Paedocypris
Encyclopedia
Paedocypris is a genus
of cyprinid
fish found in Southeast Asia
where it occurs in Malaysia and Indonesia
. Three species are known.
Paedocypris progenetica has been claimed to be the smallest known species of fish
and vertebrate
in the world. The smallest mature female measured 7.9 mm and the largest known individual 10.3 mm.
from Switzerland and Tan Heok Hui from the Raffles Museum of Biodiversity Research and the National University of Singapore
in 1996. Their osteology was studied by Ralf Britz at London's Natural History Museum
. In 1994, the same ichthyologists had already discovered in Sarawak (Malaysian part of Borneo) another miniature species of the same genus Paedocypris. Like P. progenetica, P. micromegethes was found in the slow-flowing blackwater streams and peat swamps.
The genus, Paedocyrpis, and two species, Paedocypris progenetica and Paedocypris micromegethes, were first described in 2006. Paideios is Greek
for children and Cypris is Greek for Venus
and is a common suffix for cyprinid
genera; the gender
is feminine. Progenetica (from the word progenetic) is used as an adjective
. Micromegethes is Greek for small in size, and is used as a noun in apposition
.
Paedocypris is considered a danionin genus by Tyson Roberts. It was found that Sundadanio
and Paedocypris share a sister group
relationship, supporting its close relationship to danionin genera; however, this study included danionins among the subfamily Rasborinae.
fin
s, with the first ray terminating with a hook-like projection of keratinized skin, supported by hypertrophied pelvic musculature. Males also have a pad of keratinized skin in front of the pelvic fins. It is hypothesized that these modified fins are used to grasp the female during mating, or to keep position over a spawning surface.
and vertebrate
in the world. The smallest mature female is only 7.9 millimetres (.31 in) standard length
, smaller than the female of any other vertebrate species. The largest known individual is 10.3 mm (.41 in).
Male individuals of the species anglerfish
Photocorynus spiniceps
have been documented to be 6.2-7.3 mm at maturity, and thus claimed to be a smaller species. However, these survive only by sexual parasitism
, and the female individuals reach the significantly larger size of 50.5 mm.
n island of Sumatra
.
Paedocypris micromegethes lives in the peat swamps of Sarawak
(Borneo
). Their small size helps them to survive through extreme droughts, as they can live in small remaining puddles of acid water (pH as low as 2.9, at least 100 times more acidic than rainwater). Their habitat is threatened by forest fires, logging and plantations.
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 cyprinid
Cyprinid
The family Cyprinidae, from the Ancient Greek kyprînos , consists of the carps, the true minnows, and their relatives . Commonly called the carp family or the minnow family, its members are also known as cyprinids...
fish found in Southeast Asia
Southeast 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...
where it occurs in Malaysia and Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
. Three species are known.
Paedocypris progenetica has been claimed to be the smallest known species of fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
and vertebrate
Vertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...
in the world. The smallest mature female measured 7.9 mm and the largest known individual 10.3 mm.
Species
- Paedocypris carbunculus Britz & KottelatMaurice KottelatDr. Maurice Kottelat is a Swiss ichthyologist.In 1976 he entered the University of Neuchâtel where he obtained his diploma in 1987. In 1980 he went to Thailand where he began his field research on Southeast Asiatic and Indonesian fresh water fish species...
, 2008 - Paedocypris micromegethesPaedocypris micromegethesPaedocypris micromegethes is a species of cyprinid fish endemic to Malaysia where it is found in peat swamps. It is one of the smallest vertebrates in the world with females reaching a maximum size of 11.6 mm....
KottelatMaurice KottelatDr. Maurice Kottelat is a Swiss ichthyologist.In 1976 he entered the University of Neuchâtel where he obtained his diploma in 1987. In 1980 he went to Thailand where he began his field research on Southeast Asiatic and Indonesian fresh water fish species...
, Britz, H. H. Tan & Witte, 2006 - Paedocypris progeneticaPaedocypris progeneticaPaedocypris progenetica is a species of cyprinid fish endemic to Indonesia where it is found in peat swamps and blackwater streams. It is one of the smallest vertebrates in the world with females reaching a maximum size of 10.3 mm, males 9.8 mm and the smallest mature specimen, a female, measured...
KottelatMaurice KottelatDr. Maurice Kottelat is a Swiss ichthyologist.In 1976 he entered the University of Neuchâtel where he obtained his diploma in 1987. In 1980 he went to Thailand where he began his field research on Southeast Asiatic and Indonesian fresh water fish species...
, Britz, H. H. Tan & Witte, 2006
Taxonomy
Two species were discovered and identified by ichthyologists Maurice KottelatMaurice Kottelat
Dr. Maurice Kottelat is a Swiss ichthyologist.In 1976 he entered the University of Neuchâtel where he obtained his diploma in 1987. In 1980 he went to Thailand where he began his field research on Southeast Asiatic and Indonesian fresh water fish species...
from Switzerland and Tan Heok Hui from the Raffles Museum of Biodiversity Research and the National University of Singapore
National University of Singapore
The National University of Singapore is Singapore's oldest university. It is the largest university in the country in terms of student enrollment and curriculum offered....
in 1996. Their osteology was studied by Ralf Britz at London's Natural History Museum
Natural History Museum
The Natural History Museum is one of three large museums on Exhibition Road, South Kensington, London, England . Its main frontage is on Cromwell Road...
. In 1994, the same ichthyologists had already discovered in Sarawak (Malaysian part of Borneo) another miniature species of the same genus Paedocypris. Like P. progenetica, P. micromegethes was found in the slow-flowing blackwater streams and peat swamps.
The genus, Paedocyrpis, and two species, Paedocypris progenetica and Paedocypris micromegethes, were first described in 2006. Paideios is Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
for children and Cypris is Greek for Venus
Venus (mythology)
Venus is a Roman goddess principally associated with love, beauty, sex,sexual seduction and fertility, who played a key role in many Roman religious festivals and myths...
and is a common suffix for cyprinid
Cyprinid
The family Cyprinidae, from the Ancient Greek kyprînos , consists of the carps, the true minnows, and their relatives . Commonly called the carp family or the minnow family, its members are also known as cyprinids...
genera; the gender
Grammatical gender
Grammatical gender is defined linguistically as a system of classes of nouns which trigger specific types of inflections in associated words, such as adjectives, verbs and others. For a system of noun classes to be a gender system, every noun must belong to one of the classes and there should be...
is feminine. Progenetica (from the word progenetic) is used as an adjective
Adjective
In grammar, an adjective is a 'describing' word; the main syntactic role of which is to qualify a noun or noun phrase, giving more information about the object signified....
. Micromegethes is Greek for small in size, and is used as a noun in apposition
Apposition
Apposition is a grammatical construction in which two elements, normally noun phrases, are placed side by side, with one element serving to define or modify the other. When this device is used, the two elements are said to be in apposition...
.
Paedocypris is considered a danionin genus by Tyson Roberts. It was found that Sundadanio
Sundadanio
Sundadanio is a genus of cyprinid fishes from the Malay Archipelago. There are currently eight described species in this genus.-Species:* Sundadanio atomus Conway, Kottelat & H. H. Tan, 2011* Sundadanio axelrodi...
and Paedocypris share a sister group
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...
relationship, supporting its close relationship to danionin genera; however, this study included danionins among the subfamily Rasborinae.
Appearance
Their miniature transparent body lacks typical features characteristic of adult fish, for instance a bony skull structure around its brain, and it retains the post-anal larval-fin-fold along the ventral edge of the caudal peduncle, characteristic of fish larvae. They have a unique sexual dimorphism: The males have highly modified pelvicPelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
fin
Fin
A fin is a surface used for stability and/or to produce lift and thrust or to steer while traveling in water, air, or other fluid media, . The first use of the word was for the limbs of fish, but has been extended to include other animal limbs and man-made devices...
s, with the first ray terminating with a hook-like projection of keratinized skin, supported by hypertrophied pelvic musculature. Males also have a pad of keratinized skin in front of the pelvic fins. It is hypothesized that these modified fins are used to grasp the female during mating, or to keep position over a spawning surface.
Smallest vertebrate
Paedocypris progenetica has been claimed to be the smallest known species of fishFish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
and vertebrate
Vertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...
in the world. The smallest mature female is only 7.9 millimetres (.31 in) standard length
Fish measurement
Fish measurement refers to the measuring of the length of individual fish and of various parts of their anatomy. These data are used in many areas of ichthyology, including taxonomy and fisheries biology.-Overall length:...
, smaller than the female of any other vertebrate species. The largest known individual is 10.3 mm (.41 in).
Male individuals of the species anglerfish
Anglerfish
Anglerfishes are members of the teleost order Lophiiformes . They are bony fishes named for their characteristic mode of predation, wherein a fleshy growth from the fish's head acts as a lure; this is considered analogous to angling.Some anglerfishes are pelagic , while others are benthic...
Photocorynus spiniceps
Photocorynus spiniceps
Photocorynus spiniceps is a species of anglerfish in the family Linophrynidae. It is in the monotypic genus Photocorynus.The known mature male individuals are 6.2–7.3 millimeters , smaller than any other mature fish and vertebrate; the females, however, reach a significantly larger size of up...
have been documented to be 6.2-7.3 mm at maturity, and thus claimed to be a smaller species. However, these survive only by sexual parasitism
Parasitism
Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the other, the host. Traditionally parasite referred to organisms with lifestages that needed more than one host . These are now called macroparasites...
, and the female individuals reach the significantly larger size of 50.5 mm.
Habitat and conservation
Paedocypris progenetica lives in the dark colored peat swamps of the IndonesiaIndonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
n island of Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
.
Paedocypris micromegethes lives in the peat swamps of Sarawak
Sarawak
Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which...
(Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
). Their small size helps them to survive through extreme droughts, as they can live in small remaining puddles of acid water (pH as low as 2.9, at least 100 times more acidic than rainwater). Their habitat is threatened by forest fires, logging and plantations.