Mustela frenata olivacea Howell
Long-tailed Weasel
Plates [16], [17], [18], [31], [32] and [33]
Mustela peninsulae olivacea Howell, Proc. Biol. Soc. Washington, 26:139, May 21, 1913.
Mustela frenata olivacea, Hall, Carnegie Instit. Washington Publ. 473:104, November 20, 1936.
Type.—Male, adult, skull and skin; no. 180802, U. S. Nat. Mus., Biol. Surveys Coll.; Autaugaville, Autauga County, Alabama; December 22, 1912; obtained by L. S. Golsan.
The skull (plates [16]-[18]), although cracked at two places in the interorbital region, is in one piece and not warped out of shape. The teeth all are present and entire. The skin is exceptionally well made and in perfect condition except for the extreme tip of the tail which is broken off.
Range.—Lower and Upper Austral life-zones in eastern Mississippi, Alabama, Georgia, South Carolina, and northern Florida. See figure [29] on page [221].
Characters for ready recognition.—Differs from M. f. peninsulae in finer, softer pelage and shorter (less than 15.8 in ad. ♀) tympanic bullae; from M. f. noveboracensis, in adult males by wider tympanic bulla which is more than rather than less than 8.5, in adult females by total length which is more than rather than less than 345, and by mastoid breadth which is more than rather than less than distance between articular faces of exoccipital condyle and glenoid fossa; from M. f. arthuri in larger size (adult males with hind foot and basilar length each more than 45); depth of skull at anterior margin of basioccipital, ignoring sagittal crest, amounting to less than 63 per cent of mastoid breadth, and lesser convexity of dorsal outline of skull in longitudinal axis (See pls. 16-18).
Description.—Size.—Male and female: External measurements of adults are available as follows:
| Catalogue No. | Sex | Locality | Total length | Length of tail | Length of hind foot | |
| 47165 | ♂ | Box Springs, Talbot Co., Georgia | 454 | 160 | 48 | |
| 47166 | ♂ | Box Springs, Talbot Co., Georgia | 435 | 147 | 47 | |
| 47167 | ♂ | Box Springs, Talbot Co., Georgia | 422 | 145 | 45 | |
| 41023 | ♂ | Thomas Co., Georgia | 443 | 140 | 47 | |
| 41025 | ♂ | Grady Co., Georgia | 395 | 142 | 47 | |
| 223880 | ♂ | Okefinokee Swamp, Georgia | 416 | 145 | 49 | |
| 198 | ♂ | Okefinokee Swamp, Georgia | 425 | 140 | 48 | |
| Average 7 | ♂ | 427 | 146 | 47 | ||
| 49385 | ♀ | Gainesville, Alachua Co., Florida | 396 | 124 | 45 | [not typical] |
| 41024 | ♀ | Thomas Co., Georgia | 380 | 125 | 41 | |
| 51527 | ♀ | Talbot Co., Georgia | 376 | 128 | 43 |
The length of the hind foot averages less than the basal length in both males and females. The tail averages 52 per cent as long as the head and body in males and 51 per cent in females. Average differences in measurements of the two sexes are: Total length, 49; length of tail, 19; length of hind foot, 5. An adult male, no. 41023, and an adult female, no. 41024, each taken in February, 1929, on the Sinkola Plantation, Thomas County, Georgia, weighed 15 ounces (425 grams) and 7 ounces (198 grams) respectively according to Charles O. Handley.
Externals.—As described in Mustela frenata noveboracensis, except that hairiness of foot-soles slightly less than shown in figure [19].
Color.—Upper parts, in summer, near tone 4 of Burnt Umber of Oberthür and Dauthenay, pl. 304. In winter lighter, between tones 3 and 4 of Raw Umber of Oberthür and Dauthenay, pl. 301. Dark spot at each angle of mouth present or absent. Underparts ranging from Massicot Yellow to Cream Buff except on chin and upper lips which are white. Tip of tail black. Upper parts of uniform color. Color of underparts extends distally on posterior sides of forelegs over antipalmar faces of toes and on medial sides of hind limbs to ankles. Least width of color of underparts averaging, in a series of five males from Talbot Co., Georgia, 29 (extremes 24-34) per cent of greatest width of color of upper parts. Black tip of tail in same series, averaging 65 (extremes 60-70) mm. long, thus longer than hind foot and averaging 43 per cent of length of tail-vertebrae.
The spot at the angle of the mouth is absent in one-third of the specimens examined. The upper lips are white in specimens from the southern part of the range of olivacea but in the northern part of the range of the subspecies the upper lips are dark colored as in noveboracensis.
Skull and teeth.—Male (based on 5 adults from Talbot Co., Georgia): See measurements and plates [16]-[18]; weight, 5.3 (5.0-6.4) grams; basilar length, 48.3 (45.8-50.1); zygomatic breadth more or less (usually less) than distance between condylar foramen and M1 and more or less (usually more) than distance between anterior palatine foramen and anterior margin of tympanic bulla; mastoid breadth more or less than (averaging about equal to) postpalatal length; postorbital breadth less than length of upper premolars and more or less than (about equal to) width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; interorbital breadth more or less than (about equal to) distance between foramen opticum and anterior margin of tympanic bulla; breadth of rostrum less than length of tympanic bulla; least width of palate less than greatest length of P4; anterior margin of tympanic bulla as far posterior to foramen ovale as width of 3 to 5 upper incisors; height of tympanic bulla not less than distance from its anterior margin to foramen ovale; length of tympanic bulla more than length of lower molar and premolar tooth-row and longer than rostrum (one exception); anterior margin of masseteric fossa below posterior half of m2.
Female (based on 2 adults from Thomas Co., Ga., and one from Talbot Co., Ga.): See measurements and plates [31]-[33]; weight, 3.8 (3.5-4.0) grams; basilar length, 43.4 (42.7-44.0); zygomatic breadth less than distance between condylar foramen and M1 or than between anterior palatine foramen and anterior margin of tympanic bulla; postorbital breadth less than length of upper premolars and more or less (usually more) than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; least width of palate less than greatest length of P4; tympanic bulla as far posterior to foramen ovale as width of 3 to 4 (including I3) upper incisors; height of tympanic bulla not less (usually more) than distance from its anterior margin to foramen ovale; length of tympanic bulla more than length of lower molar and premolar tooth-row and longer than rostrum.
The skull of the female averages 28 per cent lighter than that of the male.
Compared with the skull of M. f. peninsulae, of which only one good skull, and that a female, is available, that of M. f. olivacea averages smaller and has relatively and actually smaller and less inflated bullae. As compared with the skull of M. f. noveboracensis, that of olivacea in the case of males is larger in every part measured and relative to the basilar length is broader across the zygomatic arches and mastoids. However, the rostrum and interorbital region are relatively narrower. The orbitonasal length is relatively less. The tympanic bullae are broader and more inflated. The same differences hold as between females of noveboracensis and olivacea. Indeed, the females of these two races differ more than do the males. Additional, selected differential cranial characters in the females are, in olivacea, as follows: Weight averaging 3.8 grams rather than 1.7 grams; braincase with, rather than without, sagittal crest; anterior border of tympanic bulla separated from foramen ovale by breadth of less than, rather than breadth of more than, 4 upper incisors (including I3); height of tympanic bulla not less than, rather than less than, distance from its anterior margin to foramen ovale; squamosal bone, between anterior margin of tympanic bulla and foramen ovale, ventrally concave rather than ventrally convex. Comparisons of the skulls with those of M. f. arthuri and M. f. primulina are made in the accounts of those subspecies.
Remarks.—Excepting two young specimens from South Carolina in the Charleston Museum, no specimens of this race of large weasel seem to have been preserved until Arthur H. Howell, in the course of his study of the mammals of Alabama, procured specimens on which his name, olivacea, was based. Later, Francis Harper obtained three instructive specimens from Okefinokee Swamp. Really adequate material, for the localities represented, owes its preservation to the alertness of Charles O. Handley, when he resided at Thomasville, Georgia, and to Hallie E. Fuller of Geneva, Talbot Co., Georgia.