Holospira

Holospira
Shell of Holospira elizabethae
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Heterobranchia

clade Euthyneura
clade Panpulmonata
clade Eupulmonata
clade Stylommatophora
informal group Sigmurethra

Superfamily: Urocoptoidea
Family: Urocoptidae
Subfamily: Holospirinae
Genus: Holospira
von Martens, 1860[1]
Species

See text

Holospira is a genus of air-breathing, land snails, terrestrial pulmonate gastropod molluscs in the family Urocoptidae.

Drawing of the cross section of the shell of Holospira elizabethae showing that the internal columella is hollow, which is typical feature of the genus.

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.[2]

The aperture is small, obliquely pear-shaped, rounded or oval. The peristome is expanded or reflected, continuous and usually free throughout.[2]

The columella (internal column) is hollow, variously sculptured or smooth.[2]

Anatomy

Drawing of Holospira elizabethae.

The foot is small, narrow for its length.[2]

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.[2]

The buccal mass is small, about twice as long as wide, the oesophagus opening well forward. Salivary glands are not united, in Holospira roemeri rather short, and on short ducts. In Holospira goldfussi the ducts are long.[2]

The jaw is thin, arcuate, with a wide median projection below or none.[2] 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).[2]

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.[2]

The free retractor muscles are excessively long, attached proximally to the axis at about the junction of the cone with the cylindrical portion of the shell. In Holospira roemeri the left ocular retractor unites with the pharyngeal retractor at about the posterior third of the length of the latter. This baud then unites with the colurnellar muscle near its posterior insertion. The right eye-retractor unites with the columellar muscle at about the anterior third of the length of the latter. Both ocular retractors give off some short anterior pedal branches distally. The pharyngeal retractor is not split at its distal insertion.[2]

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.[2]

Habitat

They are confined chiefly to the elevated plateau, where they live under cacti, etc., in sunny places.[2]

These snails can tolerate great heat.[2]

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.[2]

Species

Species in the genus Holospira include:[3][4]

References

This article incorporates public domain text from reference.[2]

  1. ↑ von Martens E. (1860). In: Albers, Helic., ed. 2: 39.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Pilsbry H. A. 1903. Manual of Conchology. Second series: Pulmonata. Volume 15 Urocoptidae. page 66-67.
  3. ↑ Holospira. ITIS. accessed 19 June 2009.
  4. ↑ Holospira. Discover Life, accessed 26 June 2009
  5. ↑ Gilbertson L. H. & Worthington R. D. 2003. A new species of Holospira (Pulmonata: Urocoptidae) from New Mexico. The Veliger, 46(3): 220-224.
  6. ↑ Gilbertson L. H. & Naranjo-García E. (2010). "A new species of Holospira (Gastropoda: Pulmonata: Urocoptidae) from Coahuila, Mexico". Nautilus 124: 181-184.
  7. ↑ Kathryn E. Perez. (last edited September 12, 2006) Land Snail List for Texas. accessed 25 June 2009.
  8. 1 2 Joseph H. Hartman. 1981. Early Tertiary nonmarine Mollusca of New Mexico: A review. GSA Bulletin, Geological Society of America, December 1981, 92(12): 942-950. doi:10.1130/0016-7606.

Further reading

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