MUSTELA AFRICANA Desmarest
Tropical Weasel
(Synonymy under subspecies)
Type.—Mustela africana Desmarest, Nouv. Dict. d'Hist. Nat., vol. 19, p. 376. 1818.
Range.—Known from the headwaters of the Amazon in eastern Perú and from near the mouth of the same river, on its southern side in Brazil, all within the Tropical Life-zone. See figure [29] on page [221].
Characters for ready recognition.—Differs from Mustela frenata, the only geographically adjacent species of the genus, by: presence of thenar pad on forefoot; presence of a longitudinal, median, abdominal stripe of same color as upper parts; upper lips being broadly edged, entirely round, with color of underparts; failure of longest facial vibrissae to reach posterior margin of ear; absence of p2; relative flatness (see pl. 29, fig. i and pl. 39, fig. h) of tympanic bullae.
Characters of the species.—Size large (total length of adults approximately 500 mm.); foot-soles naked; thenar pad present on forefoot; length of claws, measured on concave sides, less than one and one-fourth times depth of claws measured at bases; longest facial vibrissae not reaching posterior margin of ear; tail relatively long haired; tail at all ages terminating in point as is characteristic of only juveniles and very young of Mustela frenata and M. erminea; tip of tail, and muzzle, only slightly darker than remainder of upper parts; upper lips broadly edged with color of underparts; pelage coarse, harsh and sparse; longitudinal, median, abdominal stripe of same color as upper parts present; skull broad and deep; braincase large, rounded, and much inflated anteriorly; palatal region wide; tympanic bullae less inflated than in any other American species of the subgenus; angle of lower jaw reduced; dental formula
3 1 2-3 1
-, -, ---, -;
3 1 2 2
teeth heavy; medial lobe of M1 but slightly larger than lateral lobe. See plates [28], [29], [30], [39] and cranial measurements.
Geographic variation.—The reddish versus chocolate color of the upper parts constitutes the only variation of a geographic nature so far detected.