Flabellina goddardi

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Flabellina goddardi
Flabellina goddardi

Flabellina goddardi

Systematics
Order : Hind gill snails (Opisthobranchia)
Subordination : Nudibranchia (Nudibranchia)
Superfamily : Thread snails (Aeolidioidea)
Family : Flabellinidae
Genre : Flabellina
Type : Flabellina goddardi
Scientific name
Flabellina goddardi
Terrence Gosliner , 2010

Flabellina goddardi is a sea ​​snail and belongs to the nudibranch , the largest suborder of the hind-gill snail .

features

So far, more than 50 species of the genus Flabellina have been described, among marine biologists the particularly colorful Flabellina iodinea is known. Outwardly, Flabellina goddardi is most similar to Flabellina pricei (MacFarland, 1966) and Flabellina pellucida (Alder & Hancock, 1843). All three types have cerata , which are long processes that are arranged in several rows on the back and sit on raised pedestals. However, both Flabellina pricei and Flabellina pellucida have lateral rows of teeth on the radula , while these are absent in Flabellina goddardi .

The living animal is relatively small. When fully grown, it reaches a length of about 30 mm. The body is translucent white with salmon colored digestive glands within the cerata. The lateral skin processes are elongated, slightly pointed and have a circular cross-section with a slightly thinner base. They are glossy yellow-orange with a purple-orange band below their tip. The color pattern of Flabellina goddardi is unique compared to all other members of the genus Flabellina . There is no pigmentation on the head, on the body or on the tentacles . The cerata are arranged in different groups. There are four rows of cerata in the front area, in front of the heart, with four to nine cerata per row. The cerata behind the heart are divided into seven different rows, with one to ten cerata per row.

The front end of the head is slightly notched. The rhinophores on the head are smooth. Only two of the 15 related species on the west coast of the North American continent also have this characteristic: Flabellina amabilis and Flabellina bertschi . The rhinophores are about 2/3 the length of the mouth tentacles. These tentacles are narrow, elongated, and taper to a thin point. They are important for the snail's sensory perception.

The buccal apparatus is thick and muscular with a pair of brown, leathery jaws. Each of these jaws has a single row of around twelve triangular denticles that can be seen under a light microscope . The gonopore is located on the right half of the body, ventral to the third and fourth row of cerata. It is encompassed by a large, fleshy genital lobe.

Kleptocnids

The species Flabellina goddardi has kleptocnids on its back. As with other species of the genus Flabellina , these stinging cells are probably used as protection against predators . The nettle cells are not formed by the snail itself, but come from the hydrozoa on which Flabellina goddardi feeds. They then migrate into the epidermis at the tips of the snail's cerata. The striking orange tips of the salmon-colored cerata from Flabellina goddardi could be a warning signal to the predators.

Reproductive organs

Flabellina goddardi is a hermaphrodite species that forms both male and female germ cells .

The reproductive organ consists of an elongated, thin canal that spreads out into a curved ampoule. This in turn divides into a short, narrow fallopian tube and the wider spermatic duct . At this connection point, the large bag of seeds, Receptaculum seminis , is attached to an elongated tube. The fallopian tube runs into the female gland, which consists of a small albumin gland, a lobed membrane gland, and a larger, smooth, slimy gland. In addition to the fallopian tube, Flabellina goddardi also contains a copulatrix bursa . The bursa runs over a wide channel that opens into a small cave. The prostate part of the vas deferens is wide and consists of a single, solid body shaped like a curved cylinder. The narrow, short ejaculation part, which extends the penis, ends at the end of the segment of the prostate located towards the trunk. The wart-shaped elevation of the penis is conical in shape. In addition to the genital sac, there is also a genital gland, which is divided into two at the end.

Radula

The radula is rhachigloss with the formula: 30 × 0.1.0. The radula teeth are broad with a wide central point that is longer than the adjacent teeth. There are 7–8 elongated lateral teeth on each side of the central apex. Flabellina goddardi is the only Flabellina species that does not have rows of teeth on the side.

distribution

A wide variety of nudibranch snails live off the Pacific coast of North America, including 15 species of the genus Flabellina . Several species of the genus sympatric colonize the tidal basins off the coast of California . The first living specimen of Flabellina goddardi was found in such a tide pool on Carpinteria Reef off Carpinteria State Park in Santa Barbara County .

Way of life

Flabellina goddardi feeds mainly on hydroids.

Egg laying was observed in an aquarium. The species produces a long egg cord made up of thousands of strung together egg capsules. This egg cord is laid out on the floor in the form of a round latticework, reminiscent of a lace ceiling. The marine biologist Dr. Jeffrey Goddard considers the production of this complex network to be an adaptation in order to supply all embryos with sufficient oxygen. In the tidal pools where this snail lives, there may be a lack of oxygen during the day due to warming. Due to the small number of observations, it cannot currently be said whether the circular shape of the egg-laying is also part of the established behavior of Flabellina goddardi in nature .

Type 1 veliger larvae with a simple, twisted shell that is reminiscent of the housing of a nautilus and is later lost again emerge from the egg capsules . The larvae develop as part of the plankton .

Taxonomy

Discovery and naming

The nudibranch species was discovered in 2008 by the biologist Dr. Jeffrey Goddard of the University of California, Santa Barbara in a tide pool off Carpinteria , California. Dr. Terrence Gosliner described it in 2010 and named the sea snail after its discoverer Goddard, hence the name Flabellina goddardi .

A preliminary, molecular-genetic based phylogeny, which is based on an investigation of the H3 nuclear gene , COI and the 16S mitochondrial gene , is fundamental for the strain of the Flabellina species, including Flabellina goddardi .

Systematics

The California coast's nudibranchia fauna is particularly diverse. Behrens and Hermosillo (2005) listed 122 species of nudibranchias in California, including two previously undescribed species. Gosliner (1996) also documented two new species of nudibranch in deeper waters off the coast of southern California. Two additional species have recently been collected off the coast of California. The first taxon , a new species of Okenia, was found 37–40 m from Carmel, California. The species of the Eastern Pacific Okenia have recently been verified. Nine species are known to range from British Columbia to Costa Rica. Millen and Hermosillo (2007) examined the fifteen species of the genus Flabellina from the eastern Pacific. A new species of the genus Flabellina from the inter-tidal zone off Carpinteria, California, which clearly differs from all other members of the Flabellinidae, has recently been discovered.

Individual evidence

  1. ^ FM MacFarland, OH MacFarland: Studies of opisthobranchiate mollusks of the Pacific coast of North America  (= 6). California Academy of Sciences, 1966, ISBN 0940228106 .
  2. ^ J. Alder, Hancock A .: Notice on a British species of Calliopaea d'Orpigny, and on four new species of Eolis with observations on the development and structure of the nudibranchiate Mollusca. . In: Annals and Magazines of Natural History . 12, 1843, pp. 233-238.
  3. ↑ a b Fiery Sea Slug Discovered, Lays Lacy Egg Case article and photos by Flabellina goddardi at National Geographic on September 23, 2010
  4. ^ TE Thompson: The importance of the larval shell in the classification of the Saccoglossa and the Acoela . Proceedings of the Malacological Society of London, 34, 5, pp. 233-238, 1961
  5. ↑ Sea Slug Eggs Photos of the egg capsules and Veliger larvae of Flabellina goddardi at National Geographic on September 23, 2010
  6. ↑ Terrence M. Gosliner: Two new species of nudibranch molluscs from the coast of California . In: Proceedings of the California Academy of Sciences . Fourth Series, 61, No. 16, 2010, pp. 623-631. ( PDF )
  7. ↑ David W. Behrens, A. Hermosillo: Eastern Pacific Nudibranchs - a Guide to the Opisthobranchs from Alaska to Central America . Sea Challengers, Monterey, CA, 2005, ISBN 0930118367 , pp. 137pp.
  8. ^ A b Terrence M. Gosliner: The Opisthobranchia . In: Taxonomic Atlas of the Santa Maria Basin and Western Santa Barbara Channel, Mollusca, Part 2 . 9, 1996, pp. 1-52.
  9. ↑ Yolanda E. Camacho-García, Terrence M. Gosliner: A new species of Okenia (Gastropoda: Nudibranchia: Goniodorididae) from the Pacific coast of Costa Rica . In: Proceedings of the California Academy of Sciences . 55, No. 23, 2004, pp. 431-438. ( PDF )
  10. ↑ Terrence M. Gosliner and Hans W. Bertsch: Systematics of Okenia from the Pacific Coast of North America (Nudibranchia: Goniodorididae) with Descriptions of Three New Species . In: Proceedings of the California Academy of Sciences . 55, No. 22, 2004, pp. 414-430. ( PDF )
  11. ↑ Sandra Millen, Alicia Hermosillo: The genus Flabellina Voight, 1834 (Mollusca: Opisthobranchia) from Bahía de Banderas (Pacific Coast of Mexico) with ecological observations, the description of a new species, and the redescription of Flabellina cynara . In: Proceedings of the California Academy of Sciences . Fourth Series, 58, No. 26, 2007, pp. 543-556. ( PDF )

literature

  • Terrence M. Gosliner: Two new species of nudibranch molluscs from the coast of California . In: Proceedings of the California Academy of Sciences . Fourth Series, 61, No. 16, 2010, pp. 623-631. (Initial description, PDF )
  • David W. Behrens: Pacific Coast Nudibranchs: A Guide to the Opisthobranchs Alaska to Baja California , 2 Sub. Edition, Backhuys Publishers, April 1992, ISBN 0930118170 .

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