Theba pisana ( Müller, 1774 )

Blacket, Mark J., Shea, Michael, Semeraro, Linda & Malipatil, Mallik B., 2016, Introduced Helicidae Garden Snails in Australia: Morphological and Molecular Diagnostics, Species Distributions and Systematics, Records of the Australian Museum 68 (3), pp. 99-116 : 114

Theba pisana ( Müller, 1774)

Objective synonym— Helix pisana .

Common names—White Garden Snail, White Gardensnail, White Italian Snail.

Material examined. New South Wales: AM C088901 Nelson Bay, Port Stephens; AM C206180 Redhead Beach, Newcastle; AM C168582 Avalon Beach, Sydney; AM C407047 Waniora Point, Bulli; AM C348456 Cunjurong Point, E of Lake Conjola; AM C404152 Cudmirrah Beach near Sussex Inlet; AM C334544 Aslings Beach, Twofold Bay, Eden. Victoria: Venus Bay VAITC 3831–3837, VAIC ×10; Port Campbell VAIC ×3, 3 km North Port Campbell VAIC ×3.

Diagnosis. Shell: small (up to 2 cm), thick to thin, tall and narrow, raised spire, subglobose, 5 whorls, body-whorl moderately flared, aperture medium and rounded, narrow umbilicus, shell lip thickened pink internally only and not reflected out in adults, whorls rounded in adults angulate in juveniles. Shell colour: white usually with broken thin dark brown spiral bands and chevrons. Soft body: pale overall. Adults: identified by the presence of rounded body-whorls ( Stanisic et al., 2010).

Distribution in Australia. Present in southern Australia: NSW, Tas., Vic., SA, WA.

Remarks. The species identification of VAITC specimens (above) was confirmed in the present study through DNA barcoding (ITS2 and COI) and comparison with validated AM specimens. The genus Theba contains at least 18 species in its natural range ( Greve et al., 2010), but only Theba pisana pisana occurs worldwide (e.g., Cowie et al., 2009; Greve et al., 2010; Däumer et al., 2012). Australian specimens belong to T. p. pisana ( Däumer et al., 2012; current study). CABI species datasheet: http://www.cabi. org/isc/datasheet/62094.

AUTHOR CONTRIBUTION STATEMENT. All authors were involved in the conception and design of this research, identifying diagnostic specimens during the initial eastern Australian detection of Green Garden Snails, and contributing to the systematics section. MB conducted the morphometric and molecular experimental work, and produced the specimen images (apart from Figs 2 and 4 ). MS provided expert support through validating identifications of reference specimens, providing unpublished background information and assisting with the morphometrics section. All authors collected snails for this study and contributed to the writing of the manuscript.

ACKNOWLEDGMENTS. This work was funded by the Victorian Department of Primary Industries (DEDJTR, formerly DEPI). We would like to thank Gordon Berg, Sharon Dorsett & Emily Crawford (Biosecurity DEDJTR) for field information; Gordon Berg, Andrew Henderson, Jane Moran, Harry Cleaver and David Madge (DEDJTR) for collecting specimens, advice and assistance; Gordon Berg, Andrew Henderson for live snail images. Helicidae specimen records were checked on the APPD (Australian Plant Pest Database) and the ALA ( Atlas of Living Australia), as well on specific museum databases: Australian Museum, Sydney (Michael Shea), Museum Victoria, Melbourne (Adnan Moussalli), Tasmanian Museum and Art Gallery, Hobart (Simon Grove), Queen Victoria Museum and Art Gallery, Launceston (Robert Mesibov). We thank Luke Watson (Department of Agriculture and Water Resources) for information on Helicidae border interceptions and for permission to include records from the OSP Bulletins ( Table 3). We thank the Australian Museum for specimen loans, for allowing images to be taken of E. vermiculata , as well as for the images produced by Des Beechey for Fig. 4 . We also thank Alan Yen (DEDJTR) for use of photographic equipment for imaging shell specimens, Michael Nash (SARDI) for suggestions, advise and providing access to an unpublished SARDI survey report, and the Western Australian Museum (Terry Houston) for donation of two Western Australian C. apertus specimens to the VAIC. Finally, we thank the RAM journal editors, Shane McEvey and Don Colgan and anonymous reviewers for providing useful suggestions and corrections that improved this manuscript.

Figures

Figure 2. Images of live Brown (C. aspersum) and Green (C. apertus) Garden Snails. (A) Brown adult, Knoxfield Vic.; (B) Green adult, Cobram Vic.; (C) Brown adult, Knoxfield Vic. (left) and Green adult, Cobram Vic. (right); (D) Brown juvenile, Knoxfield (left ×1) and Cobram (right ×2) [note: these three specimen identifications (VAITC 3071–3073) were confirmed through DNA barcoding in the present study]; (E) Green Juvenile, Cobram Vic.; (F) Green epiphragm, Cobram Vic. Image credits: A–E, Andrew Henderson (DEDJTR); F, Gordon Berg (DEDJTR).

Figure 4. Some exotic species of Helicidae commonly misidentified and/or intercepted at the Australian border. (A) Helix pomatia (AM C22156), SW=30–50 mm;(B) Cepaea nemoralis (AM C166354), SW=18–25 mm; (C) Arianta arbustrorum (AM unregistered England), SW = 18–25 mm; (D) Otala lactea (AM unregistered, Portugal), SW = 30–40 mm. (Images are adults, not shown to same scale). Image credits: A–D, Des Beechey (AM).