THOMPSON: Humboldtiana from Chihuahua and Texas
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Table 6. Humboldtiana titania n. sp. Measurements in mm based of the holotype (UF 358679) and 14 paratypes (UF 317163/10, UF 358376/4).
 H W AW AH Whorls H/W AW/W AH/H AW/AH
Holotype 32.1 35.1 19.2 24.9 4.2 0.83 0.55 0.83 0.80
Paratypes 
Min 26.3 30.7 16.3 21.0 4.1 0.80 0.51 0.71 0.77
Max 32.7 39.2 20.7 26.0 4.5 0.94 0.57 0.84 0.87
Avg 29.90 35.20 18.99 23.44 4.30 0.85 0.54 0.79 0.81
SD 1.87 2.43 1.13 1.58 0.10 0.04 0.01 0.04 0.04
Type locality. Chihuahua, Sierra Victorino, 0.6 km southeast of Cumbres Majalca Visitors Center (2848.1'N, 10628.8'W), ca. 21 km west of Nueva Majalca; 2060 m alt. Holotype: UF 358679; collected 7 August, 2003 by F. G. Thompson and E. L Mihalcik. Paratypes: UF 358376 (4), UF 317163 (10), ITCV (10); same data as the holotype.
Distribution. This species is known only from the type locality.
Ecology. The type locality was sparsely forested with oak and a few scattered pines. Snails were collected along a granite ledge. Dead shells were common along the base of the outcrop. Five live specimens were found aestivating deep within crevices from where they were extracted with great difficulty.
Remarks. The reproductive anatomy of this species is best described as stout in all aspects.
Etymology. The species name titania is from the Classical Literature, Shakespeare, Wm, 1594, A Mid Summer Night Dream. Titania is the exquisitely beautiful fairy queen. The name of this species alludes to the beauty of its shell.
Humboldtiana oberon n. sp.
Diagnosis. The shell is recognized in part by its rich brown ground color with three bold bands and numerous transverse enamel-like white streaks, and by its pink peristome. The surface of the shell is smooth, though interrupted by rather coarse incremental striations and wrinkles. The shell is similar to Humboldtiana titania, but it is smaller, and it has a more rotund aperture. It differs further by having stronger transverse wrinkles on the embryonic whorls, by lacking granular sculpture, by being more coarsely wrinkled on the postembryonic whorls, and by having more densely packed transverse white streaks. The genital atrium is almost non-existent. The penis is very short and contains a verge that is almost the length of the penis. The penis retractor muscle
is relatively slender and is about as long as the combined length of the penis + epiphallus. The flagellum is about 1.5 times longer than the combined length of the penis + epiphallus. The vagina is slender. The dart-glands are widely separated from the dart-sacs. The dart-sacs are subequal in size; ds, is the largest. The head-foot is grayish black in life, and the animal does not exude a distinct odor.
Shell (Figs. 46-49). The shell is medium to large in size, usually about 25-30 mm wide, but occasional specimens are up to 38 mm wide. It is helico-globose in shape, and is 0.79-0.88 times as high as wide. There are 4.0-4.2 whorls, which are inflated and are separated by a deep suture. The periostracum is smooth but nearly lusterless. The shell has three bold nearly black bands. The ground color in fresh specimens is light brown. The last quarter whorl has a rusty tinge. The ground color and the bands are crossed by numerous transverse enamel-like white streaks and elongate blotches that are located on the growth wrinkles, producing a very hansom appearance to the shell. The peristome is pink. The interior of the aperture is light brown and is banded. The umbilicus is obliquely rimate (Fig, 49). The embryonic shell contains 1.4 whorls that are raised and rounded. The first embryonic whorl is 4.1 mm wide perpendicular to the initial suture. The embryonic whorls are sculptured with relatively wide but vague wavy transverse wrinkles. The postembryonic whorls are crossed by numerous incremental striations and growth wrinkles. Distinct granular sculpture is absent on the embryonic and postembryonic whorls, although occasional growth wrinkles on early whorls may be weakly beaded. The last quarter whorl descending strongly to the aperture. The upper lip inserts on or below the lower band. The aperture is oblong-ovate in shape; 1.03-1.22 times as wide as high, and lies at about 30-35 to shell axis in lateral profile (Fig. 47). The peristome is uniformly, weakly and narrowly reflected. The reflected columellar lip nearly obscures the umbilicus.