Partula
Partula is a genus of land snails, constituting over 100 species of arboreal land snails native to French Polynesia and neighboring islands.
Their decline and extinction is the result of failed biological control. The giant African land snail was introduced to French Polynesia as a food source, which escaped and began destroying crops. The rosy wolfsnail was subsequently introduced to eat and eradicate the giant African land snail. It instead chose to eat the 100 species of Partula endemic to the islands, resulting in an accidental mass extinction event within French Polynesia.
Some species were successfully saved by scientists who collected the last live individuals from French Polynesia and took them into captivity for breeding. Others have been resilient enough to survive in the wild.
Notable species
[change | change source]Partula affinis, which survived in a valley the rosy wolfsnail never reached. It is believed to be a closely related species to Partula otaheitana.
Partula clara, which continues to survive in some areas.
Partula exigua, the first species of Partula to become extinct, a predatory snail itself which ate other native snails. These prey snails' populations increased after its extinction. It was named for being the smallest Partula species.
Partula faba, the first species of Partula to be described, which was taken into capitivity but failed to breed. The last died in 2016.
Partula hebe, which is a successfully bred species. The last 9 snails were collected and bred, and have been reintroduced to the wild over 20 years later.
Partula hyalina, which is an extremely resilient species. It continues to survive in the prescence of the rosy wolfsnail as well as on several islands the rosy wolfsnail was not introduced to.
Partula otaheitana, the second Partula species to be described, after Partula faba. Closely related to Partula affinis.
Partula rosea and Partula varia, two species native to Huahine. These two species were used by the natives to make jewelry. Both were successfully taken into captivity and released some time after.
Partula suturalis and Partula taeniata, previously considered extinct but now considered extant because of taxonomic changes. Initially they were each confined to one subspecies, P. s. suturalis and P. t. taeniata, both extinct, but since then other species have been demoted to subspecies under these two species, resulting in their "de-extinction".
Partula turgida, the first known extinction due to a parasite. Was taken into the breeding program but all snails were killed by a parasite that infested the breeding chamber.
Surviving species
[change | change source]This is a complete list of the surviving species.
Island | Species | IUCN | Status |
---|---|---|---|
Tahiti | Partula affinis | Critically Endangered | Reintroduction supported |
Partula clara | Critically Endangered | Relict | |
Partula hyalina | Vulnerable | Reintroduction supported | |
Partula nodosa | Extinct in the Wild | Reintroduced | |
Partula otaheitana | Critically Endangered | Relict | |
Moorea
(Mo'orea) |
Partula mirabilis | Extinct in the Wild | Reintroduced |
Partula mooreana | Extinct in the Wild | Reintroduced | |
Partula suturalis | Extinct in the Wild | Reintroduced | |
Partula taeniata | Critically Endangered | Reintroduction supported | |
Partula tohiveana | Extinct in the Wild | Reintroduced | |
Huahine | Partula rosea | Extinct in the Wild | Reintroduced |
Partula varia | Extinct in the Wild | Reintroduced | |
Raiatea | Partula garrettii | Extinct in the Wild | Reintroduced |
Partula hebe | Extinct in the Wild | Reintroduced | |
Partula navigatoria | Extinct in the Wild | Reintroduced |
Reintroductions
[change | change source]P. garrettii was misidentified as P. tristis for some time, and P. navigatoria was misidentified as P. dentifera.
Species | IUCN | 2015 | 2016 | 2017 | 2018 | 2019 | Total |
---|---|---|---|---|---|---|---|
Tahiti | |||||||
Partula affinis | CR | 48 | 201 | 129 | 240 | 182 | 800 |
Partula hyalina | VU | 1 | 8 | 90 | 71 | 12 | 182 |
Partula nodosa | EW | 220 | 877 | 1,777 | - | 2,528 | 5,402 |
Moorea | |||||||
Partula mirabilis | EW | - | - | - | 10 | 60 | 70 |
Partula mooreana | EW | - | 592 | 344 | - | - | 936 |
Partula suturalis strigosa | EW | - | - | - | - | - | 0 |
Partula suturalis vexillum | EW | - | 374 | 290 | 171 | 210 | 1,045 |
Partula taeniata nucleola | CR | - | 100 | 206 | 201 | 219 | 726 |
Partula taeniata simulans | CR | - | 67 | - | 549 | 360 | 976 |
Partula tohiveana | EW | - | 639 | 950 | 766 | 710 | 3,065 |
Huahine | |||||||
Partula rosea | EW | - | - | - | - | 1,896 | 1,896 |
Partula varia | EW | - | - | - | - | 522 | 522 |
Raiatea | |||||||
Partula garrettii | EW | - | 38 | - | - | - | 38 |
Partula hebe | EW | - | 81 | - | - | - | 81 |
Partula navigatoria | EW | - | 96 | - | - | - | 96 |
Species list
[change | change source]All species of Partula within the Society Islands are listed here, sorted by island:
- Partula affinis
- Partula clara
- Partula compressa
- Partula cytherea
- Partula diminuta
- Partula hyalina
- Partula incrassa
- Partula incrassa exigua
- Partula incrassa incrassa
- Partula jackieburchi
- Partula laevigata
- Partula nodosa
- Partula otaheitana
- Partula aurantia
- Partula mirabilis
- Partula mooreana
- Partula suturalis
- Partula suturalis strigosa
- Partula suturalis vexillum
- Partula taeniata
- Partula taeniata elongata
- Partula taeniata nucleola
- Partula taeniata simulans
- Partula tohiveana
- Partula arguta
- Partula rosea
- Partula varia
- Partula bilineata
- Partula eremita
- Partula planilabrum
- Partula sagitta
- Partula umbilicata
- Partula lutea