INTRODUCED LAND SNAILS OF THE FIJI ISLANDS

Quantula striata Current Risk Status in Fiji: (Grey, 1834) Low FAMILY ARIOPHANTIDAE Body Type: Snail with well developed shell

Size: Description & Distribution Shell height ~ 15-20 mm, shell diameter ~ 26 mm Description USP Introduced Land Living striata (Gray, Snails of the Fiji 1834) are variable in body colour Islands Fact Sheet but generally reddish brown, pale Series, No. 7 grey or cream. The relatively thick, well-developed shell report- edly grows to 50 mm in diameter in some countries but this has not been observed in Fiji. The shell is dextral (right handed coiling) with a broadly rounded apex (= heli- P. Ryan coid). The shell is relatively large, Source and location of photographs: round and wide with six whorls. In P. Ryan,V. Chandra & G. Brodie (Fiji) colour the shell is generally deep reddish brown with a creamy white underside. A clear but nar- 1913 (Barker et al. 2005) and now row umbilicus (central opening) widely distributed in Fiji. Found in can be seen on the ventral surface. lowland to mid-elevation forests Dead shells are usually bleached and gardens. Also introduced in to pale brown or a dirty white. Singapore, Malaysia, Cambodia, the Philippines and some islands in Direct funding from the Critical Distribution the Rhio Archipelago. Quantula stri- Ecosystem Partnership Fund Native to the southern Malay Pen- ata is sometimes given the common (CEPF) and a USP FSTE Grant is gratefully acknowledged. insula. Established in Fiji prior to name “Bioluminescent Snail”.

Special points of Habitat & Behaviour interest:

• Quantula striata is reportedly the only land snail in the world capa- Habitat Behaviour ble of true bioluminescence. Quantula striata is generally found Quantula striata prefers cool damp on the ground but can also climb areas with shady vegetation. It is • Quantula striata is considered a on low vegetation. Found pre- gregarious in nature and can there- comparatively low risk introduced land snail in Fiji because dominantly in human-disturbed fore often be found together with it has not been observed as a areas such as disturbed forests, other individuals, particularly when crop pest or a disease vector and inactive during the hotter and drier is generally found only in dis- gardens, waste ground, lawns, turbed areas. rubbish dumps, under concrete times of the day. Quantula striata is and in open shrubland. It is gen- an omnivore (feeds on both plants • Quantula striata is common on erally found all year around, but is and ) however it appears to USP’s Laucala campus and in the Sigatoka Sand Dunes Park. It is especially abundant during the prefer decaying flesh. More re- generally only active at night or wet seasons (Isobe et al. 1991). search is needed to confirm this. during cool wet weather. Page 2 Quantula striata (Gray, 1834)

FIJI LAND SNAILS P. Ryan V. Chandra Biology

Quantula striata is regarded as the only land (Isobe et al. 1991). The biological function of the gastropod in the world capable of true biolu- bioluminescence in Q. striata has not been well minescence (Councilman & Ong 1988). There established. To the best of our knowledge this is a special organ inside the head which cre- phenomena has not been recorded in Fiji. Quan- ates flashes of yellow-green light (Copeland tula striata reportedly reaches reproductive ma- et al. 1987) although the bioluminescence is turity at about 16mm in shell diameter reportedly found only in eggs and juveniles (Councilman et al. 1988). Threats & Similar Species

Threats similar shell shape but is smaller and generally Quantula striata evidently poses no immediate paler in shell colour when the is alive. The threat but it is a relatively large snail that can comparative adult shell size of B. similaris is shell occur in high numbers, so it is likely to com- diameter ~14mm, shell height ~11mm. The umbili- pete with native species at the very least. cus of Q. striata (seen as a small hole centrally in More research is needed. the shell’s ventral surface) is also narrower than in Similar Species B. similaris. Q. striata is often assigned to the ge- Bradybaena similaris (Rang, 1831) has a very nus Dyakia. Further Reading

Barker, G.M., Price, R. & Briggs, C. (2005). Pri- Tan W.H. & Maneri, M. (1987). Factors affect- orities for additions to the Fijian protected ing the rate of flashing and loss of lumines- natural areas network: an assessment based cence in an Asian land snail Dyakia striata. The on complementarity in land snail assem- Veliger, 29:394-439. blages. New Zealand Landcare Research Councilman, J. & Ong, P. (1988). Responses of the contract report prepared for Wildlife Con- luminescent land snail Dyakia (Quantula) stri- servation Society, Suva. 162 pp. ata to natural and artificial lights. Journal of Brodie, G., Mila, E., Sheehy, A. & Singh, R.R. Ethology, 6:1-8. (2010). A Preliminary Survey of the Land Gray, J.E. (1834). Characters of new species of Snail Fauna of the Sigatoka Sand Dune Na- shells. Proceedings of the Zoological Society of tional Park, Sigatoka, Fiji. Report to Fiji Na- London 1834:57-72. [p.59, original description tional Trust. 14 pp. as Nanina striata]. Copeland, J. & Daston, M.M. (1989). Biolumi- Isobe M., Yuakul D., Sigurdsson J.B., Goto T. & nescence in the terrestrial snail Quantula Lam T. J. (1991). Fluorescent substance in the (Dyakia) striata. Malacologia, 30:317-324. luminous land snail, Dyakia striata. Agricultural Copeland, J., Counsilman J.J., Loh D., Chan S.Y., and Biological Chemistry, 55:1947-1951.

How to Cite: For Further Information Contact: Brodie, G. & Barker, G.M. 2012. Quantula striata Dr Gilianne Brodie, Biology Division, USP, (Gray, 1834). Family Ariophantidae. 'USP Introduced Suva, Fiji Islands. Phone: 679 3232876, Land Snails of the Fiji Islands Fact Sheet Series’, No. 7. Email: [email protected]