Cabassous unicinctus ( Linnaeus, 1758 )

Feijó, Anderson & Anacleto, Teresa Cristina, 2021, Taxonomic revision of the genus Cabassous McMurtrie, 1831 (Cingulata Chlamyphoridae), with revalidation of Cabassous squamicaudis (Lund, 1845), Zootaxa 4974 (1), pp. 47-78 : 63-65

Cabassous unicinctus ( Linnaeus, 1758)

Amazon naked-tailed armadillo

Dasypus unicinctus Linnaeus, 1758:50 . Type locality “Africa”. Restricted to Suriname by Thomas (1911:141).

Dasypus duodecim cinctus Schreber, 1774 :Pl. lxxv. Aredrawing of Buffon’s “Le Kabassou ” (1763:Pl. xl), from Cayenne, French Guiana ( Wetzel et al. 2008:152).

[ Dasypus] octodecimcinctus Erxleben, 1777:113-114 . Type locality “America australi”.

Dasypus undecimcinctus Illiger, 1815:108 . Nomen nudum.

Dasypus multicinctus Thunberg, 1818:68 . Type locality “ Brasilien ”.

Tatusia tatouay: Lesson, 1827:311 . Part; not Loricatus tatouay Desmarest (1804:28) .

Dasypus tatouay: Schomburgk, 1840:34 . Not Loricatus tatouay Desmarest (1804) .

Dasypus gymnurus var. β J. A. Wagner, 1844:171 . Not Tatus gymnurus Olfers, 1818:220 .

D [asypus]. verrucosus J. A. Wagner, 1844:172 -footnote. Type locality “den nördlichen Theil [des tropischen Südamerikas]”. Name based on Buffon’s kabassu ( Wagner, 1855:175).

Xenurus [(Tatoua)] unicinctus: Gray, 1865:378 . Name combination.

Xenurus verrucosus: Fitzinger, 1871:233 . Name combination.

Ziphila lugubris Gray, 1873:23 . BM 55.8.28.7 lectotype selected by Wetzel et al. (2008:152), type locality restricted to Demerara, Guyana.

Xenurus lugubris: Thomas, 1880:402 . Name combination.

Xenurus duodecimcinctus: Jentink, 1888:213 . Name combination.

[ Lysiurus (Lysiurus)] unicinctus: Trouessart, 1898:1146 . Name combination.

[ Lysiurus (Ziphila)] lugubris: Trouessart, 1898:1148 . Name combination.

Tatoua (Ziphila) lugubris: Miller, 1899:6 . Name combination.

C [abassous]. (Ziphila) lugubris: Palmer, 1899:72 . Name combination.

Tatoua unicincta: Miller, 1899:2 . Name combination.

C [abassous]. unicinctus: Palmer, 1899:72 . Name combination.

Lysiurus unicinctus: Goeldi & Hagmann, 1904:98 . Name combination

[ Cabassus (Cabassus)] unicinctus: Trouessart, 1905:820 . Name combination.

Cabassous loricatus: Yepes, 1928:467 . Part; not Dasypus loricatus J. A. Wagner, 1855

[ Cabassous] loricatus: Yepes, 1928:467 . Part; not Dasypus loricatus J. A. Wagner, 1855 .

Xenurus unicinctus: Sanderson, 1949:785 . Name combination.

Cabassous unicinctus: Pine, 1973:50 . Name combination.

C [abassous]. unicinctus unicinctus: Wetzel, 1980:343 . Name combination.

Type material. Linnaeus described Dasypus unicinctus based on four sources: the sixth edition of the Systema Naturae, Seba (1734:47, plate 30, figs. 3 & 4), Ray (1693:235) and Grew (1681:19, plate 1). All specimens described and illustrated in these references have equal status as syntypes ( ICZN 1999: Article 73.2.1).

Seba (1734) described and presented two illustrations of his “ Tatu , seu Armodillo, Africanus ” (plate 30, figs. 3 & 4). Thomas (1911:141) considered the female animal illustrated in fig. 4 as dubious ( Figure 9b ). Wetzel (1980) tentatively treated it as C. u. squamicaudis based on the scaly-tailed appearance, while he considered the male animal depicted in fig. 3 as C. u. unicinctus given it displays a completely naked tail ( Figure 9a ). Both illustrations nevertheless display the diagnostic traits on the cephalic shield (lack of scutes below eyes and cheek) of C. unicinctus that set them apart from C. squamicaudis . On the other hand, the animal described and illustrated by Grew (1681:19, plate 1) refers to an armadillo with the tail completely covered by scutes, which closely resembles a six-banded armadillo Euphractus sexcinctus . The Linnaeus’ concept of D. unicinctus was therefore composite.

To preserve the unambiguous current use of the name, we select the specimen illustrated in the figure 3 of the plate 30 of Seba (1734) as the lectotype of Dasypus unicinctus Linnaeus, 1758 ( Figure 9a ). The illustration depicts an animal with five digits in the manus and feet, 13 movable bands, scutes on the cephalic shield limited to the top of the head, absent below eyes and cheek, and a naked-tailed. All other specimens referred to by Linnaeus should be treated as paralectotypes.

Type locality. The collecting locality of the lectotype is unknown. Seba considered it to be an African armadillo, a clear lapse. Thomas (1911) suggested Suriname as the type locality for most of Seba’s South American animals, given it was the main source of the Dutch collection. Therefore, we suggest “ Suriname ” as the type locality for C. unicinctus .

Diagnosis. C. unicinctus is the second largest species in the genus. The scutes on the cephalic shield (32-48) are restricted to the top of the head, leaving the snout, cheek and region below eyes exposed ( Figure 7 ). The cephalic scutes usually show a concentric organization, surrounding a larger central scute; but few specimens exhibit the scutes organized in parallel lines along the sagittal plane, as also found in C. centralis individuals. The skin of the face is smooth and pinkish. The color of the carapace is dark brownish to blackish, with most of the individuals showing a pale stripe in the edges ( Figure 7 ). The number of movable bands varies from 12-13. The ears are large, dark with smooth or irregular edges. The venter is pale with some individuals showing a conspicuous dark spot in the central area ( Figure 7 ). Tail with small scutes sparsely distributed mainly in the dorsal face. In some specimens (31%) the tail exhibits a whitish tip.

Geographic distribution. C. unicinctus occurs in the Amazon forest eastern of Andes, extending from Bolivia, Peru, Ecuador to Colombia, Venezuela, Guianas and Brazil. Its eastern limit coincides with the Caatinga, Cerrado and Chaco biomes in Brazil and Bolivia. This species possibly occurs in the Babaçu forest at the transition zone between Amazon and Cerrado biomes in the northern portion of the Maranhão state ( Figure 8 ). The few records in open areas seem to be related to forested patches or riparian forests. For example, C. unicinctus has been recorded in the savanna llanos of Venezuela and in Brazilian Cerrado ( Figure 1 ), but in all cases they were found in transitional areas between forest-open biomes or in forest corridors along rivers ( Anacleto et al. 2013). It is also possible that C. unicinctus eventually explore adjacent open areas during foraging activities or when the land floods.

Remarks. Cabassous unicinctus is sometimes misidentified as immature Priodontes maximus because of its large claws and whitish stripe in the lateral of the carapace. The two species can be easily differentiated by the tail fully covered by conspicuous osteoderms in P. maximus .

The eastern limit of C. unicinctus unicinctus [here treated as a monotypic species] was defined as the Amazonas-Solimoes rivers by Wetzel (1980), followed by Anderson (1997), Wetzel et al. (2008) and Hayssen (2014a). However, the individuals from eastern Amazon (Pará, Brazil; Beni, Bolivia) identified as C. u. squamicaudis by Wetzel (1980) proved to be C. unicinctus (see Appendix I).

Figures

FIGURE 1. Localities of the Cabassous specimens examined in the study.

FIGURE 7. External morphological differences between C. unicinctus and C. squamicaudis. Note the distinct color of the carapace and face between species. C. unicinctus has a paler venter, and usually, exhibits a dark central spot. In this species, scutes are absent below the eyes, in the cheek region, and in the anterior portion of the snout. Photos by Murilo Passarelli and Teresa Cristina Anacleto.

FIGURE 8. Distribution of the five living species of Cabassous in the Neotropical region. Question marks represent unconfirmed occurrence.

FIGURE 9. (a): Lectotype of Cabassous unicinctus (Linnaeus, 1758) herein designed. Illustration reproduced from plate 30, figure 3 of Seba (1734). (b): Paralectotype of Cabassous unicinctus (Linnaeus, 1758). Illustration reproduced from plate 30, figure 4 of Seba (1734).