Julia exquisita

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Julia exquisita
Julia exquisita.jpg
Julia exquisita
Scientific classification
Kingdom:
Phylum:
Class:
Order:
(unranked):
clade Heterobranchia

Informal group Opisthobranchia
clade Sacoglossa

clade Oxynoacea
Superfamily:
Family:
Genus:
Species:
J. exquisita
Binomial name
Julia exquisita
Gould, 1862 [1]

Julia exquisita is a small species of sea snail with a green bivalve shell. It is a marine gastropod mollusk in the family Juliidae. [2]

Contents

This species can be found in shallow tropical habitats throughout the Pacific, and are known for their feeding of algae, in which photosynthetic cells are taken up and incorporated into the snails' body tissues for energy storage.

Distribution

Julia exquisita is a benthic organism, often residing in intertidal flats. [3] Individuals typically live at depths of about 3 meters, but have been observed at depths as low as 10 meters. [4]

Julia exquisita prefers a warmer climate with available sunlight, meaning that their distribution is relegated to tropical Pacific waters. The species has the greatest observed abundance in the coral triangle, along the coasts of Hawaii, and in the Caribbean, [5] but have also been found along the coast of Madagascar, Australia, and other Indo-West Pacific islands. [6]

Description

Individuals of Julia exquisita are dark green in color with a long thin body and a characteristic bivalve shell. They range from 4mm-6mm in length, with a dorsal foot roughly as wide as their neck. [3] The anterior edge of the grooved foot extends to a round oral tentacle used for feeding. Many individuals exhibit small white patches on their body which are often surrounded by brown rings. [3]

White eye prominences lead to thin, squared rhinophores extending from the head which act as scent and taste receptors. Within the oral feeding tentacle is a radula, or sharp tooth, which is used to feed by scraping their food source. [3]

The shell is the best defining characteristic of this species, as it is a two-parted convex dorsal shell which greatly resembles that of bivalves. [7] The shell is bright green in color, typically with red-brown or white bands surrounding its concentric lines. Shells have a round anterior margin and are ovular in shape. [3]

The internal anatomy of Julia exquisita is similar to that of other bivalve gastropods, with 2 shell valves surrounding a visceral mass containing their vital organs. Key anatomical differences between Julia exquisita and other similar species include proportionally larger adductor muscles, which are used to shut the two shell valves, as well as a slightly more complex penis. [3]

Reproduction and Development

Adult members of the species reproduce using internal fertilization in which male sperm fertilize female eggs which are laid and left to develop into larvae. While in ovum development, Julia Exquisita experiences a trochophore stage before assuming their final larval form. [7] Larvae take on a planktonic form after hatching, [5] and eventually use mucous threads to settle on algae covered surfaces. Once settled, larvae undergo metamorphosis until they reach their adult life stage. [8] Their characteristic bivalve shell is fully produced in about three days. [7]

Feeding and Behavior

Julia exquisita are opportunistic grazers. [5] Like other similar species, individuals use their sharp radula to pierce the cells of algae and suck out the cellular contents. These contents are then digested using mucous within the digestive tract. [4]

Their feeding habits also influence their behavior, as individuals typically tether themselves to algal colonies using mucous-like threads extending from their dorsal foot. Individuals can withdraw into their shell while still being tethered, allowing them to protect themselves from predation while staying attached to their food source. [7]

Like other members of the Juliidae family, Julia exquisita performs kleptoplasty in which functional contents of the algal cells are incorporated into their bodies. Specifically, chloroplasts from the algae are kept photosynthetically functional within the digestive gland. [4] This allows Julia exquisita to continue to use the energy produced through algal photosynthesis, while also contributing to the green color characteristic of this species.

Related Research Articles

The radula is an anatomical structure used by mollusks for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus. The radula is unique to the molluscs, and is found in every class of mollusc except the bivalves, which instead use cilia, waving filaments that bring minute organisms to the mouth.

Sacoglossa Clade of gastropods

Sacoglossa, commonly known as the sacoglossans or the "solar-powered sea slugs", are a superorder of small sea slugs and sea snails, marine gastropod mollusks that belong to the clade Heterobranchia. Sacoglossans live by ingesting the cellular contents of algae, hence they are sometimes called "sap-sucking sea slugs".

Sea snail Common name for snails that normally live in saltwater

Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible shell.

<i>Elysia chlorotica</i> Species of gastropod

Elysia chlorotica is a small-to-medium-sized species of green sea slug, a marine opisthobranch gastropod mollusc. This sea slug superficially resembles a nudibranch, yet it does not belong to that clade. Instead it is a member of the clade Sacoglossa, the sap-sucking sea slugs. Some members of this group use chloroplasts from the algae they eat for photosynthesis, a phenomenon known as kleptoplasty. Elysia chlorotica is one species of such "solar-powered sea slugs". It lives in a subcellular endosymbiotic relationship with chloroplasts of the marine heterokont alga Vaucheria litorea.

<i>Elysia crispata</i> Species of gastropod

Elysia crispata, common name the lettuce sea slug or lettuce slug, is a large and colorful species of sea slug, a marine gastropod mollusk.

A valve is each articulating part of the shell of a mollusc or another multi-shelled animal such as brachiopods and some crustaceans. Each part is known as a valve or in the case of chitons, a "plate". Members of two classes of molluscs, the Bivalvia (clams) and the Polyplacophora (chitons), have valves.

<i>Elysia pusilla</i> Species of gastropod

Elysia pusilla is a species of small sea slug, a marine gastropod mollusk in the family Plakobranchidae. It is a sacoglossan.

Mollusca Large phylum of invertebrate animals

Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks. Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species. The proportion of undescribed species is very high. Many taxa remain poorly studied.

<i>Lambis lambis</i> Species of gastropod

Lambis lambis, common name the spider conch, is a species of large sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs.

Juliidae Family of gastropods

Juliidae, common name the bivalved gastropods, is a family of minute sea snails, marine gastropod mollusks or micromollusks in the superfamily Oxynooidea, an opisthobranch group.

<i>Plakobranchus ocellatus</i> Species of gastropod

Plakobranchus ocellatus is a species of sea slug, a sacoglossan, a marine opisthobranch gastropod mollusk in the family Plakobranchidae. It is found in shallow water in the Indo-Pacific region.

Julia (gastropod) Genus of gastropods

Julia is a minute sea snails genus, marine gastropod mollusks or micromollusks in the superfamily Oxynooidea.

Julia burni is a species of a sea snail with shell of two separate hinged pieces or valves, a marine gastropod mollusk in the family Juliidae.

<i>Julia japonica</i> Species of gastropod

Julia japonica is a species of a sea snail with a shell comprising two separate hinged pieces or valves. It is a marine gastropod mollusk in the family Juliidae.

Julia mishimaensis is a species of a sea snail with a shell comprising two separate hinged pieces or valves. It is a marine gastropod mollusk in the family Juliidae.

<i>Lacuna vincta</i> Species of gastropod

Lacuna vincta, commonly known as the northern lacuna, the wide lacuna, the northern chink shell, or the banded chink shell, is a species of sea snail, a marine gastropod mollusk in the family Littorinidae, the winkles or periwinkles. It is found intertidally and in shallow waters in both the northern Atlantic Ocean and the northern Pacific Ocean. It is a herbivore, feeding on seaweed and diatoms with its toothed radula.

<i>Macrostrombus costatus</i>

Macrostrombus costatus, formerly known as Strombus costatus and Lobatus costatus, or commonly known as the milk conch, is a species of large sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs. They are an edible species and important food source for the inhabitants of where they are found. Conchs are most notable for their medium to large-sized ornamental shells. Milk conchs are dispersed among the tropical waters of the Atlantic Ocean, along the coasts and islands of North, Central, and South America.

Elysia serca, the seagrass elysia or Caribbean seagrass elysia, is a species of sea slug, a marine gastropod mollusc in the family Plakobranchidae. Although this sea slug resembles a nudibranch, it is not a nudibranch; it belongs to the clade, Sacoglossa, the "sap-sucking" sea slugs. It was first described by Marcus in 1955 from specimens found in Brazil.

<i>Costasiella ocellifera</i> Species of gastropod

Costasiella ocellifera is a small species of sea slug, a shell-less marine gastropod mollusk in the family Costasiellidae. Costasiella ocellifera, and other members of the Costasiellidae family are often mistakenly classified as nudibranchs because they superficially resemble other species of that group, but they are actually a part of the Sacoglossa superorder of sea slugs, also known as the “sap-sucking sea slugs,” "crawling leaves" or the "solar-powered sea slugs." C. ocellifera was discovered by Simroth in 1895, and was initially classified as Doto ocellifera. The Brazilian species, Costasiella liliana, is a synonym of C. ocellifera.Costasiella ocellifera shows long-term retention of functional kleptoplasty.

References

  1. Gould A. A. (1862). "Descriptions of new genera and species of shells". Proceedings of the Boston Society of Natural History8: 280-285.
  2. "WoRMS - World Register of Marine Species". www.marinespecies.org. Retrieved 2022-04-19.
  3. 1 2 3 4 5 6 Alison., Kay, Elizabeth (1962). Julia exquisita Gould, a bivalved gastropod. OCLC   16340548.
  4. 1 2 3 Händeler, Katharina. Evolution of Sacoglossa (Opisthobranchia) with emphasis on their food (Ulvophyceae) and the ability to incorporate kleptoplasts. OCLC   838369697.
  5. 1 2 3 Muro, Sandra. "Phylogeography and Cryptic Speciation in the Bivalved Sea Slug Genus Julia Gould, 1862".{{cite journal}}: Cite journal requires |journal= (help)
  6. Volland, Martin (2020). "Rheinische Friedrich-Wilhelms-Universität und Zoologisches Forschungsmuseum Alexander Koenig (Hrsg.): Objektwelten als Kosmos – Von Alexander von Humboldt zum Netzwerk Bonner Wissenschaftssammlungen. (Katalog zur Sonderausstellung im Zoologischen Forschungsmuseum Alexander Koenig, Bonn, 14.11.2019–22.03.2020.) Bonn: Rheinische Friedrich-Wilhelms-Universität; Zoologisches Forschungsmuseum Alexander Koenig, 2019. 348 pp. ISBN 978-3-9821310-0-9. Preis: € 25,00". Anthropos. 115 (2): 623–625. doi:10.5771/0257-9774-2020-2-623. ISSN   0257-9774.
  7. 1 2 3 4 Wong, Nur Leena W. S.; Sigwart, Julia D. (2019-05-23). "Natural history clues to the evolution of bivalved gastropods (Mollusca: Gastropoda: Sacoglossa: Juliidae)". Marine Biodiversity. 49 (4): 1997–2007. doi:10.1007/s12526-019-00960-0. ISSN   1867-1616. S2CID   162184423.
  8. LAETZ, ELISE; CHRISTA, GREGOR; HÄNDELER, KATHARINA; WÄGELE, HEIKE (2014-12-09). "The Cylindrobulla / Ascobulla complex—unraveling problems in identification and adding to Cylindrobulla diversity (Gastropoda, Heterobranchia, Sacoglossa) by describing a new species". Zootaxa. 3893 (3): 339–362. doi:10.11646/zootaxa.3893.3.2. ISSN   1175-5334. PMID   25544526.