General Information

GLOBAL DISTRIBUTION: NATIVE French Polynesia (Societies); EXOTIC EXOTIC Cook Islands COOK ISLANDS STATUS: Introduced - Recent, Naturalised; S.Group only (widespread); Land, lowlands - mountains; on foliage KEY FEATURES: Spiralled conical shell, to 8x5mm(ØxH). SHELL trochus-like with rounded apex; whorls acutely angled; pale to dark brown, ± pale spots; columella fold distinct; basal pit conical. ANIMAL pale yellowish-white; foot elongate, grooved on the sides; grey eye-tentacles long and slender; make very sticky mucous. REPRODUCTION give birth to live young (=viviparous).

Cook Islands Distribution

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Southern Group: Present    Makatea: Present
RR	MG	AT	MK	MT	AK	PL	TK	MN
++++	P	-	P	-	-	-

Northern Group:
TN	MH	RK	PK	NS	SW

Diastole conula (Pease, 1861)
SYNONYMS: Microcystis conula (Pease, 1861); Diastole (Diastole) conula; Helix conula; Nanina conula; Trochonanina conula

TAXONOMY: ANIMALIA; MOLLUSCA; GASTROPODA; PULMONATA; Stylommatophora; Sigmurethra; Aulacopoda; Limacacea; HELICARIONIDAE (=Zonitoids)

GENERAL NOTE: This species is native in the Societies, and described from Tahiti in 1861. On Rarotonga Garrett in 1865 and/or 1869 found it very abundant only on one coastal shrub despite searching elsewhere. By 2005 it was abundant throughout the mountains. From this it is concluded that it was introduced to Rarotonga around the mid-1800s from the Societies or Rurutu (Australs). Garrett did not find on Aitutaki, Mangaia or Atiu when he visited in 1865, but they have subsequently been found on Mangaia and Mauke.

Vouchers:
Rarotonga: ~200 specimens on a large shore shrub, not found elsewhere despite careful searching, in Garrett 1881, ID as Microcystis conula; specimens in BPBM (probably Garrett's), reported Baker 1935 as Diastole conula; specimens 2005/10, on foliage inland to Cloud Zone, Fred Brook, with ID as Microcystis conula. Mangaia: specimens BPBM reported Baker 1935 as Diastole conula. Mauke: specimens BPBM reported Baker 1935 as Diastole conula.

References:
None recorded.

Data Update History (information):
zTX, zB02, zupB05b, zM02, zD05b

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