Bullacta exarata
Encyclopedia
Bullacta exarata, common name
the Korean mud snail, is a species
of a sea snail
or bubble snail, a marine
gastropod mollusc in the family
Haminoeidae
, the bubble snails.
Bullacta exarata is a commercially important mollusc which is used as a food item in eastern China.
Bullacta is the type genus of the family Bullactidae Thiele, 1926, as shown in the taxonomy of the Gastropoda by Bouchet & Rocroi (2005)
.
Based on phylogenetic genetic analysis by Malaquias (2010), Bullacta exarata should be placed in the family Haminoeidae
.
and East China Sea
s from Hainan
to the Bohai Sea
in north-eastern China, the western coast and south coast of Korea and Japan.
An ecotype
of this snail introduced from further south has became invasive
in Laizhou Bay
, with population densities of over 160 snails per square meter.
is bullate, fairly thick, white, spirally striate, with a well developed periostracum
. There is no spire
and no umbilicus. The columella is smooth and simple. The aperture
extends for the whole length of the shell, and is narrower above than below. The apertural lip extends upwards beyond the apex
of the shell.
The height of the shell is 8 mm and the width of the shell is 6 mm.
The animal cannot withdraw itself into the shell, which contains the visceral hump only. The cephalic disc is large and slipper-shaped, feebly emarginate on the dorsal surface behind and with a narrow free margin.
The cephalic disc, which is rounded in front, occupies about half of the whole bulk in a contracted state. The edge of the mantle
is smooth, without processes of any kind. It, the edge of the mantle (which is slightly retroverted over that of the shell), the foot and the epipodia are (in alcohol) of a pale green colour. The greater part of the mantle, however, under the shell is colourless and transparent. The foot is short, truncate before and behind, and with the epipodia (in much contracted specimens) apparently not well developed. The eyes are minute and quite invisible on the surface. The eyespots are deeply sunk in the tissues. The gill, which is situated far back on the right side, is large and consists of a considerable number of fleshly lobes.
Digestive system
: The mouth is a minute tranverse slit in the front of the cephalic disc. The jawss are large, but imperfectly cornified. The jaws are angular and minutely, irregularly serrate. They are composed of numerous minute prismatic rods. On the margin many of these rods are transverse and project slightly, forming a minute serration. The radular sack is small. The radula
has the formula 12.1.1.1.12. The central tooth is a simple flat triangular plate. The single lateral tooth is well differentiated from the marginal teeth, from which it is separated by a considerable space, and points in the opposite direction. The marginal teeth are slender, elongate, curved rod-like bodies somewhat expanded at the base. They decrease in size gradually from the second or third marginal, which is slightly larger than the first, outwards.
There is a long, narrow, thin-walled oesophagus with a single coil; before entering the muscular gizzard it is considerably dilated. A
longitudinal strand of muscular tissue runs up its dorsal surface for a short distance from the gizzard. The gizzard is large and it contains three horn-shaped, transversely ridged chitinous plates arranged in a triangle. It is maintained in position by a stout transverse muscle on either side, the proximal end of the muscle being fixed to a constriction in the outer wall of the gizzard. The gizzard contains three large, stout chitinous bodies, which are smooth and heart-shaped at their base on its external surface. Internally they are convex, curved and tapering, with stout, somewhat serrate reversed V-shaped transverse ridges. The intestine after leaving the gizzard bears three small, almost spherical, diverticula, one behind the base of each of the chitinous plates. The wall of the intestine is thin and its structure simple; it has a single closely adpressed bend.
Reproductive system
: The male intromittent organ is provided with an elongate chitinous stylet. The penis is enclosed in an oval sack. When extracted therefrom it is an almost cylindrical organ with two coils, or constrictions, in its course, bluntly pointed at the apex and much contracted proximally. Its walls are highly muscular, but all the muscles are longitudinal and there is no circular muscular bulb. Its outstanding feature is the presence of a long, slender, sharply pointed, scimitar-shaped, black, horny stylet with a saddle-shaped base which is sometimes prolonged into a long, sharply pointed spur. In some individuals, however, the spur is completely absent.
The female genitalia include a well-developed uterus
but no spermatheca
. The hermaphrodite gland is small in immature specimen.
Nervous system
: The central nervous system
closely resembles that of Atys cylindrica.
Bullacta exarata is a hermaphroditic species.
Its life cycle has been extensively studied:
Bullacta exarata feeds on diatoms. It is an important consumer in the tidal flat ecosystem.
Bacteria
indentified in the digestive system
of Bullacta exarata include the genera Photobacterium
, Bacillus
, Pseudomonas
, Vibrio
, some genera from the family Enterobacteriaceae
and others.
According to the measurement of hygienic indicator bacteria Escherichia coli
in 2001, the meat of Bullacta exarata meets national standards (3 cells of Escherichia coli in one gram of fresh meat) in Shanghai
province and in most of Zhejiang
province.
Heavy metals in the tissues of Bullacta exarata from the Yangtze Estuary were measured by Lu et al. in 2001. In Shanghai, the coast is seriously polluted
and measured pollutants in the meat of Bullacta exarata were in 2003 as follows:
.
Mass mortalities of Bullacta exarata in Zhejiang in 1995 caused economic losses. The species is being cultivated in mariculture
, especially in Zhejiang
Province, where there was a cultivated area of 8,000 ha in 1999.
For example Bullacta exarata was the main farming species at the farming area of about 10 100 mu (6.73266 km2) in the Cixi City
, with an estimated annual output of 15 million RMB.
Bullacta exarata has high nutrition
value. There is high amount of omega-3 fatty acid
s in the canned meat of Bullacta exarata (there is 600 mg of eicosapentaenoic acid
in 100 g of meat).
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
the Korean mud snail, is a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of a sea snail
Sea snail
Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....
or bubble snail, a 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 mollusc in 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...
Haminoeidae
Haminoeidae
Haminoeidae, commonly known as the haminoeid bubble snail family, is a taxonomic family of sea snails, marine opisthobranch gastropod mollusks in the superfamily Haminoeoidea....
, the bubble snails.
Bullacta exarata is a commercially important mollusc which is used as a food item in eastern China.
Taxonomy
Bullacta exarata is the only species in the genus Bullacta. cf.Bullacta is the type genus of the family Bullactidae Thiele, 1926, as shown in the taxonomy of the Gastropoda by Bouchet & Rocroi (2005)
Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)
The taxonomy of the Gastropoda as it was revised by Philippe Bouchet and Jean-Pierre Rocroi is currently the most up-to-date overall system for classifying gastropod mollusks...
.
Based on phylogenetic genetic analysis by Malaquias (2010), Bullacta exarata should be placed in the family Haminoeidae
Haminoeidae
Haminoeidae, commonly known as the haminoeid bubble snail family, is a taxonomic family of sea snails, marine opisthobranch gastropod mollusks in the superfamily Haminoeoidea....
.
Distribution
Bullacta exarata is endemic to coastlines of the SouthSouth China Sea
The South China Sea is a marginal sea that is part of the Pacific Ocean, encompassing an area from the Singapore and Malacca Straits to the Strait of Taiwan of around...
and East China Sea
East China Sea
The East China Sea is a marginal sea east of China. It is a part of the Pacific Ocean and covers an area of 1,249,000 km² or 750,000 square miles.-Geography:...
s from Hainan
Hainan
Hainan is the smallest province of the People's Republic of China . Although the province comprises some two hundred islands scattered among three archipelagos off the southern coast, of its land mass is Hainan Island , from which the province takes its name...
to the Bohai Sea
Bohai Sea
Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of Northeastern and North China. It is approximately 78,000 km2 Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of...
in north-eastern China, the western coast and south coast of Korea and Japan.
An ecotype
Ecotype
In evolutionary ecology, an ecotype,Greek: οίκος = home and τύπος = type, coined by Göte Turesson in 1922 sometimes called ecospecies, describes a genetically distinct geographic variety, population or race within species , which is adapted to specific environmental conditions.Typically, ecotypes...
of this snail introduced from further south has became invasive
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
in Laizhou Bay
Laizhou Bay
Laizhou Bay is the southern arm of the Bohai Sea , which is a large relatively shallow extension of Korea Bay behind the Liaodong Peninsula to the north, and the Shandong Peninsula to the south...
, with population densities of over 160 snails per square meter.
Description
The shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
is bullate, fairly thick, white, spirally striate, with a well developed periostracum
Periostracum
The periostracum is a thin organic coating or "skin" which is the outermost layer of the shell of many shelled animals, including mollusks and brachiopods. Among mollusks it is primarily seen in snails and clams, i.e. in bivalves and gastropods, but it is also found in cephalopods such as the...
. There is no spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
and no umbilicus. The columella is smooth and simple. The aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
extends for the whole length of the shell, and is narrower above than below. The apertural lip extends upwards beyond the apex
Apex (mollusc)
Apex is an anatomical term for the tip of the mollusc shell of a gastropod, scaphopod, or cephalopod mollusc.-Gastropods:The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod...
of the shell.
The height of the shell is 8 mm and the width of the shell is 6 mm.
The animal cannot withdraw itself into the shell, which contains the visceral hump only. The cephalic disc is large and slipper-shaped, feebly emarginate on the dorsal surface behind and with a narrow free margin.
The cephalic disc, which is rounded in front, occupies about half of the whole bulk in a contracted state. The edge of the mantle
Mantle (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...
is smooth, without processes of any kind. It, the edge of the mantle (which is slightly retroverted over that of the shell), the foot and the epipodia are (in alcohol) of a pale green colour. The greater part of the mantle, however, under the shell is colourless and transparent. The foot is short, truncate before and behind, and with the epipodia (in much contracted specimens) apparently not well developed. The eyes are minute and quite invisible on the surface. The eyespots are deeply sunk in the tissues. The gill, which is situated far back on the right side, is large and consists of a considerable number of fleshly lobes.
Digestive system
Digestive system of gastropods
The digestive system of gastropods has evolved to suit almost every kind of diet and feeding behavior. Gastropods as the largest taxonomic class of the mollusca are very diverse indeed: the group includes carnivores, herbivores, scavengers, filter feeders, and even parasites.In particular, the...
: The mouth is a minute tranverse slit in the front of the cephalic disc. The jawss are large, but imperfectly cornified. The jaws are angular and minutely, irregularly serrate. They are composed of numerous minute prismatic rods. On the margin many of these rods are transverse and project slightly, forming a minute serration. The radular sack is small. The radula
Radula
The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately 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...
has the formula 12.1.1.1.12. The central tooth is a simple flat triangular plate. The single lateral tooth is well differentiated from the marginal teeth, from which it is separated by a considerable space, and points in the opposite direction. The marginal teeth are slender, elongate, curved rod-like bodies somewhat expanded at the base. They decrease in size gradually from the second or third marginal, which is slightly larger than the first, outwards.
There is a long, narrow, thin-walled oesophagus with a single coil; before entering the muscular gizzard it is considerably dilated. A
longitudinal strand of muscular tissue runs up its dorsal surface for a short distance from the gizzard. The gizzard is large and it contains three horn-shaped, transversely ridged chitinous plates arranged in a triangle. It is maintained in position by a stout transverse muscle on either side, the proximal end of the muscle being fixed to a constriction in the outer wall of the gizzard. The gizzard contains three large, stout chitinous bodies, which are smooth and heart-shaped at their base on its external surface. Internally they are convex, curved and tapering, with stout, somewhat serrate reversed V-shaped transverse ridges. The intestine after leaving the gizzard bears three small, almost spherical, diverticula, one behind the base of each of the chitinous plates. The wall of the intestine is thin and its structure simple; it has a single closely adpressed bend.
Reproductive system
Reproductive system of gastropods
The reproductive system of gastropods varies greatly from one group to another within this very large and diverse taxonomic class of animals...
: The male intromittent organ is provided with an elongate chitinous stylet. The penis is enclosed in an oval sack. When extracted therefrom it is an almost cylindrical organ with two coils, or constrictions, in its course, bluntly pointed at the apex and much contracted proximally. Its walls are highly muscular, but all the muscles are longitudinal and there is no circular muscular bulb. Its outstanding feature is the presence of a long, slender, sharply pointed, scimitar-shaped, black, horny stylet with a saddle-shaped base which is sometimes prolonged into a long, sharply pointed spur. In some individuals, however, the spur is completely absent.
The female genitalia include a well-developed uterus
Uterus
The uterus or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species...
but no spermatheca
Spermatheca
The spermatheca , also called receptaculum seminis , is an organ of the female reproductive tract in insects, some molluscs, oligochaeta worms and certain other invertebrates and vertebrates...
. The hermaphrodite gland is small in immature specimen.
Nervous system
Nervous system of gastropods
The nervous system of gastropods consists of a series of paired ganglia connected by major nerve cords, and a number of smaller branching peripheral nerves.The brain of a gastropod consists of three pairs of ganglia, all located close to the oesophagus...
: The central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
closely resembles that of Atys cylindrica.
Ecology
The habitat for this species includes intertidal flats, including the supratidal zone and subtidal zone.Bullacta exarata is a hermaphroditic species.
Its life cycle has been extensively studied:
- Vitellogenesis (Ying & Yang, 2001)
- Oogenesis (Ying, 2002)
- Spermatogenesis (Ying et al., 2002)
- Reproductive system (Ying et al., 2002)
- Spermatozoa (Ying et al., 2004)
Bullacta exarata feeds on diatoms. It is an important consumer in the tidal flat ecosystem.
Bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
indentified in the digestive system
Digestive system of gastropods
The digestive system of gastropods has evolved to suit almost every kind of diet and feeding behavior. Gastropods as the largest taxonomic class of the mollusca are very diverse indeed: the group includes carnivores, herbivores, scavengers, filter feeders, and even parasites.In particular, the...
of Bullacta exarata include the genera Photobacterium
Photobacterium
Photobacterium is a genus of gram-negative bacteria in the family Vibrionaceae. Members of the genus are bioluminescent, that is they have the ability to emit light....
, Bacillus
Bacillus
Bacillus is a genus of Gram-positive, rod-shaped bacteria and a member of the division Firmicutes. Bacillus species can be obligate aerobes or facultative anaerobes, and test positive for the enzyme catalase. Ubiquitous in nature, Bacillus includes both free-living and pathogenic species...
, Pseudomonas
Pseudomonas
Pseudomonas is a genus of gammaproteobacteria, belonging to the family Pseudomonadaceae containing 191 validly described species.Recently, 16S rRNA sequence analysis has redefined the taxonomy of many bacterial species. As a result, the genus Pseudomonas includes strains formerly classified in the...
, Vibrio
Vibrio
Vibrio is a genus of Gram-negative bacteria possessing a curved rod shape, several species of which can cause foodborne infection, usually associated with eating undercooked seafood. Typically found in saltwater, Vibrio are facultative anaerobes that test positive for oxidase and do not form...
, some genera from the family Enterobacteriaceae
Enterobacteriaceae
The Enterobacteriaceae is a large family of bacteria that includes many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella and Shigella. This family is the only representative in the order Enterobacteriales of the class Gammaproteobacteria in the...
and others.
According to the measurement of hygienic indicator bacteria Escherichia coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
in 2001, the meat of Bullacta exarata meets national standards (3 cells of Escherichia coli in one gram of fresh meat) in Shanghai
Shanghai
Shanghai is the largest city by population in China and the largest city proper in the world. It is one of the four province-level municipalities in the People's Republic of China, with a total population of over 23 million as of 2010...
province and in most of Zhejiang
Zhejiang
Zhejiang is an eastern coastal province of the People's Republic of China. The word Zhejiang was the old name of the Qiantang River, which passes through Hangzhou, the provincial capital...
province.
Heavy metals in the tissues of Bullacta exarata from the Yangtze Estuary were measured by Lu et al. in 2001. In Shanghai, the coast is seriously polluted
Pollution in China
Pollution is causing serious problems in China.-Electronic waste:Electronic waste is being deported to China and is causing war, water and land based pollution...
and measured pollutants in the meat of Bullacta exarata were in 2003 as follows:
- 20.70 mg of petroleumPetroleumPetroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
hydrocarbons in one kg of wet weight (exceeds grade I of biological standard) - 13.10 mg of zincZincZinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
in one kg of wet weight - 33.60 mg of copperCopperCopper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
in one kg of wet weight (exceeds grade II of biological standard)
Human use
Bullacta exarata is a commercially important mollusc in eastern China. Common names in Mandarin Chinese include Tutie and Niluo . It is exported as a food source to Hong Kong, Macau, Taiwan and to Southeast AsiaSoutheast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
.
Mass mortalities of Bullacta exarata in Zhejiang in 1995 caused economic losses. The species is being cultivated in mariculture
Mariculture
Mariculture is a specialized branch of aquaculture involving the cultivation of marine organisms for food and other products in the open ocean, an enclosed section of the ocean, or in tanks, ponds or raceways which are filled with seawater. An example of the latter is the farming of marine fish,...
, especially in Zhejiang
Zhejiang
Zhejiang is an eastern coastal province of the People's Republic of China. The word Zhejiang was the old name of the Qiantang River, which passes through Hangzhou, the provincial capital...
Province, where there was a cultivated area of 8,000 ha in 1999.
For example Bullacta exarata was the main farming species at the farming area of about 10 100 mu (6.73266 km2) in the Cixi City
Cixi City
Cixi is a city within the sub-provincial city of Ningbo located in China's Zhejiang province.- History :The city was captured by British forces in the Battle of Tsekee on 15 March 1842 during the First Opium War...
, with an estimated annual output of 15 million RMB.
Bullacta exarata has high nutrition
Nutrition
Nutrition is the provision, to cells and organisms, of the materials necessary to support life. Many common health problems can be prevented or alleviated with a healthy diet....
value. There is high amount of omega-3 fatty acid
Omega-3 fatty acid
N−3 fatty acids are essential unsaturated fatty acids with a double bond starting after the third carbon atom from the end of the carbon chain....
s in the canned meat of Bullacta exarata (there is 600 mg of eicosapentaenoic acid
Eicosapentaenoic acid
Eicosapentaenoic acid is an omega-3 fatty acid. In physiological literature, it is given the name 20:5. It also has the trivial name timnodonic acid...
in 100 g of meat).
Further reading
- Ge B.-M., Bao Y.-X., Cheng H.-Y. & Zheng X. (2006). "Population Distribution of Bullacta exarata in Cixi Shore, Southern Hangzhou Bay in Summer". Fisheries Science. doi:cnki:ISSN:1003-1111.0.2006-11-001. abstract.
- Gu X., You Z., Wang Y., Ding W. & Xu H. (1997). "Preliminary study on growth of mud snail Bullacata exarata". Journal of Zhejiang College of Fisheries 16(1): 6-11. Li S.-g. (2005). "The Biology of Bullacta exarata (泥螺的生物学)". Reservoir Fisheries 4: 42-54. Liu H. (2003). "Technology for aquiculture of Bullacta exarata in benefit ponds in salt fields (盐场效益池泥螺养殖技术初探)". Jiangsu Province Salt Science & Technology 3: 15-16. Wang Y., You Z., Zuo H. & Wang G. (2003). "Study on Ecological Habit of Mud Slug, Bullacta exarata (养殖泥螺生态习性研究)". Journal Of Ningbo University (Natural Science & Engineering Edition) 3: 240-244. Wang Y.-n. & Yu H. (2006). "Techniques for Culture of Bullacta exarata in Retaining Water Intertidal Zone (泥螺的滩涂蓄水养殖技术)". Fisheries Science & Technology Information 5: 238-240. Xu P. (2003). "A Study on Breeding and Enhancement Technique of Bullacta exarata (Philipi) (泥螺Bullacta exarata(Philippi)育苗及增养殖技术探讨)". Modern Fisheries Information 4: 24-26.
- Ye S.-F. & Lu J.-J. (2001). "Characteristics and ecological significance of the developing population of Bullacata exarata (Philippi, 1848) (Mollusca: Gastropoda, Atyidae) in the Yangtze estuary, China". Resources and Environment in the Yangtze Basin 10(3): 216-222. doi:cnki:ISSN:1004-8227.0.2001-03-004. abstract. You Z., Wang Y. & Ding W. (1994). "Effects of environmental factors on Bullacta exarata (Gastropoda, Scaphandridae) at different developmental stages". Journal of Zhejiang College of Fisheries 13(2): 79-85. Zhang Z. (2001). "Technology Exploration of Pickled Bullacta exarata (腌制泥螺的工艺探讨)". Journal Of Shaoxing College Of Arts Ang Sciences（Natural Science) 7: 71-73.
- Zhu S.-Y., Wu Y.P., Sheng H. D. et al. (2008). "Artificial hybridization and juvenile nursery of Bullacta exarata". J. Zhejiang. Ocean. Univ. 1: 32-36. Natural Science. Zuo H., Wang Y., Xu J. & Wang G. (2005). "Key Technique on Bullacta exarata Culture (泥螺生态系管养的技术要点)". Fisheries Science 1: 29-30. 泥螺. (overview of Bullacta exarata).