Miselaoma sinistra (Gabriel, 1930)

Miselaoma sinistra (Gabriel, 1930)

    Ferntree Gully (3752'S X 14517'E), Victoria, Australia, Museum Victoria (MV) F106192, digital image by Chris Rowley (MV), 2009. The above image is the property of the Museum Victoria, Melbourne, Australia and is used with permission of that entity (permission granted on April 30, 2010). Further use of this image is prohibited without express written consent of the museum.

    Top: Punctum pygmaeum (Draparnaud, 1801), Manchester Center, Bennington Co., Vermont; see  http://www.jaxshells.org/pdfs/vt10.pdf. Bottom: Miselaoma weldii (Tenison-Woods, 1877), The Nut, Stanley, Tasmania. Scale line = one mm.
    The genus Miselaoma Iredale, 1933, of which Helix weldii Tenison-Woods is the type, appears to be exclusively sinistral, a unique condition for its family. There is a third named species, Miselaoma reevesbyi Cotton, 1938 from Reevesby Is, Spencer Gulf, South Australia. Aussie snailer Kevin Bonham [in litt. 18 Feb., 2010] suspects a fourth, as yet un-named, species lurks in the forests of southern New South Wales.

    The three taxa illustrated above belong to the Punctidae Morse, 1864. According to Schileyko (2002) the family has two subfamilies: Laominae Suter, 1913 (Australia to New Zealand: about 23 genera containing about 122 species) and Punctinae with one genus, Punctum Morse, 1864, Holoarctic in distribution and containing about 25 species in four subgenera, the nominotypical one with at least 16 species, five of which occur in the USA, four of them treated elsewhere on the website:
P. blandianum Pilsbry, 1900
P. minutissimum (I. Lea, 1841) <http://www.jaxshells.org/minute.htm>, <http://www.jaxshells.org/69ej.htm>, <http://www.jaxshells.org/caverns1.htm>
P. randolphi (Dall, 1895) (see scanning electron micrograph (SEM) below); this specimen was collected from leaf litter on a mossy slope above the R bank of a Siuslaw R. tributary near Mapleton, Lane Co., Oregon by H. G. and R. H. Lee on 21 October, 2006.
P. vitreum H. B. Baker, 1930 <http://www.jaxshells.org/pdfs/vt10.pdf>
Also endemic to North America is monotypic P. (Pseudopunctum) Morrison, 1935, based on Punctum smithi Morrison, 1935.

    The widely-introduced Paralaoma servilis (Shuttleworth, 1852) [Punctidae: Laominae] has found its way to various points near the west coast of the USA (see SEM below). This specimen was collected from leaf litter near the right bank of Beaver Creek in a public park just W of US 101, Lane Co., Oregon by H. G. and R. H. Lee on 20 October, 2006.

Schileyko, A. A., 2002. Treatise on Recent terrestrial pulmonate molluscs 8. Punctidae, Helicodiscidae, Discidae, Cystopeltidae, Euconulidae, Trochomorphidae. Ruthenica supplement 2: (ii) + 1035-1166 incl. numerous text figs. Jan.

Punctum randolphi

Punctum servilis

    Scanning electron micrographs performed under the auspices of the Dept. of Invertebrates of the United States National Museum with the excellent technical assistance of Ms. Yolanda Villacampa.