Placostylus ambagiosus | |
---|---|
A shell of the subspecies Placostylus ambagiosus priscus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Gastropoda |
Subclass: | Heterobranchia |
Order: | Stylommatophora |
Family: | Bothriembryontidae |
Genus: | Placostylus |
Species: | P. ambagiosus
|
Binomial name | |
Placostylus ambagiosus |
Placostylus ambagiosus is a species of flax snail ( Māori: pūpū whakarongotaua [4]), a large air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Bothriembryontidae.
This snail has a large (43–97 millimetres or 1.7–3.8 inches long) [5] shell, which is heavily calcified. The size of the adult shell is habitat dependent, [5] but the shell shape is not plastic. [4] Placostylus ambagiosus is highly valued by Te Aupōuri me Ngāti Kurī (the indigenous people of northern New Zealand) as a food source, musical instrument and in the past this snail provided alarm calls at night warning of approaching invaders. [6]
This land snail species occurs in New Zealand. It is restricted to a small fragmented area of Northland Region, including the Aupouri Peninsula and Motuopao Island. [7] In the past local Māori moved and propagated populations of Placostylus ambagiosus, [8] [9] so today at least three extant populations are found on old pā sites (fortified settlements), along with other species that were cultivated such as karaka ( Corynocarpus laevigatus) and harakeke ( Phormium tenax). [10] [11]
This snail feeds at night on fallen leaves on the forest floor. [5] A favorite plant species is hangehange (Geniostoma ligustrifolium). Placostylus ambagiosus needs year round moisture provided by deep leaf-litter. Eggs are laid in clutches (average 43 eggs) in the shallow hollows in the soil. [5] The species is slow-growing with a lifespan of 10–22 years and strong site fidelity [12] The same individual snail has been found under the same food plant for 12 years. [5] The species is endangered due to predation from rats [13] and birds, [14] habitat damage by pigs and horses and competition from introduced snails. [13]
Based on molecular phylogeny (mtDNA) and shell morphology research it was suggested in 2011 by Buckley et al. [15] that there are no subspecies of Placostylus ambagiosus. [15] However, in the past, what were thought to be eight extant subspecies and a number of undescribed but distinct populations, were named; [7] six of these "subspecies" are now extinct [16] (marked with a †); conservation statuses were given according to the New Zealand Threat Classification System for the extant taxa: "nationally critical" and "nationally endangered": [17] At least five subspecies of Placostylus ambagiosus can be recognized using shell shape (not size or location) of individuals snails suggesting these represented distinct populations that require protection. [4]
Placostylus ambagiosus | |
---|---|
A shell of the subspecies Placostylus ambagiosus priscus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Gastropoda |
Subclass: | Heterobranchia |
Order: | Stylommatophora |
Family: | Bothriembryontidae |
Genus: | Placostylus |
Species: | P. ambagiosus
|
Binomial name | |
Placostylus ambagiosus |
Placostylus ambagiosus is a species of flax snail ( Māori: pūpū whakarongotaua [4]), a large air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Bothriembryontidae.
This snail has a large (43–97 millimetres or 1.7–3.8 inches long) [5] shell, which is heavily calcified. The size of the adult shell is habitat dependent, [5] but the shell shape is not plastic. [4] Placostylus ambagiosus is highly valued by Te Aupōuri me Ngāti Kurī (the indigenous people of northern New Zealand) as a food source, musical instrument and in the past this snail provided alarm calls at night warning of approaching invaders. [6]
This land snail species occurs in New Zealand. It is restricted to a small fragmented area of Northland Region, including the Aupouri Peninsula and Motuopao Island. [7] In the past local Māori moved and propagated populations of Placostylus ambagiosus, [8] [9] so today at least three extant populations are found on old pā sites (fortified settlements), along with other species that were cultivated such as karaka ( Corynocarpus laevigatus) and harakeke ( Phormium tenax). [10] [11]
This snail feeds at night on fallen leaves on the forest floor. [5] A favorite plant species is hangehange (Geniostoma ligustrifolium). Placostylus ambagiosus needs year round moisture provided by deep leaf-litter. Eggs are laid in clutches (average 43 eggs) in the shallow hollows in the soil. [5] The species is slow-growing with a lifespan of 10–22 years and strong site fidelity [12] The same individual snail has been found under the same food plant for 12 years. [5] The species is endangered due to predation from rats [13] and birds, [14] habitat damage by pigs and horses and competition from introduced snails. [13]
Based on molecular phylogeny (mtDNA) and shell morphology research it was suggested in 2011 by Buckley et al. [15] that there are no subspecies of Placostylus ambagiosus. [15] However, in the past, what were thought to be eight extant subspecies and a number of undescribed but distinct populations, were named; [7] six of these "subspecies" are now extinct [16] (marked with a †); conservation statuses were given according to the New Zealand Threat Classification System for the extant taxa: "nationally critical" and "nationally endangered": [17] At least five subspecies of Placostylus ambagiosus can be recognized using shell shape (not size or location) of individuals snails suggesting these represented distinct populations that require protection. [4]