- Other Geographic Terms
- island endemic
- Range elevation
- 600 to 1158 m
- 1968.50 to 3799.21 ft
- Range length
- 18.5 to 23.1 mm
- 0.73 to 0.91 in
- Average length
- 21.4 mm
- 0.84 in
- Mating System
- polygynandrous (promiscuous)
has a lengthy gestation period and gives birth to large, live young that mature late and have a low fecundity. Although reproductive maturity occurs after the maximum size is reached, reproductive maturity may be dependent on age, not size. Reported age at maturity varies, ranging from 3 to 6.9 years. Similarly, reports of fecundity vary, but rates as low as 0.4 offspring/adult/year have been observed, as well as rates as high as 7 offspring/adult/year.
Little information about reproductive behavior in Partulina, sister to Achatinellidae, are thought to self-fertilize, so may self-fertilize as well. Partulina redfieldii can reproduce even in long-term absence of mates. The mechanism of this form of reproduction is not clear, however. Possibilities include parthenogenesis and long-term sperm storage, in addition to self-fertilization.is known, but this species is hermaphroditic and thought to breed year-round. Some species of the genus
Genetic evidence suggests interchiral mating takes place for (Hadfield and Mountain, 1980; Hadfield, 1986; Hadfield, et al., 1993; Holland and Hadfield, 2007; Killian, 2007; Kobayashi and Hadfield, 1996; Schilthuizen and Davison, 2005). Other terrestrial gastropods with high-spired shells like align themselves parallel and mount the other snail’s shell when mating. One snail inserts its penis in to the other and releases spermatophores. Embryos are intrauterine, and no more than two large embryos are contained in the uterus; usually there is only one. The large size of newborn , approximately 4.5 mm in length, limits the size of the maternal snail.
- Key Reproductive Features
- year-round breeding
- simultaneous hermaphrodite
- Breeding season
- breeds year-round.
- Range number of offspring
- <1 per year to 7 per year
- Range age at sexual or reproductive maturity (female)
- 3 to 6.9 years
Although the literature does not include specific information about parental investment in (Baur, 1994), in general, terrestrial gastropods do not provide parental care after birth. The most common form of parental investment for terrestrial gastropods comes in the form of calcium carbonate and other nutrients given to the developing egg.
- Parental Investment
- Typical lifespan
- 20 (high) years
- Typical lifespan
- Average lifespan
- 10 years
- Average lifespan
The home range ofis often limited to a single tree and the nearby surrounding shrubbery. Individuals rarely move between trees.
Communication and Perception
, like most terrestrial gastropods, communicates through both touch and chemical signaling, using the lower set of head tentacles. Individuals transmit pheromone signals both through direct contact and through the mucous trail left during locomotion. This includes warning of predator presence.
- Other Communication Modes
- Primary Diet
- Other Foods
The primary predator of Euglandina rosea, and has no defense mechanisms for this species. Several rat species eat , particularly the larger individual snails. Other foreign species that prey upon include the terrestrial flatworms Geoplana septemlineata and Platydemis manokwari. The Hawaiian Thrush (Phaerornis obscura) eats , although it isn't the bird's primary food source. (Hadfield, et al., 1993; Hart, 1978; Killian, 2007)is the introduced carnivorous snail,
Economic Importance for Humans: Positive
Economic Importance for Humans: Negative
There are no known negative effects ofon humans.
is the currently the most abundant species of the O’ahu tree snails and has been studied considerably for conservation efforts. The slow growth, long pre-reproductive life, and low fertility of , in conjunction with its relatively sedentary lifestyle and small geographic range, make populations very vulnerable to disturbances, either from predation, human collection, or habitat destruction. Lowland habitat destruction by human inhabitants for the purposes of farming and logging have reduced the geographic range of to only high elevation mountainous forests.
However, the introduction of the invasive predatory snail Euglandina rosea from North America led to the rapid and widespread decline and destruction of populations. Euglandina rosea predates opportunistically on a number of species of terrestrial snails. Only a few hundred individuals of are estimated to remain in the wild. (Hadfield, 1986; Hadfield, et al., 1993)
Peter Bicescu (author), The College of New Jersey, Colleen Stalter (author), The College of New Jersey, Keith Pecor (editor), The College of New Jersey, Renee Mulcrone (editor), Special Projects.
Referring to an animal that lives in trees; tree-climbing.
- bilateral symmetry
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
- internal fertilization
fertilization takes place within the female's body
- island endemic
animals that live only on an island or set of islands.
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
an animal that mainly eats fungus
- native range
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
- oceanic islands
islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.
reproduction in which eggs develop within the maternal body without additional nourishment from the parent and hatch within the parent or immediately after laying.
chemicals released into air or water that are detected by and responded to by other animals of the same species
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
mature spermatozoa are stored by females following copulation. Male sperm storage also occurs, as sperm are retained in the male epididymes (in mammals) for a period that can, in some cases, extend over several weeks or more, but here we use the term to refer only to sperm storage by females.
uses touch to communicate
Living on the ground.
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
- year-round breeding
breeding takes place throughout the year
Makua Military Reservation. Final Implementation Plan for Makua Military Reservation, Island of Oahu. Schofield Barracks, HI: United States Army Garrison, Hawaii Directorate of Public Works Environmental Division. 2003. Accessed January 03, 2013 at http://manoa.hawaii.edu/hpicesu/DPW/2003_MIP/Sec_1/2003_MIP_edited.pdf.
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