Holospira
Holospira is a genus of air-breathing land snails, terrestrial pulmonate gastropod molluscs in the family Urocoptidae. "Holospira" is the type genus of the subfamily 'Holospirinae Pilsbry, 1946'. Etymology. "Holos" (ὅλος) from Ancient Greek means "‘whole’" or "‘entire’" and "spira" (spīra) from Latin means spire. Shell description. The shell is small, cylindric, terminating above in a conic spire, retaining all the whorls, rimate or perforate. The shell has 11-21 whorls, which are closely coiled. The first 1½ of whorls are smooth. The rest of whorls are smooth, striate or ribbed. The suture is superficial. Body whorl is more  or less built forward. The aperture is small, obliquely pear-shaped, rounded or oval. The peristome is expanded or reflected, continuous and usually free throughout. The columella (internal column) is hollow, variously sculptured or smooth. Anatomy. The foot is small, narrow for its length. The lung is long and narrow. Kidney is very narrowly triangular, being wider at the base, tapering anteriorly, slightly longer than the pericardium. There is apparently no secondary ureter. The buccal mass is small, about twice as long as wide, the oesophagus opening well forward. Salivary glands are not united, and in "Holospira goldfussi" they have  long ducts. The jaw is thin, arcuate, with a wide median projection below or none. The radula is about four times as long as wide, with from 19.1.19 teeth (in "Holospira pilsbryi") to 27.1.27 (in "Holopsira nelsoni"). The genital system is like this: there is an atrium of moderate length, the penis is short, with a very long vas deferens, the retractor muscle (p. r.) being inserted at or just beyond the slightly swollen penis, and proximally attached to the floor of the lung, as usual. The free retractor muscles, attached proximally to the axis at about the junction of  the cone with the cylindrical portion of the shell, are excessively long. Distribution. The geographic range of this genus extends from southern Mexico to Texas, Arizona and New Mexico. These snails are not found in Lower California nor Guatemala on the southeast. Habitat. They are confined chiefly to the elevated plateau, where they live under cacti, etc., in sunny places. These snails can tolerate great heat. Henry Augustus Pilsbry (1903) states, that living specimens of "Holospira strobeliana" and "Holospira nelsoni" survived immersion in boiling water for some minutes. Unlike other snails, they did not retract in the water. Species. Species  in the genus "Holospira" include: References. This article incorporates public domain text from reference.