Paralaoma servilis

Paralaoma servilis (Shuttleworth, 1852)
Pin-head Spot

  • Helix (Helicella) pusilla Lowe 1831: 46, pl. 5, fig. 17, non Helix pusilla Vallot, 1801 nec Fleming, 1828.
  • Helix servilis Shuttleworth 1852: 140.
  • Helix caputspinulae Reeve 1852 (1851–1854): pl. 133, fig. 818.
  • Helix conspecta Bland 1865: 163, fig. 7.
  • Tonites [sic; Zonites] diegoensis Hemphill in W. G. Binney 1892: 168, pl. 3, fig. 2 (Coan & Roth 1987).
  • Punctum conspectum var. pasadenae Pilsbry 1896: 21.
  • Punctum conspectum alleni Pilsbry in Pilsbry & Ferriss 1919: 326.
  • Many additional synonyms and possible synonym in many parts of the world; see Gittenberger et al. (2020).
Paralaoma servilis
Paralaoma servilis, Riverside Park, Smithers, British Columbia; width 2.2 mm (RGF 97.207.2238).

Identification. Shell depressed heliciform. Spire moderately elevated, conical. Sutures deep. Whorls ca 4, rounded, convex. Protoconch smoothish or with spiral striae. Teleoconch with narrow, widely spaced colabral riblets, weaker on base; with usually 5 or 6 colabral striae between riblets; colabral striae beaded by spiral striae. Aperture rounded-lunate, wider than high, edentulous. Last whorl slightly descending above. Lip thin, simple. Umbilicus ca ¼ shell width. Shell yellowish or brownish olive. Shell width to 2.4 mm (wider than high).

Habitat. Often disturbed habitats such as roadsides and in parks and gardens, but some sites are surprisingly remote and less disturbed. In leaf litter, under dead wood, and under rocks. Most often seen alive in cool weather.

Global range. Unalaska Island, Aleutian Islands, Alaska (Eyerdam 1933), south into Mexico (Smith et al. 1990); in the USA, east to Idaho and Montana (Burke 2013). Elsewhere, the list of places where it has been found is long. Caribbean: Jamaica and Cuba; Asia: Russia (Kurile Islands and Sakhalin, Primorsky, southern Kamchatka), Tajikistan, possibly China, Azerbaijan, Turkey, Jordan, Israel, and Saudi Arabia; North Africa: Algeria and Morocco; Sub-Saharan Africa: Eritrea, Ethiopia, Kenya, Tanzania, Uganda, and possibly South Africa, Mozambique, Congo, and Malawi; Pacific Islands: Easter Island and possibly Hawaii; Atlantic Islands: Canaries, Cape Verdes, Azores, Madeira, and St Helena; Europe: UK and Scandinavia, south to the Iberian Peninsula, east to the Balkan Peninsula and Cypress (see Gittenberger et al. 2020 for more information and additional references).

The native range is rather questioned but generally it is thought to be native to New Zealand. However, Roth (1986) thought it native to North America, on account of the remoteness of some localities where it had been found.

Range in Canada. British Columbia: sporadic, over most of the province. Expected in the southern Yukon.

Etymology. Latin, servilis, “of a slave”.

Remarks. This species has been known by several different names in recent years, and th full list of synonyms or possible synonyms is long (see Gittenberger et al. 2020 and references therein). In the North American literature, the species was long known as Punctum conspectum. Pilsbry (1948), who knew the species as Punctum conspectum, recognized two subspecies in additional to the nominotypical subspecies: P. c. pasadenae (with the major riblets reduced or absent) and P. c. alleni (with the riblets larger and the spire rather higher than “typical” examples. Roth & Sadeghian (2003) included pasadenae as a synonym; it seems likely that alleni is as well.