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BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 46(3)
not visible. Spermathecal duct very long, more than twice the length of the uterus. Type species: Humboldtiana tanymastix n. sp.
3b. Shell with granular sculpture on part or all of shell.
.....................................................................4a
4a. Shell sculpture consisting of large nodular tubercles arranged in short rows transverse to the incremental striations. Embryonic sculpture consisting of fine straight radial striations. Shell shape discoidal. Shell banding
obsolete. Dart-bulbs exposed............................
................Polyomphala Thompson & Brewer, 2000.
Other characters. Mantle uniform dark gray. Verge large, eccentric. Penis retractor muscle inserting on base of epiphallus. Genital atrium abbreviated. Free vagina not apparent. Middle vagina abbreviated; dart-glands juxtaposed to dart-sacs. Spermathecal duct longer than uterus. Type species: Humboldtiana oreina Thompson & Brewer, 2000.
4b. Shell sculpture without large nodes. Embryonic sculpture different. Shell shape helicoid or depressed helicoid. Shell distinctly banded. Dart-bulbs not apparent...............................................................5a
5a. Embryonic sculpture consisting of wavy trasverse stiations and wrinkles Granular sculpture confined to first post-embryonic whorl.....Clydonacme n. subgen.
Other characters. Penis with a short verge that is equal to or less than half the length of the penis. Penis retractor muscle forms a narrow sheath around base of epiphallus. Genital atrium abbreviated. Free vagina short. Dart-glands juxtaposed to, or widely separated from dart-sacs. Spermathecal duct variable in length. Type species: Humboldtiana regula n. sp.
5b. Embryonic whorls smooth. Granular sculpture distributed widely over surface of shell....................
..............................Humboldtiana Von Ihering, 1892.
Other characters. Verge present. Penis retractor muscle inserting on apex of penis or on base of epiphallus. Genital atrium long. Free vagina abbreviated. Middle vagina abbreviated; dart-glands juxtaposed against dart-sacs. Spermathecal duct longer than uterus. Type species: Helix humboldtiana Pfeiffer, 1847.
The subgenus Humboldtiana is difficult to define
because it includes disparate groups of species, which
clearly do not form a single integral unit (Thompson 2006). Most striking of these is the Humboldtiana bicincta species group (Thompson & Brewer, 2000). Its shell characters and reproductive anatomy diverge from patterns that otherwise occur widely within Humboldtiana. Additional study of the subgenus Humboldtiana is required before it can be defined satisfactorily. The new subgenera proposed herein differ by distinct embryonic shell sculpture patters coupled with unique anatomical character states.
Subgenus Humboldtiana von Ihering, 1892
Most species of Humboldtiana have smooth embryonic shells. It is doubtful that the following three species belong to a single subgenus. They are retained within the subgenus Humboldtiana until additional local patterns of species diversity become apparent.
Undetermined species group
Humboldtiana presidii Pilsbry, 1939
Humboldtiana hogeana presidii Pilsbry, 1939: 402; fig. 269f.
Diagnosis. See below, Remarks.
Shell (Figs. 1-7). The shell is medium size, up to 34.3 mm wide. It is depressed sub-globose in shape, and is 0.74-0.85 times as high as wide.. The 1.5 embryonic whorls are nearly flat and smooth. The following half postembryonic whorl has rather close irregular radial striations. The remaining whorls have fine growth wrinkles and striations, but completely lack granular sculpture. The aperture is strongly oblique (Fig. 2). The peristome is weakly reflected along the upper and basal margins, and broadly reflected over the umbilical region so that the shell is obliquely umbilicate (Figs. 3, 6). The color pattern is light brown with three subequal chestnut bands and occasional whitish transverse streaks. The interior of aperture has a whitish glaze and is banded within.
Measurements of the holotype and ten specimens from San Carlos Tunnel, 2.5 mi. N of the Coal Mine Ranch House are given in Table 1.
Anatomy A single specimen was available for dissection (UF 354500). Reproductive system (Figs. 8-11). The genital atrium is very short and hardly distinguishable. The penis is short, 4 mm long, and elliptical-ovate in shape (Fig. 10). The inner wall of the penis is lined with short fleshy pilasters. A stout verge extends half the length of the cavity (Fig. 11). The epiphallus is relatively short and stout, 7 mm long, and is slightly less