- Other Habitat Features
- intertidal or littoral
- Range depth
- intertidal to 20 m
- to 65.62 ft
- Development - Life Cycle
In laboratory conditions, (Stancyk, 1979)has a single reproductive period characterized by repeated spawning. Their first spawn takes place when they are roughly two months old and continues every two to four days until the end of their reproductive cycle roughly seven months later. They continue to feed and grow until they reach a maximum size. At this time they have also reached their peak spawn production. Throughout their seven month reproductive period each adult can produce an estimated 67 million eggs.
- Mating System
- polygynandrous (promiscuous)
Like all species of Aplysia, is hermaphroditic. The male genital opening lies just below the base of the right anterior tentacle, positioned between the right eye and the right side of the mouth. A strongly defined ciliated groove extends dorsally backward from male genetalia between the parapodia to the hermaphroditic orifice, which is marked by a dark depression. The groove is marked by a narrow black line stretching from the male genital opening to the hermaphroditic duct. When mating, one , acting as a male will climb partially onto a second , acting as a female, insert the male genetalia and releasing sperm into the hermaphroditic duct of the second. In this manner they form chains of up to 12 organisms, each acting as male and female simultaneously, the first in the chain acting only as a female, and the last acting only as a male. (MacFarland, 1909)
- Key Reproductive Features
- year-round breeding
- simultaneous hermaphrodite
- Breeding season
- 7 months
- Average number of offspring
- Average age at sexual or reproductive maturity (female)
- 2 months
- Average age at sexual or reproductive maturity (male)
- 2 months
These animals invest very little in each offspring. Individual eggs receive relatively little yolk, and there is no investment in offspring once the fertilized eggs are laid.
- Parental Investment
Following their peak spawn and maximum size (Stancyk, 1979)begins to lose weight and spawning declines, death soon follows.
- Average lifespan
- 10 to 11 months
- Average lifespan
In the adult stage,is a nocturnal organism, and moves about only after dark. This locomotion can be in two forms, swimming in the water column and crawling on the substrate. Swimming is achieved by folding the parapodia forward and down to create a funnel that pulls in water, pressing the anterior parts of the parapodia together forces the water out behind the animal and it is propelled forward. The more common crawling motion is known as contractive wave motion and is achieved by raising the leading edge of the foot and stretching it forward in an arching pattern; the rest of its body follows the arching pattern until it reaches the tail.
feeds on red and green algae. It uses its jaws to grasp the algae and its radula to pull the algae into its buccal cavity. The crop in is lined with chitinous plates and acts like a gizzard to aide in the digestion of the larger seaweeds that it eats.
- Primary Diet
- Plant Foods
When feeling threatenedwill elicit a quick downward movement of its parapodia over its back. It may also release foul fluids from both the opaline gland and the purple dye cavity.
- Known Predators
- large green sea anenomes (Anthopleura xanthogrammica)
- giant starfish (Coscinasterias calamaria)
This species is one of many that graze on algae in shallow warm water.
Economic Importance for Humans: Positive
- Positive Impacts
- research and education
This species is fairly abundant and not believed to need any special conservation efforts.
Renee Sherman Mulcrone (editor).
Melissa Emore (author), Hood College, Maureen Foley (editor), Hood College.
- Atlantic Ocean
the body of water between Africa, Europe, the southern ocean (above 60 degrees south latitude), and the western hemisphere. It is the second largest ocean in the world after the Pacific Ocean.
- Pacific Ocean
body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.
- 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.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
union of egg and spermatozoan
An animal that eats mainly plants or parts of plants.
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
- intertidal or littoral
the area of shoreline influenced mainly by the tides, between the highest and lowest reaches of the tide. An aquatic habitat.
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
having the capacity to move from one place to another.
- native range
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
specialized for leaping or bounding locomotion; jumps or hops.
- saltwater or marine
mainly lives in oceans, seas, or other bodies of salt water.
remains in the same area
offspring are all produced in a single group (litter, clutch, etc.), after which the parent usually dies. Semelparous organisms often only live through a single season/year (or other periodic change in conditions) but may live for many seasons. In both cases reproduction occurs as a single investment of energy in offspring, with no future chance for investment in reproduction.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- year-round breeding
breeding takes place throughout the year
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