Dwarf Pufferfish
   HOME

TheInfoList



OR:

The dwarf pufferfish (''Carinotetraodon travancoricus''), also known as the Malabar pufferfish, pygmy pufferfish, or pea pufferfish, is a small
freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...
pufferfish Tetraodontidae is a family of marine and freshwater fish in the order Tetraodontiformes. The family includes many familiar species variously called pufferfish, puffers, balloonfish, blowfish, blowers, blowies, bubblefish, globefish, swellfis ...
endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to
Kerala Kerala ( , ) is a States and union territories of India, state on the Malabar Coast of India. It was formed on 1 November 1956, following the passage of the States Reorganisation Act, by combining Malayalam-speaking regions of the erstwhile ...
and southern
Karnataka Karnataka ( ) is a States and union territories of India, state in the southwestern region of India. It was Unification of Karnataka, formed as Mysore State on 1 November 1956, with the passage of the States Reorganisation Act, 1956, States Re ...
in Southwest India. They are popular in aquaria for their bright colours and small size. At a maximum
total length Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured f ...
of 3.5 cm, dwarf pufferfish are one of the smallest pufferfish in the world. They closely resemble the related ''
Carinotetraodon imitator ''Carinotetraodon imitator'', commonly known as the dwarf Malabar pufferfish, is a freshwater pufferfish found in the Western Ghats of India, with little information available on its complete distribution. It is one of the smallest pufferfish ...
'', and the two can be difficult to distinguish. ''C. imitator'' was not recognised as a different species until 1999. Dwarf pufferfish dwell at the bottom of heavily
vegetated Vegetation is an assemblage of plants and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristi ...
waterways,
predating Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill ...
small animals. Unlike other species of pufferfish, they are found in large groups in the wild. They breed throughout most of the year, with spawning pairs producing 1–5 eggs in 1–4 day intervals.
Habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
and
overharvesting Overexploitation, also called overharvesting or ecological overshoot, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to ...
for the
aquarium trade Fishkeeping is a popular hobby, practiced by aquarists, concerned with keeping fish in a home aquarium or garden pond. It is a practice that encompasses the art of maintaining one's own aquatic ecosystem, featuring a lot of variety with various ...
threaten wild populations of dwarf pufferfish.


Taxonomy

The dwarf pufferfish was first described as ''Tetraodon (Monotretus) travancoricus'' in 1941 by S.L. Hora and K.K. Nair, with the type locality given as "
Pamba River The Pamba River (also called Pampa River) is the longest river in the Indian state of Kerala after Periyar (river), Periyar and Bharathappuzha, and the longest river in the erstwhile former princely state of Travancore. The Sabarimala Temple, d ...
, Central
Travancore The kingdom of Travancore (), also known as the kingdom of Thiruvithamkoor () or later as Travancore State, was a kingdom that lasted from until 1949. It was ruled by the Travancore Royal Family from Padmanabhapuram, and later Thiruvanan ...
". The use of parentheses indicates ''Monotretus'' is the
subgenus In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...
of ''Tetraodon''. ''Carinotetraodon'' was considered a
synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...
of ''Tetraodon'' until 1978, when J.C. Tyler treated it as a valid
genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
in a paper about ''
Carinotetraodon lorteti Somphong's puffer, redeye puffer or crested puffer (''Carinotetraodon lorteti'') is a small freshwater blowfish found in mainlands Southeast Asia such as Thailand, Cambodia, Vietnam. This fish has been collected in the past for the aquarium trade. ...
'', which was an opinion followed by M. Kottelat ''et al.'' in 1993 and K.K.P. Lim and M. Kottelat in 1995. The first use of ''"Carinotetraodon travancoricus"'' was in 1999 by R. Britz and M. Kottelat when first describing ''
Carinotetraodon imitator ''Carinotetraodon imitator'', commonly known as the dwarf Malabar pufferfish, is a freshwater pufferfish found in the Western Ghats of India, with little information available on its complete distribution. It is one of the smallest pufferfish ...
'', a superficially similar and closely related species previously mistaken for dwarf pufferfish. "''Carinotetraodon''" is derived from the
Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
word "''carina''" (keel-shaped, shell) and
Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...
words "''tetra''" (four) and "''odous''" (teeth). The justification for moving to ''Carinotetraodon'' was based largely on
osteological Osteology () is the scientific study of bones, practiced by osteologists . A subdiscipline of anatomy, anthropology, archaeology and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morp ...
evidence and not on the presence of skin
keel The keel is the bottom-most longitudinal structural element of a watercraft, important for stability. On some sailboats, it may have a fluid dynamics, hydrodynamic and counterbalancing purpose as well. The keel laying, laying of the keel is often ...
s, which other members of the genus have, but which had not been confirmed in dwarf pufferfish until one year later in aquarium literature. Specifically, dwarf pufferfish possess
vertebral Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spina ...
modifications and a reduced number of total vertebrae similar to other members of ''Carinotetraodon'', in addition to a small size and the presence of
sexual dimorphism Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...
, also found amongst other members of this genus. The following
cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...
is based on molecular evidence and demonstrates the
polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...
nature of the genus ''Carinotetraodon''. A polyphyletic genus is one in which members share common characteristics, but do not necessarily share an immediate common ancestor, and their placement is based on these shared traits rather than confirmed, empirical evidence. "''Carinotetraodon''" is represented in quotation marks to signify its polyphyletic status. Freshwater species are denoted with "FW". The cladogram is incomplete due to the absence of species like ''C. imitator'', which have not undergone mitogenome analyses.


Description

The maximum documented size is total length (TL), with individuals typically reaching less than TL, making dwarf pufferfish one of the smallest pufferfish in the world. Both sexes are primarily greenish-yellow, with dark green to brown-black
iridescent Iridescence (also known as goniochromism) is the phenomenon of certain surfaces that appear gradually to change colour as the angle of view or the angle of illumination changes. Iridescence is caused by wave interference of light in microstruc ...
patches on the flanks and
dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...
surface. Patterns and colouration vary considerably between individuals. Their
pectoral fins Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only b ...
are short, fan-shaped, and described as "slightly
emarginate The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade is divided into two or more leaflets) ...
", that is to say, slightly indented at the tip. The
dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...
and
anal fins Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only by ...
are situated opposite each other toward the posterior of the fish, both short and round, while the
caudal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...
is larger than the other fins and truncate, in that it terminates in a more-or-less vertical edge. Their bodies are round and oblong. As with other members of the genus, sexual dimorphism is apparent in mature fish, with males being more brightly coloured than females and having a yellow
ventral Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...
surface. Males can also have a dark stripe down the centre of their pale belly and iridescent, blue "eye wrinkle" patterns that females do not have. Females are more rounded, tend to be larger than males, and may have more small spots between their larger dark markings. Their abdomens are white, and they may have a yellow patch on their throat.


Natural defenses

All pufferfish can inflate, or "puff up", their bodies by quickly ingesting large amounts of water (or air when necessary) into their highly elastic stomachs. Inflating tires pufferfish and can put them at greater risk of predation. Like many other pufferfish, in the absence of
scales Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number ...
, dwarf pufferfish have skin spines on most of their body. These spines become erect when the fish is inflated. Dwarf pufferfish, like many other
Tetraodontiformes Tetraodontiformes (), also known as the Plectognathi, is an order of ray-finned fishes which includes the pufferfishes and related taxa. This order has been classified as a suborder of the order Perciformes, although recent studies have found ...
, produce
tetrodotoxin Tetrodotoxin (TTX) is a potent neurotoxin. Its name derives from Tetraodontiformes, an Order (biology), order that includes Tetraodontidae, pufferfish, porcupinefish, ocean sunfish, and triggerfish; several of these species carry the toxin. Alt ...
, a highly lethal
neurotoxin Neurotoxins are toxins that are destructive to nervous tissue, nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insult (medical), insultsSpencer 2000 that can adversely affect function ...
for which there is no antidote. The neurotoxin accumulates in the glands of the
epidermis The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and Subcutaneous tissue, hypodermis. The epidermal layer provides a barrier to infection from environmental pathogens and regulates the ...
(surface layer of skin),
ovaries The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are endocr ...
, and
liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...
s of pufferfish. These traits are
anti-predator adaptation Anti-predator adaptations are mechanisms developed through evolution that assist Predation, prey organisms in their constant struggle against predators. Throughout the animal kingdom, adaptations have evolved for every stage of this struggle, na ...
s. The pufferfish's ability to inflate makes it difficult to swallow or bite, and the tetrodotoxin makes it unpalatable or even deadly for other fish. Biologists believe these adaptations
evolved Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...
because of the slow swimming speeds of pufferfish.


Resemblance to ''Carinotetraodon imitator''

''
Carinotetraodon imitator ''Carinotetraodon imitator'', commonly known as the dwarf Malabar pufferfish, is a freshwater pufferfish found in the Western Ghats of India, with little information available on its complete distribution. It is one of the smallest pufferfish ...
'' is a species of related pufferfish closely resembling dwarf pufferfish. They are of similar size, shape, patterns, and colouration. Both species are found within the same region and may be
sympatric In biology, two closely related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter each other. An initially interbreeding population that splits into two or more distinct spe ...
, possibly inhabiting the same waters. Until 1999, ''C. imitator'' was mistaken as the same species, and the two could be found together in aquaria and were widely available in the international aquarium trade, both sold as dwarf pufferfish. Dwarf pufferfish can be distinguished from their congener (a member of the same genus), as ''C. imitator'' have smaller, faint blotches compared to dwarf pufferfish, as well as greatly reduced body spination. Male dwarf pufferfish have a darker yellow colouration and an iridescent "eye wrinkle" not found in males of ''C. imitator''.


Distribution and habitat

Although closely related to marine pufferfish, they are not found in salt water, and reports to the contrary are based on misidentification. Dwarf pufferfish are one of only 27 known species of Tetraodontidae adapted to freshwater. They are a
potamodromous Fish migration is animal migration, mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few ...
species, meaning they migrate within freshwater river systems, and are endemic to rivers, lakes, and
estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...
in Kerala and southern Karnataka in the Western Ghats of
Peninsular India South India, also known as Southern India or Peninsular India, is the southern part of the Deccan Peninsula in India encompassing the states of Andhra Pradesh, Karnataka, Kerala, Tamil Nadu and Telangana as well as the Union territories of In ...
. They can be found in waters with a pH of 7.5–8.3 and temperatures of . Inhabiting heavily
vegetated Vegetation is an assemblage of plants and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristi ...
waters with beds of gravel and rock or
clay loam Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–si ...
with silt and sand, the species is reported from 13 rivers in Kerala, lakes such as
Vembanad Vembanad () is the longest lake in India, and the largest in the state of Kerala. The lake has an area of 2,033 square kilometers and a maximum length of 96.5 km. Spanning three districts in the state of Kerala, it is known as Vembanad L ...
, the
Nilambur Nilambur () is a major town, a municipality and a Taluk in the Malappuram district of the Indian state of Kerala. It is located close to the Nilgiri Mountains, Nilgiris range of the Western Ghats on the banks of the Chaliyar River. This place is ...
harbours, and Kallar Stream, part of the
Neyyar Wildlife Sanctuary The Neyyar Wildlife Sanctuary in the southern state of Kerala in India is spread over the southeast corner of the Western Ghats, and covers a total area of . It is located between 77° 8’ to 77° 17’ east longitude and 8° 29’ to 8° 37 ...
. They have been reported as rare in
Bharathapuzha The Bharathappuzha ("River of Bhārata"), also known as the Nila River, is a river in the Indian states of Tamil Nadu and Kerala. With a length of 209 km, it is the second longest river that flows through Kerala after the Periyar. It fl ...
and the
Nilgiri Biosphere Reserve The Nilgiri Biosphere Reserve is a biosphere reserve in the Nilgiri Mountains of the Western Ghats in South India. It is the largest protected forest area in India, spreading across Tamil Nadu, Karnataka and Kerala. It includes the protected ...
. The species was also found in inundated brickyards in
Puthukkad Puthukkad is a town on the banks of Kurumali River, also known as Mupliyam River, in Kerala. The town is to the south of Thrissur, to the north of Chalakudy, and west of Cheruval. The National highway NH 544 passes through this town. Tran ...
, as well as ditches, ponds,
irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...
channels Channel, channels, channeling, etc., may refer to: Geography * Channel (geography), a landform consisting of the outline (banks) of the path of a narrow body of water. Australia * Channel Country, region of outback Australia in Queensland and pa ...
, and artificial tanks or abandoned water bodies in paddy fields. Their presence in small, isolated water bodies is likely due to unintentional dispersal by
waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which i ...
.


Conservation status

Several researchers have considered the species
endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...
, though with no rationale provided. The dwarf pufferfish is officially classified as vulnerable on the
IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...
due to declining populations because of
damming A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aqua ...
, indiscriminate
deforestation Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...
for agriculture, pollution from
wastewater Wastewater (or waste water) is water generated after the use of freshwater, raw water, drinking water or saline water in a variety of deliberate applications or processes. Another definition of wastewater is "Used water from any combination of do ...
, and, primarily,
overfishing Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing Fish stocks, fish stock), resu ...
for the aquarium trade. In 2010, some researchers estimated that the population would decline by 30–40% from 2005 to 2015, while others estimated it had already declined by the same amount between 2005 and 2010.


Diet and behaviour

Dwarf pufferfish are euryphagous
carnivores A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose nutrition and energy requirements are met by consumption of animal tissues (mainly mu ...
in that they consume a wide variety of animals. Dwarf pufferfish favour insect
larvae A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect developmental biology, development such as insects, some arachnids, amphibians, or cnidarians typical ...
but will rely on
crustaceans Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of Arthropod, arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquat ...
and
annelids The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to vario ...
as alternate feed when the availability of preferable prey decreases. Their diet in the wild mainly consists of small animals such as water fleas,
rotifer The rotifers (, from Latin 'wheel' and 'bearing'), sometimes called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic Coelom#Pseudocoelomates, pseudocoelomate animals. They were first describ ...
s,
copepod Copepods (; meaning 'oar-feet') are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (living in the water column), some are benthos, benthic (living on the sedimen ...
s, and
seed shrimp Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 33,000 species (only 13,000 of which are extant) have been identified,Brandão, S.N.; Antonietto, L.S; Nery, D.G.; Santos, S.G.; Karano ...
, and aquatic larvae such as those of
Odonata Odonata is an order of predatory flying insects that includes the dragonflies and damselflies (as well as the '' Epiophlebia'' damsel-dragonflies). The two major groups are distinguished with dragonflies (Anisoptera) usually being bulkier with ...
,
Hemiptera Hemiptera (; ) is an order of insects, commonly called true bugs, comprising more than 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from ...
,
mayflies Mayflies (also known as shadflies or fishflies in Canada and the upper Midwestern United States, as Canadian soldiers in the American Great Lakes region, and as up-winged flies in the United Kingdom) are aquatic insects belonging to the order ...
, and
flies Flies are insects of the Order (biology), order Diptera, the name being derived from the Ancient Greek, Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwin ...
, with some amounts of plant matter, largely
diatoms A diatom (Neo-Latin ''diatoma'') is any member of a large group comprising several Genus, genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of Earth's B ...
and
green algae The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ...
. Sand and detritus, presumably ingested by mistake when feeding on small, bottom-dwelling animals, have also been found in their gut. In captivity, dwarf pufferfish benefit from a varied diet and will eat small
freshwater snails Freshwater snails are gastropod mollusks that live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs t ...
,
shrimps A shrimp (: shrimp ( US) or shrimps ( UK)) is a crustacean with an elongated body and a primarily swimming mode of locomotion – typically Decapods belonging to the Caridea or Dendrobranchiata, although some crustaceans outside of this orde ...
, as well as foods like frozen
mussel Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other ...
meat or other frozen
shellfish Shellfish, in colloquial and fisheries usage, are exoskeleton-bearing Aquatic animal, aquatic invertebrates used as Human food, food, including various species of Mollusca, molluscs, crustaceans, and echinoderms. Although most kinds of shellfish ...
. They will also readily eat live foods such as red and white
mosquito Mosquitoes, the Culicidae, are a Family (biology), family of small Diptera, flies consisting of 3,600 species. The word ''mosquito'' (formed by ''Musca (fly), mosca'' and diminutive ''-ito'') is Spanish and Portuguese for ''little fly''. Mos ...
larvae and other small animals they would predate in the wild. Dwarf pufferfish are commonly associated with plants in the genus
Cabomba ''Cabomba'' is a genus of perennial, rhizomatous, aquatic herbs in the family Cabombaceae native to tropical and subtropical America. It has divided submerged leaves in the shape of a fan (hence the vernacular name fanwort) and is much favoure ...
, and the presence of these plants has been shown to reduce mortality among captive specimens. Dwarf pufferfish are a slow-swimming,
demersal The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer o ...
(bottom-dwelling) species. Unlike many pufferfish species, which are primarily solitary and potentially aggressive or territorial between
conspecifics Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organism ...
(members of the same species), dwarf pufferfish are found in large
shoals In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material, and rises from the bed of a body of water close to the surface or ...
, occasionally consisting of hundreds of individuals. They are found mainly during the summer months of January to May and rarely during the rainy season. Shoaling fish experience stress or weight loss when kept in solitude or in groups too small.


Reproduction

In the wild, males with ripe
gonads A gonad, sex gland, or reproductive gland is a mixed gland and sex organ that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, ...
have been found during all months of the year but December and January, with the peak spawning period extending from May to August, concurring with the
South-West monsoon A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with annual latitudinal oscill ...
period. Within the Pamba River, the minimum size at which half the population becomes sexually mature is approximately . Environmental and dietary conditions may influence the maturation rate of individuals. The mid-dorsal and mid-ventral skin ridges of males become brown in colour during the spawning season. The belly of the female will swell, and the courting male will frequently chase the female and nibble at its belly. The female will then search for a suitable location to spawn while the male chases away other males. In the aquarium, dwarf pufferfish are often plant-spawners, laying eggs in plants, including
java moss Java moss is a common name for multiple plants and may refer to: *'' Taxiphyllum barbieri'' *'' Vesicularia dubyana'' Hypnaceae {{Short pages monitor