4868, MN24904) have just two upper premolars, and one specimen (MN63629) has three upper premolars on one side and two on the other side. Four specimens (MN3133, MN49354, MN79565, MN84552) of L. tigrinus (Schreber 1775) also have just two upper premolars, representing approximately 14% of all examined specimens. Finally, one specimen (MN5679) of L. pardalis (Linnaeus 1758) has three premolars on the lower jaw, and one (MN48869) of Panthera onca (Linnaeus 1758) has three premolars on one hemimandible.

Four juvenile specimens of P. onca (Fig. 3b; appendix 1) have a series of perforations close to the base of incisors, canine, and premolars, indicating shedding. The carnassial shape of the third upper deciduous postcanine and the molar shape and size of the fourth upper deciduous postcanine reinforce that these teeth are the last premolars. These perforations are also found close to the lower teeth.

Mephitidae

Conepatus is the single genus of the family Mephitidae that occurs in Brazil; its members have a typical dental formula of I 3/3, C 1/1, P 2/3, M 1/2 = 32 (Fig. 4a), but one specimen (MN30000) of C. semistriatus (Boddaert 1785), among a total of six, has three upper premolars. Postcanines increase in size posteriorly, with the first premolar tooth with only one cusp and the last premolar with two cusps forming the traditional carnassial blade. The last tooth, the molar, is the largest one.

Figure 4
Occlusal (top) and lateral (bottom) views of the skull and mandible of: a) Conepatus semistriatus (MN13385); b) Lontra longicaudis (MN22255). Abbreviation “P” means premolars and “M” molars. Scale bar = 2cm.

On the lower jaw, premolars increase in size posteriorly, and the three premolars have a single cusp each. Molars decrease in size posteriorly, and the lower carnassial (m1) is the largest mandibular teeth, with its talonid larger than its trigonid. The m1’s talonid of Conepatus specimens was the largest among all examined Carnivora. The second molar is more squared, without conspicuous cusps.

The total sample size of C. chinga (Molina 1782) and C. semistriatus consisted of seven individuals, and no juvenile specimen with deciduous teeth was available for examination. An enlarged series is needed to ascertain the variation in this genus.

Mustelidae

The permanent dental formula of mustelids is the most variable among Brazilian terrestrial carnivores. Every mustelid has three incisors, one canine, and one upper and two lower molars, but the number of premolars varies. Specimens of Pteronura brasiliensis (Gmelin 1788) and Lontra longicaudis (Olfers 1818) have I 3/3, C 1/1, P 4/3, M 1/2 = 36 (Fig. 4b). The premolars increase posteriorly in size, and are very close to each other. The first premolar is positioned lingually to the canine, being almost hidden by the latter in lateral view. The last upper premolar, the carnassial, is a very large tooth, larger than the single upper molar. On the lower jaw, one incisor is positioned behind the other two in each quadrant. The three premolars increase posteriorly in size, but only slightly. The first molar, the carnassial, is the largest lower tooth, with a trigonid as large as the talonid. The last molar is small without conspicuous cusps.

The only variation found among otters was a specimen (MN70163) of L. longicaudis with P 3/2, creating a diastema between these teeth and the canines.

The examination of two skulls of juvenile specimens of L. longicaudis (Fig. 5a; appendix 1) shows that the first upper postcanine teeth are not replaced, at least not at the same time as others. This tooth is followed by three postcanine teeth that are replaced. Therefore, these four teeth are all premolars, and are succeeded by one molar. In Lontra, the third and fourth deciduous upper premolars assume the form of carnassial and molar teeth, respectively.

Figure 5
Occlusal view of the skull and mandible of juvenile specimens of a) Lontra longicaudis (MN684); b) Eira barbara (MN74385). Note the pits close to the base of each tooth (arrows), indicating replacement, except in P1 of L. longicaudis. Also note the carnassial and molar shapes of third and fourth premolars. The molar is about to erupt in these individuals. Scale bar = 2cm.

Individuals of Eira barbara (Linnaeus 1758) and Galictis spp. have the dental formula I 3/3, C 1/1, P 3/3, M 1/2 = 34 (Fig. 6a). This pattern is very similar to that of Pteronura and Lontra, with the exception that the former taxa do not have the first upper premolar. A tiny unpaired M2 was found in one individual (MN75066) of G. vittata (Schreber 1776). In three juvenile specimens of E. barbara examined (appendix 1)¸ three upper deciduous premolar teeth are shed and replaced (Fig. 5b). The third and fourth decidual premolars in E. barbara depict carnassial and molariform shapes, respectively.

Figure 6
Occlusal (top) and lateral (bottom) views of the skull and mandible of a) Galictis cuja (MN29998); b) Mustela africana (MN29979). The lateral view of M. africana skull was mirrored horizontally to facilitate understanding. Abbreviation “P” means premolars and “M” molars. Scale bar = 2cm.

Individuals of Mustela africana Desmarest 1818 have I 3/3, C 1/1, P 2-3/2, M 1/2 = 30-32 (Fig. 6b). Of the four examined specimens, two had two upper premolars and the other half had three upper premolars. Again, the dental pattern is similar to previous Mustelidae taxa, although the loss of one or two upper premolars creates a diastema between the remaining premolars and the canine. Additionally, the loss of one lower premolar creates a diastema between the remaining premolars, and between premolars and canines. There were no juvenile specimens of M. africana available for examination.

Procyonidae

Two dental formulae are observed among members of this family, both with the same number of teeth on upper and lower jaws: I 3/3, C 1/1, P 4/4, M 2/2 = 40 (Fig. 7a), as seen in Bassarycion alleni Thomas 1880, Nasua nasua (Linnaeus 1766) and Procyon cancrivorus (G. Cuvier 1798); and I 3/3, C 1/1, P 3/3, M 2/2 = 36 (Fig. 7b), observed only in Potos flavus (Schreber 1774). As usual, premolars increase and molars decrease in size posteriorly. The last upper premolar does not depict the form of the typical carnassial tooth but, instead, is very similar in size and shape to the first molar. The first molariform tooth, thus, is the last premolar, which is preceded by three premolariform premolars and succeeded by two molars. The typical carnassial shape is also missing on the lower jaw.

Figure 7
Occlusal (top) and lateral (bottom) views of the skull and mandible of: a) Procyon cancrivorus (MN28802); b) Potos flavus (MN68610). Abbreviation “P” means premolars and “M” molars. Scale bar = 2cm.

The examination of 14 juvenile specimens of N. nasua (appendix 1) shows that the first postcanine tooth does not shed, while the three following postcanine teeth are replaced; this reinforces the premolar identity of these postcanine teeth on upper and lower jaws. The remaining two teeth are molars, which are not replaced. The examination of five juvenile specimens of P. flavus (appendix 1) shows that the first three postcanine teeth are replaced with permanent ones (i.e., are premolars), and the last two teeth are molars.

DISCUSSION

The data presented here contrast with the dental formulae proposed by some of the most important books about Neotropical mammalian fauna (e.g.: Eisenberg 1989, Emmons & Feer 1997, Eisenberg & Redford 1999, Labate et al. 2001, Cheida & Santos 2010). All consulted books have one or more mistakes about carnivores’ dental formula, as discussed below. Thus, we propose a concise identification key based on the correct formulae and teeth morphology of Brazilian carnivores (see appendix 2).

Canidae

Our study corroborated that individuals of all taxa of this family, except for S. venaticus, have two upper molars as previously observed by Eisenberg (1989), Emmons & Feer (1997), Eisenberg & Redford (1999), and Cheida & Santos (2010). In contrast, Pessutti et al. (2001) wrongly proposed that Brazilian Canidae has three upper molars. The loss of the third upper molar is a synapomorphy of Carnivora (Wesley-Hunt & Flynn 2005). Additionally, the loss of one additional molar on both upper and lower jaws in Speothos venaticus, resulting in M 1/2, was neglected by Pessutti et al. (2001).

Eisenberg (1989) and Eisenberg & Redford (1999) suggested that specimens of S. venaticus have one or two upper molars, while Sillero-Zubiri (2009) proposes two upper molars for this species. There is a report of one S. venaticus specimen from Guyana that has two upper molars (Flower 1880). This author suggested that this could be the first examined specimens to have M 2/2 and mentioned that the variation found could be a peculiarity of this specimen, or a tooth commonly lost in older adults. Those findings, coupled with our present results, indicate a polymorphism in this species. As only one specimen among five examined here has two upper molars, the basic dental formula of S. venaticus is considered as I 3/3 C 1/1 P 4/4 M 1/2. Additionally, Speothos pacivorus (Lund 1839), a fossil form, was redescribed by Berta (1984) with P 4/4 and M 2/2. This author mentions that M2 is rarely present in S. venaticus and that this is one important difference between the extant and extinct species. Without mentioning the dental formula, Paula-Couto (1953) suggested that the total tooth number in Speothos may vary between 36 and 40, but the evidence indicate a variation between 38 and 40 teeth.

Sillero-Zubiri (2009) reported that Cerdocyon thous has one upper and two lower molars and a total of 44 teeth, contrary to our observation of two upper and three lower molars and a total of 42 teeth. Although C. thous showed a slight variation in the dental formula, resulting in 40, 42, 43 or 44 teeth, we did not find a single specimen with the formula mentioned by Sillero-Zubiri (2009).

Felidae

Individuals of Neotropical Felidae genera have two or three upper premolars according to Eisenberg (1989), Emmons & Feer (1997) and Eisenberg & Redford (1999). The authors did not mention which species has one or another dental formula, and the few skull drawings in the Eisenberg (1989) and Eisenberg & Redford (1999) show three upper premolars. Garcia-Perea (1994), however, found that among eight examined specimens of Leopardus braccatus (previously considered part of L. colocolo), only three had two premolars on the upper jaw. Of three L. braccatus examined here, only one (MN63629) has an unpaired second premolar on the right side, and no sign of this tooth or alveolus on the left side; the remaining two specimens (MN4868, MN24904) have only two premolars. L. tigrinus also has specimens (MN3133, MN49354, MN79565, MN84552) with just two pairs of premolars on upper jaw. Specimens of L. wiedii (Schinz 1821), Puma concolor (Linnaeus 1771), and Panthera onca consistently have three upper premolars.

Regardless of the variation in upper premolars, there are always two premolars on the lower jaw in all examined Felidae specimens, contradicting Cheida & Santos (2010) proposal of P 3/3. The dental formula suggested by Cheida & Santos (2010) seems to be a misrepresentation, since the total number of 30 teeth proposed by them fits the formula I 3/3, C 1/1, P 3/2, M 1/1 as suggested here, and not with the formula involving P 3/3.

Mephitidae

Exemplars of the two species of Conepatus have P 2/3 and M 1/2, but previous compendia included the taxon among the Mustelidae and wrongly provided its dental formula as the same for that family, P 3/3 and M 1/2 (Eisenberg 1989, Emmons & Feer 1997, Eisenberg & Redford 1999, Pimentel et al. 2001); only Cheida & Santos (2010) correctly proposed Conepatus dental formula. Nevertheless, one of the eight specimens examined here has three upper premolars. Van Gelder (1968), based on museum vouchers, reported the formula for Conepatus chinga from Uruguay as I 3/3, C 1/1, P 2/3, M 1/2. The author also reported that a few specimens (number not mentioned) among the 103 examined had three upper premolars, stating that this is not common and that the usual formula involved only two upper premolars.

Mustelidae

The general dental formula of Neotropical mustelids is I 3/3, C 1/1, P 3/3, M 1/2, except for the Lutrinae taxa Lontra longicaudis and Pteronura brasiliensis, which is P 4/3. Previous works have only reported the general formula for the family (Eisenberg 1989, Eisenberg & Redford 1999, Pimentel et al. 2001), but Cheida & Santos (2010) also reported the formula of Pteronura brasiliensis as found here.

Emmons & Feer (1997) described variation on the family’s postcanine dental formula as P 3-4/3-4, M 1/1-2, but it is not possible to infer if the variation in the number of premolars and molars is intraspecific, interspecific, or even intergeneric. More importantly, although our sample is small for some of the examined taxa and does not include Mustela frenata Lichtenstein 1831, we did not find a single specimen with four lower premolar or with only one lower molar, as suggested by these authors. Even the inclusion of Conepatus within the Mustelidae, as followed by Emmons & Feer (1997), would not explain the formula variation.

The dental formula of Mustela africana described here differs from the general family trend and agrees with that of Ramírez-Chaves et al. (2014), which reported the variation in premolar number P 2-3/2, M 1/2. These authors suggest that this dentition is specialized for a carnivorous diet, although nothing is known on this matter (Larivière & Jennings 2009) or any other aspect of its biology (Oliveira 2009). Eira barbara has an omnivorous diet (see Presley 2000 for revision), while Galictis vittata is predominantly carnivorous (see revision in Yensen & Tarifa 2003). These two mustelid taxa, with three premolars, have different diets and the same dental formula, a similarity that could be a result of phylogenetic constraint. Unfortunately, the lack of resolution for most carnivores’ phylogenetic trees precludes a proper test of this hypothesis (Popowics 2003).

Procyonidae

There is an agreement about the constancy of the dental formula for most Brazilian Procyonidae (Eisenberg 1989, Emmons & Feer 1997, Eisenberg & Redford 1999, Labate et al. 2001, Cheida & Santos 2010). The formula I 3/3, C 1/1, P 4/4, M 2/2 = 40 is largely accepted for Procyonidae, although an exception is known for Potos flavus. Eisenberg (1989), Eisenberg & Redford (1999) and Cheida & Santos (2010) agree that P. flavus specimens have P 3/4 and M 2/2, while Emmons & Feer (1997) and Labate et al. (2001) suggest P 3/3 and M 2/2; the dental formula found here for P. flavus supports the latter authors. The difference in dental formula between P. flavus and other examined Procyonidae could be related to different diets: while Potos flavus is mainly frugivorous, the remaining Neotropical procyonids are mostly omnivorous (Kays 2009).

The family Procyonidae contains more omnivorous species when compared to the other examined families (Kays 2009). This is evident in the general form of the last premolar, which is molariform without the prominent blades of common carnassial (Hillson 2005). Consequently, this family has no clear morphological distinction between premolars and molars. On the other hand, the number of six postcanine teeth can be used to infer the identity of each tooth. As the total number of premolars in ancestral forms are four (Cifelli 2000), and members of the order Carnivora have lost the third upper molar (Wesley-Hunt & Flynn 2005), the six postcanine teeth are necessarily four premolars and two molars on the upper jaw.

CONCLUSIONS

We found inconsistencies between our review and dental formulae described in several widely used books on Neotropical mammalogy. In turn, our results also corroborate previous descriptions based on vouchered material. Our review shows that several incongruences were replicated in these books for the lack of examination of museum vouchers, propagating erroneous information without critical analysis. This calls the attention for misleading information about fundamental systematic characters of these flagship species and reinforces the importance of scientific collections as the primary source of phenotypic data.

ACKNOWLEDGMENTS

We are grateful to Gisela Sobral, Marcos Cruz and Emily Bouza for the critical review of this manuscript and to João Alves de Oliveira, who allowed the access to the mammal collection of Museu Nacional/UFRJ. We also would like to thank Cibele R. Bonvicino for support of the project, and the thoughtful reviewers. This research was supported by grants from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior to FG [CAPES 88882.183261/2018-01] and the Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil (CNPq) and Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) to MW [CNPq 481286/2011-0, CNPq 440663/2015-6 and FAPERJ E-26/110.505/2012].

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APPENDIX 1

List of examined specimens; all specimens are composed by skull and mandible and are housed at Museu Nacional/UFRJ (MN/UFRJ). Marked (*) individuals indicate juvenile specimens, i.e., with a deciduous tooth; those not marked are all adult individuals, i.e., those with full permanent dentition.

Canidae

Atelocynus microtis: MN650.

Cerdocyon thous: MN-JFV321, MN-JFV334, MN-P1, MN-PRG1370, MN670*, 932, 1364, 1389*, 3036, 3038, 3885, 3887, 4242-4243, 4891, 4908, 5496, 5505, 5881, 7576, 8469, 8479, 10986-10987, 10993, 11205, 11397*, 25005, 25551-25554, 25556, 25559-25560*, 25570, 25577-25579, 25580*, 25581*, 25582-25584, 25585*, 25586*, 25587, 25589-25594, 25597-25603, 25605-25608, 25612, 25683, 25688, 26775, 29061-29062, 30584, 30586, 32370-32371, 36759, 37658, 41227, 42800, 43968, 46810, 46853, 47670, 55054, 59010, 61838, 63471, 63491, 63505, 63517, 64258, 64573, 64685, 67574, 68181, 68361, 68367, 68370*, 68385, 70835, 70858, 71067*, 71084, 71092, 71155, 72784, 73473, 75036, 75086, 75090, 75092, 75981, 79026, 79109-79110, 79168, 79172, 79193, 79196, 79225, 79243, 79252, 79288, 79292, 79359, 79377, 79393, 79398-79399, 79408, 79410, 79414, 79418, 79460, 79464, 79475, 79483, 79485, 79486, 79509, 79515, 79547, 79563, 79578, 79593, 81068, 81779*, 81788, 81791, 83590, 83601-83602, 83630-83631.

Chrysocyon brachyurus: MN640, 664, 1049, 3041*, 3049*, 3055, 4815, 4899*, 17501-17502, 32372, 36666, 62552, 68175, 69817, 70999, 71086, 79031*, 79113, 79117, 79195, 79386, 79396, 79411, 79481.

Lycalopex vetulus: MN651, 655-656, 3037, 3039-3040, 3044, 4241, 4909, 5151, 32428, 68180, 71039, 71045, 71047, 71093, 71112, 71160, 71173, 72779*.

Lycalopex gymnocercus: MN2355.

Lycalopex sp.: MN652.

Speothos venaticus: MN3033, 3035, 25668, 25670, 75089.

Felidae

Leopardus braccatus: MN4868, 24904, 63629.

Leopardus pardalis: MN620-622, 624-625, 3156, 4811, 4817, 5679, 7630, 24875-24876, 24880-24884, 25691, 25693, 48873-48878, 48880, 68156, 71609, 79122, 79273, 79291, 79557, 79558, 83607, 84555, 84557.

Leopardus tigrinus: MN610, 1363, 1690, 3133, 5145, 5885, 6693, 7261, 24894-24896, 25650-25651, 25653, 25726, 49354, 49356, 71153, 74386, 79051, 79465, 79480, 79565, 79583, 84550, 84552-84554.

Leopardus wiedii: MN1382*, 5114*, 5621, 6066*, 18813, 24886-24887, 24890*, 24910*, 25723, 72785, 79530.

Panthera onca: MN-TX69, MN633-634, 1007, 1013, 1015, 1017, 1021, 1022*, 1023, 3349, 13508, 24858*, 24860-24863, 32375*, 32376*, 32705, 32707, 36218, 48868, 48869, 71161, 77863.

Puma concolor: MN381, 985, 1014, 1016, 1018-1020, 1025, 1029, 3351, 6022-6023, 17506, 24865, 24867, 24869, 24872*, 49074-49075, 53862, 71077, 71085.

Puma yagouaroundi: MN384, 1039, 1043, 1381, 3140-3141, 3153, 4893, 24885, 24901-24902, 49076, 49316, 75985, 79049, 79158, 79280, 79329, 79490, 79548.

Mephitidae

Conepatus chinga: MN3128.

Conepatus semistriatus: MN1500, 13385, 29990, 30000, 59335, 63316.

Mustelidae

Eira barbara: MN669, 3100, 3102, 3106-3107, 4904, 4906-4907, 5163*, 5512, 5619*, 5649, 5791, 5959-5960, 6085, 6088-6089, 7611, 10990, 25686, 29976, 29977, 30003, 51650, 63452, 68357-68358, 68365, 68625, 74385*, 75096, 79526.

Galictis cuja: MN677, 687, 1160, 1498-1499, 1506, 1755, 1882, 3127, 3129, 3131, 4845, 5809, 7258, 7322, 8236-8238, 10508, 11181-11183, 25684, 29980-29988, 29998-29999, 30001, 42018, 43947, 69904, 79190, 79216, 79314, 79379, 79510.

Galictis vittata: MN3093, 3115, 29989, 29993, 75066.

Lontra longicaudis: MN684*, 3020, 3023, 3031, 22255, 25680, 25682, 30002, 50799-50800*, 69898, 70163, 79200, 81789.

Mustela africana: MN3121-3122, 29979, 66495.

Pteronura brasiliensis: MN3024, 32700, 42695, 50801, 50802*, 50803, 73635, 77231.

Procyonidae

Bassaricyon alleni: MN69145, 69149-69150.

Nasua nasua: MN-MOL30, MN358-361, 363-365, 367, 999, 1418, 3050, 3062, 3064-3065, 3068, 3073, 3075-3076, 3081-3084, 3096, 3099, 3841-3844, 4048, 4074, 4717, 4861, 4879, 4883-4888, 4892, 4901, 4905, 4911-4912, 5205*, 5506, 5622, 5628, 5633, 5709, 5723, 5727*, 5810, 5872*, 5925-5926, 5942, 6033*, 6034, 6067, 6087, 6695, 6697, 7263, 7311, 7626-7627, 7658*, 8482, 8504, 11605, 23876-23883, 24783*, 24786-24788*, 24798-24799*, 24801, 24804-24809, 24812-24813, 24814*, 24815-24818, 24822, 24824, 24826, 25679*, 25699, 28502*, 32388-32389, 32392-32393, 32395-32396, 32398, 32431, 32436*, 37630, 64002, 64006, 64068, 65558, 66177-66180, 71046, 71064, 71071, 71157, 71159, 72361*, 73169*, 75084, 79047, 79123, 79293, 79349, 79392, 79549.

Potos flavus: MN-M18096, MN1078, 3089, 3098, 4851, 4862*, 4866, 4867*, 4874, 4876-4877, 4880*, 4881, 4902-4903, 5162, 5617, 5639, 5689, 5714, 5716, 5721-5722, 5774, 10965-10972, 10992, 11396, 24925, 32391*, 32406-32423, 55500, 68610, 69118, 69129, 69298*.

Procyon cancrivorus: MN1044, 1497*, 3087, 3094, 4896-4897, 5503-5504, 5643, 7256, 7577, 7612, 7625, 11203, 23884-23887, 25310, 25657, 25689, 28802, 32374, 32377-32378, 32380-32382, 32384, 41102, 64438, 65559, 71087, 71090, 75093, 79170, 79344, 79540, 79568, 81067, 83591-83593.

APPENDIX 2

Publication Dates

• Publication in this collection
  19 July 2021
• Date of issue
  2021

History

• Received
  11 Nov 2019
• Accepted
  21 Oct 2020