Petalifera
Encyclopedia
Petalifera is a genus
of sea slug
s or sea hare
s, marine
gastropod mollusks belonging to the family
Aplysiidae
, the sea hares.
Some authors place this genus in a separate family Dolabriferidae. A new study, published in September 2004, has shown that the genus Petalifera is paraphyletic.
(Note: Gastropod taxonomy
has been in flux for more than half a century, and this is especially true currently, because of new research in molecular phylogeny. Because of all the on-going changes, different reliable sources can yield very different classifications.)
A more general description can be found on the page of the superfamily Aplysioidea.
cavity and the vestigial shell. These sea hares swim by coiling and uncoiling the body.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of sea slug
Slug
Slug is a common name that is normally applied to any gastropod mollusc that lacks a shell, has a very reduced shell, or has a small internal shell...
s or sea hare
Sea hare
The clade Aplysiomorpha, commonly known as Sea hares or Sea Bags , are medium-sized to very large Opisthobranchia with a soft internal shell made of protein...
s, marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
gastropod mollusks belonging to the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Aplysiidae
Aplysiidae
The superfamily Aplysioidea is a superfamily of mostly rather large sea slugs, marine gastropod mollusks in the clade Aplysiomorpha within the informal group Opisthobranchia.This superfamily contains only one family, the Aplysiidae; the sea hares...
, the sea hares.
Some authors place this genus in a separate family Dolabriferidae. A new study, published in September 2004, has shown that the genus Petalifera is paraphyletic.
(Note: Gastropod taxonomy
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
has been in flux for more than half a century, and this is especially true currently, because of new research in molecular phylogeny. Because of all the on-going changes, different reliable sources can yield very different classifications.)
A more general description can be found on the page of the superfamily Aplysioidea.
Description
The parapodia (fleshy winglike outgrowths), as can be seen in photos of Petalifera petalifera, are almost completely fused. The pair of small rounded flaps form the parapodial cavity over the mantleMantle (mollusc)
The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...
cavity and the vestigial shell. These sea hares swim by coiling and uncoiling the body.
Species
- Petalifera albomaculata Farran, 1905
- Petalifera habei Eales, 1960 (synonym of Petalifera ramosa)
- Petalifera krusadalai O’Donoghue, 1930
- Petalifera petalifera Rang, 1828
- Distribution : Cosmopolitan.
- Length : 2 to 4 cm
- Color : grayish to brown, with white longitudinal bands; almost translucent.
- Description : rather flat body; their color camouflages them when they are grazing on the brown alga Padina.
- Petalifera punctulata Tapparone-Canefri, 1874
- Distribution : JapanJapanJapan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
- Distribution : Japan
- Petalifera qingdaonensis Lin, 1990
- Petalifera ramosa Baba, 1959
- Distribution : Western Pacific, Atlantic.
- Length : 5 to 7 cm
- Color : pink to pale brownish, with white rings over the body; almost translucent.
- Description : mantle covered with firm conical tubercles; the larger tubercles have terminal papillae with retractable filamentous branches; difficult to find, mostly hidden under the leaves of green alga CaulerpaCaulerpaCaulerpa is a genus of seaweeds in the family Caulerpaceae . They are unusual because they consist of only one cell with many nuclei, making them among the biggest single cells in the world...
.