Licorice gouramis

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Licorice gouramis
Mating licorice gourami male (Parosphromenus phoenicurus)

Mating licorice gourami male ( Parosphromenus phoenicurus )

Systematics
Perch relatives (Percomorphaceae)
Order : Climbing fish species (Anabantiformes)
Subordination : Labyrinth fish (Anabantoidei)
Family : Osphronemidae
Subfamily : Large Flosser (Macropodusinae)
Genre : Licorice gouramis
Scientific name
Parosphromenus
Bleeker , 1877

The Parosphromenus the genus Parosphromenus is relatively small permanent representatives of the suborder labyrinth fish (Anabantoidei) within the perch family (Percomorphaceae), their distribution in the freshwater and peat swamps of Southeast Asia, more precisely in the south of the Malay Peninsula , on Borneo and Sumatra is located . The genus was established by Pieter Bleeker in 1877 after he had already described the type species Parosphromenus deissneri as Osphromenus deissneri in 1859 . It owes its German name to the very attractive and colorful courtship coloring of the male individuals. Due to their hidden way of life and extreme habitats, their history of discovery is relatively young and most likely not yet complete. Today, all licorice gourami species are “highly threatened in their continued existence as a result of the rapid destruction of the jungle in Southeast Asia”.

Distribution area and habitats

Schwarzwasserbach in West Malaysia - a typical habitat for licorice gourami species.

So far, licorice gouramis from southern Thailand , western Malaysia, Borneo and Sumatra have been scientifically documented. They come there exclusively in the fresh water of the coastal lowland rainforests and peat swamps, z. B. the peat bog forests of Borneo . In the biotopes, the soils consist mostly of plant detritus and peat, which like a sponge stores water in the rainy season and then releases it again during the dry season.

The slowly rotting plant material enriches the water with various humic substances , giving it its characteristic properties. The habitats, mostly slow-flowing streams, have very soft and acidic water, which is called black water because of its typical dark, tea-brown color and is "crystal clear". The pH value in such waters is usually between 4.5 and 5.5, but in exceptional cases even 3.4 with a simultaneous lack of minerals: values ​​between 6 μS / cm and 75 μS / cm are usually measured for electrical conductivity .

With a few exceptions, licorice gouramis are stenotopic blackwater species that are adapted to these extreme conditions and can therefore serve as a bio-indicator for the classification of water bodies. Above all, licorice gourami's eggs need this “hostile environment” to develop, as the low pH values ​​on the other hand guarantee “the lowest possible germ load”. These peat swamps are among the most threatened biotopes in Southeast Asia, v. a. the Malay Peninsula. As early as 1994, Ng et al. Point out that many of the black water swamps of Singapore and West Malaysia examined in the second half of the 20th century were converted into rice, pineapple and mostly oil palm plantations and that the protection of the remaining biotopes is of crucial importance was to prevent the extinction of many species, including those of economic value.

nutrition

Like most labyrinth fish, licorice gouramis feed mainly on zooplankton such as small crabs , mollusks , insects and their larvae . It seems v. a. the larvae of freshwater shrimp play a major role, which are often found in large numbers and in different sizes in the biotopes.

Characteristics and gender dimorphism

Female licorice gourami in simple stripes - Parosphromenus phoenicurus .
Colored males while showing each other - Parosphromenus phoenicurus .

All licorice gourami species show in normal color, more or less pronounced, a characteristic longitudinal stripe pattern on the sides of the body, consisting of two dark brown to black longitudinal stripes on a light brown or beige background from the snout, often "also through the eye" to the base of the caudal fin. "The term Licorice gourami, ie liquorice gourami, describes the body drawing quite clearly". The genus has a pronounced gender dichromatism (→ sexual dimorphism ). While males, especially in splendid colors, have high-contrast color patterns, often in the form of a banding in the unpaired fins, with iridescent elements, the females are generally rather inconspicuous and only rarely show matt speckles of color in the otherwise transparent fins. In addition, the females of most species are so similar that an identification can only be made on the basis of male individuals in splendid colors. For this, especially in the case of representatives of the very homogeneous " P. harveyi group" (see below), the named colored bands, as well as the colors of the pelvic fins and their filaments, play a decisive role.

Another characteristic of the licorice gourami types are the small maximum total lengths achieved. P. parvulus, for example, represent "with a maximum total length of 27mm [...] the smallest currently known labyrinth fish". Most species are between 3.5 cm and 4.5 cm in size. P. quindecim and P. deissneri , as the largest representatives of the genus, reach maximum overall lengths of 5.0 cm.

Another special feature are the multi-rayed, and therefore relatively long dorsal and anal fins. Depending on the species, the numbers of hard rays in the dorsal and anal fins vary between 9 and 11 or between 7 and 9 in P. ornaticauda, between 17 and 18 or between 13 and 16 in P. paludicola This fin structure gives the impression that it is a closed, circumferential fin border, whereby the continuous colored banding that occurs in some species underlines this effect (→ see Fig. P. phoenicurus ). In contrast to the males, the females show less strongly extended fins and appear more compact overall.

Behavior and reproduction

Licorice gouramis are calm, shy fish that hardly ever stay in open water, but mostly hidden in the root thicket, in plant cushions or in the bank vegetation hanging in the water, as well as under overhangs.

They can also be found near the ground between fallen leaves and in the deeper water layers of 1.0m-1.5m. The latter is surprising, since most of the other representatives of the labyrinth fish tend to live more surface-oriented, as they have to breathe atmospheric air. This is to be seen as an adaptation to mostly standing and during the dry season very warm and therefore oxygen-poor water. Although licorice gouramis also have such an additional respiratory organ, they seem to almost completely dispense with labyrinth breathing. It can therefore be assumed that the water in the corresponding biotopes contains enough oxygen so that “the gill breathing is obviously sufficient”. Another special feature are the different mood colors that deviate from the normal color and "can often change in a few seconds".

Courtship and brood care

Courting pair of Parosphromenus phoenicurus - the female loses its stripes.
Parosphromenus harveyi - courtship male in typical "upside down position".

Furthermore, all licorice gourami species show interesting courtship and brood care behavior. During the courtship season, which for many species most likely begins with the onset of monsoon rain in November and the associated thinning of the water that is concentrated during the dry season, the males occupy small, cave-like shelters in the fallen leaves or root network of the bank vegetation and build a rudimentary foam nest on the cave ceiling. With some species it can happen that, if at all, a small foam nest is only built after spawning, e.g. B. P. tweediei . The only exception with a larger foam nest is P. filamentosus . The males now show their splendid coloration, which in many species is based on an intensification of the existing colors and contrasts (additionally dark throat and belly region). In some, however, it deviates completely from the normal coloration, e.g. B. in P. nagyi or P. parvulus . In their most contrasting and striking color, they try to lure females ready to spawn into the cave and spawn with them by showing off and performing various courtship dances. In doing so, they stretch their fins and make trembling movements with their bodies, possibly in order to generate pressure waves directed sideways in the direction of the female. Depending on the species, this is done with the head up ( P. ornaticauda, ​​P. parvulus, P. sumatranus ), in a horizontal posture (e.g. P. pahuensis ) or upside down (e.g. P. tweediei, P. deissneri ). This is an important ethological feature that can be used to clarify the relationships within the genus . (see below → Systematics) The coloring of the females during courtship differs to a considerable extent from that of the males and is different depending on the species. The stripes usually disappear and the females become uniformly light brown with slightly darkened fins (e.g. P. harveyi ) or can even adopt a darker pattern similar to the male (e.g. P. ornaticauda ). In addition, with a few exceptions, both sexes show a vertical, dark stripe through the eye during courtship, so to speak a negative of the otherwise horizontal drawing. For this purpose, Schaller coined the term “sexy-eyes”, which is used today among specialists.

Licorice clutches with eggs and larvae on the ceiling of the cave.

If a male has managed to lure a female into the cave, there are initially some false pairings in which the fish wrap around each other like a labyrinth, briefly fall into paralysis, but no eggs are yet released. After this synchronization phase, the actual mating occurs, in which the female gives off a few sinking eggs per spawning process, which are then stuck to the ceiling of the cave by both of them (Foersch found that this attachment of the eggs only occurs in water with a carbonate hardness of up to 1.4 ° dKH works, at higher values ​​the eggs fall back to the ground). Between the individual spawning phases, the male occasionally leaves the cave "to get air from the water level" while the female remains under cover. When mating is over, the female leaves the cave or is chased away by the male, probably to guard the larger area around the cave. From then on, the male takes care of the clutch of between a maximum of 25 eggs in P. ornaticauda and up to over 100 eggs in P. filamentosus, P. quindecim and P. linkei , depending on the species .

Young fish several weeks old

After approx. 2–3 days, the initially unpigmented larvae hatch, which remain in the nest for approx. 6–7 more days, first vertically and later horizontally, before they swim free. A total of 10 days after spawning the brood care of the male ends, whereby in many cases spawning takes place again before the last brood is free to swim. The juvenile fish of most species are sexually mature after approx. 9–12 months, "although they [then] have not yet reached their maximum size".

Aggressive behavior

Parosphromenus harveyi - males threatening each other - the stripes on the body fade.

The otherwise peaceful, sometimes even sociable licorice gouramis show v. a. territorial behavior during the mating season, d. H. especially the males defend the shelter they have occupied and the surrounding area against opponents. During a test of strength between two male individuals, the animals show a species-typical aggression coloration, in which in many cases the high-contrast coloration of the fins is retained or intensified while the stripes on the trunk fade. In addition, in many species the throat and abdominal region turns dark to black. In an antiparallel position and with their fins spread, the opponents begin to circle each other, which is then followed by individual, targeted rams. Most of the time the winner is determined by now at the latest and the loser searches the distance with clamped fins. Serious injuries hardly ever occur in these comment fights . Females of many species show a similar aggression coloring with an often almost streak-free body and diffuse colored fins, but the comment battles are not as pronounced in comparison to those of the males.

use

Due to their small size, licorice gouramis do not play a role in the diet of the local population. Occasionally, however, certain quantities are caught and exported via the ornamental fish trade. Ng et al would welcome such a practice in spite of the threat to the habitats, since the measured and planned catch for the ornamental fish trade is a possibility for the local population to benefit financially from the long-term protection of the peat swamps and thus their resources. Of course, this assumes that the catches have to be planned so as not to endanger the populations and that the yields really benefit the local population.

Systematics

The system within the genus has not yet been clearly clarified. This is due on the one hand to the relatively recent history of description, on the other hand to the type of descriptions, which are mostly based on the means of classical taxonomy (such as the comparison of body dimensions, fin formulas, etc.). Since many licorice gourami species are very similar or identical in this respect, ethological investigations must in any case be consulted to clarify the relationships and the delimitation of the individual species from one another. Often species differ only in tiny color details, which can only be assessed in males in splendid coloration, which is why it is absolutely necessary to have living individuals available for identification and description. In addition, genetic analyzes could complement the previous picture in the near future and thus contribute to a better understanding of the genus.

Species groups

One method of bringing the 20 scientifically described licorice gourami species into a preliminary species system is the list of species drawn up by Martin Hallmann and used in the International Labyrinth Fish Association (IGL), which includes both morphological and ethological characteristics in order to achieve the summarize individual species in groups.

The species "combines [...] features of the two major structural and behavioral types of the Prachguramis". On the one hand the slim body shape and the "head up courtship" of the males, on the other hand the body drawing and drawing of the fins similar to group C.

  • Group C: "the round-fins"

The common feature of this large group is a round caudal fin and uniform fin bands in the unpaired fins.

The males show a different, streakless (two-part) splendid color of the body.

Large and very homogeneous group in terms of body measurements, behavior and drawing. Named after the first described species.

The group is characterized by an extended caudal fin with clear filament.

Typical for this group are 1–3 dark side spots in the middle of the body and monochrome, unpaired fins with translucent, iridescent dots: "Starry sky type".

  • Group F: "The big one, with a new combination of all known drawing patterns"
  • Group G: "Types with almost no drawings with long dorsal fin and long lanceolate caudals"

In addition to these scientifically described species, many other forms are known to date, the species status of which has not yet been clarified. Most of them have either been discovered and imported directly by aquarists or have found their way into specialist aquarists through large ornamental fish importers. These forms, which cannot be clearly assigned to a species, are referred to as P. spec. referred to and usually given as an addition the name of the place where they were found or where they were found etc. (e.g. P. spec. "Sentang" ). Sumatra in particular has introduced many new forms such as “Sentang” or, which can be classified in the (C2) “ P.harveyi group”. This supports the hypothesis that the large number of species and undescribed forms of this group, which often only differ in their fin color and color details, are color or location variants of the same species, or at least some of the species already described Subspecies would have to be downgraded. Two of these previously unrecorded forms of Sumatra, namely in lover circles under P . spec. "Danau Rasau" and P . spec. Forms known "Langgam" were newly described in December 2012 by Schindler and Linke as P. gunawani and P. phoenicurus and thus received species status.

History of P. deissneri

In 1859 the Dutch ichthyologist Pieter Bleeker described the species Osphromenus deissneri on the basis of a single female of a licorice gourami from Baturussak ( Bangka Island / Indonesia) and thus classified it in the genus of the food or giant gouramis Osphronemus (Lacepede, 1801), although he used the letters m and n swapped. In 1877 he established the genus Parosphromenus with P. deissneri as a type species and kept this spelling.

Since towards the end of the 20th century many round-finned (caudal fin), obviously different species and shapes with regular bands of color in the unpaired fins were known, all of which were named P. deissneri , a revision of the genus was necessary. The ichthyologists Maurice Kottelat and Peter KL Ng first had to clarify the identity of P. deissneri . In collections on Bangka, a total of two different licorice gourami species could be detected, one of which must be that described by Bleeker as P. deissneri . One of the two species had a round caudal fin in the male sex and a continuous bluish-iridescent fin banding of the unpaired fins. The other, on the other hand, had a slightly lanceolate caudal fin with black filament and a banding that consisted of individual, oval, bluish-iridescent points. However, since the holotype deposited by Bleeker was a female, and it was already colorless, severely shrunk and damaged, identification was no longer possible using this material. In addition, there was no longer a biotope at the former site, but a small town has now emerged. It was therefore decided to re-describe the species that was found at least in the same water system near the original type locality as P. deissneri . Of all things, it was the type with filament and non-continuous banding. The other species was known from another site on the island of Bintan and was newly described as P. bintan (cf. 1, 36). The status of the many different forms, which were previously referred to as "deissneri color forms", remained unclear, and the previous designation became "wrong, as the redefinition of 'deissneri' destroyed this reference". Therefore, in 2005, four further descriptions of licorice gouramis from this group followed ( P. alfredi, P. opallios, P. rubrimontis, P. tweediei ), which "brought a certain order into the fragmentary system of this group".

Licorice gouramis in the aquarium hobby

Licorice gourami aquarium.

The licorice gourami aquaristic in Germany goes to the doctor Dr. Walther Foersch, who made detailed observations on the care and reproduction of the small labyrinth fish in the early 1970s and published them in a two-part article in DATZ . He thus created "the basis for the breeding of all Parosphromenus species" since many of the knowledge he gained applies to all licorice gourami species.

Basically one can say that the fish are comparatively sensitive and therefore “require special framework conditions and make relatively high demands on the keeper”. Nevertheless, they are loved by lovers of a. Because of their splendid courtship colors and their interesting behavior, they are happy to be kept and increased.

In his "Paro recipe", Peter Finke points out that there are four main factors that are necessary for long-term care and successful reproduction:

  1. "Healthy, sexually mature fish,
  2. a not too big, dark, calm, cave-rich aquarium,
  3. Water with as few germs as possible with a very low salt content and pH value and
  4. exclusive live feeding ”.

The fish

Care should be taken that no previously damaged fish are acquired, as it is rarely possible to bring them back into good condition.

The aquarium

A small aquarium for the extensive breeding of licorice gouramis.

In any case, the fish are not suitable for a standard brightly lit community aquarium. Small, dimly lit 12 or 25 liter aquariums are best, which are generously structured with (swimming) plants, bog wood and leaves, taking into account the shy nature of licorice gouramis . As plants with the z. Still cope T. extreme water values are mainly Java fern ( Microsorum pteropus ), water horn ferns ( Ceratopteris spec. ), Salvinia ( Salvinia sp. ) And dwarf Anubias ( Anubias barteri var. Nana ), but also various Moose z. B. Java moss ( Taxiphyllum barbieri ). The best foliage is "old beech leaves, collected dry in autumn", which can be doused with boiling water shortly before use, "so that it perishes immediately and harmful organisms are killed". If the fish are to have the opportunity to reproduce, which is a matter of course given their rarity, a small cave the size of a 35mm film can is placed in such a tank , in which the male can build his nest. In order for young fish to emerge, only one pair of a species should be used per aquarium and accompanying fish should be avoided.

The water

One possibility of water treatment: reverse osmosis system with subsequent peat treatment.

Since licorice gouramis, as specialists, are adapted to extreme habitats, the aquarium water must, if possible, orient itself to the water of the natural biotopes (→ black water) and thus be very soft, slightly acidic and enriched with various humic substances. This works best by adding (unfertilized!) Raised bog peat to a source water that is very poor in minerals (e.g. rainwater, water from a reverse osmosis system or a mixed-bed filter / ion exchanger ) and thus slightly acidified and enriched with humic substances . These humic substances play an important role in "buffering the extreme water values". A pH value of approx. 5–6 seems to be ideal, as it ensures a low bacterial load. The electrical conductivity , which provides information about the approximate mineral content of the water, is also important. In any case, it should be below 80 microsiemens / cm [μS / cm] for the desired water. Adult licorice gouramis seem to tolerate harder water temporarily, but their larvae and v. a. the eggs compel this milieu to develop.

The lining

Simple bottle for incubating Artemia nauplii from cysts .

In order to keep licorice gouramis healthy in the long term, there is no avoiding exclusive live feeding . Since licorice gouramis only react to moving food animals and are generally rather "reluctant eaters", it could happen that the aquarium water is heavily polluted by uneaten and spoiling remains of frozen food or the like, thus destroying the targeted low-germ environment. All types of live food that are not too big for the fish are suitable: all types of mosquito larvae , smaller daphnia , grindal worms ( Enchytraeus buchholzi ), smaller enchytra , Japanese water fleas ( Moina macrocopa ), artemia and v. a. Artemia nauplii , which can easily be incubated from artemia cysts in salt water. Another advantage of nauplii is that they can be used to feed both young and old animals that are in a tank. For juvenile fish, vinegar eels ( Turbatrix aceti ) and micro-worms ( Panagrellus redivivus ) can also be used. Of course, you should pay attention to a certain variety.

threat

Since almost all licorice gourami species only have a low adaptability to changes in water caused by humans such as z. B. fertilizer and pesticide input, straightening, etc., their continued existence is severely threatened by the ongoing primary forest destruction in Southeast Asia. Many of the original lowland rainforests and peat swamps, which are characterized by high biodiversity , must be agricultural monocultures , v. a. Oil palms ( Elaeis guineensis ) are giving way and former jungle streams are being transformed into canals that are supposed to quickly drain away the excess water. Palm oil companies such as SinarMas , Wilmar u. a. deliver palm oil v. a. to corporations such as Unilever and Nestlé for processing in various household products and food, but also to the EU, which imports palm oil processed into " biodiesel ".

Of course, not only the licorice gouramis and such symbolic animals as the orangutans are affected by this destruction of nature , but also the entire, unique and sometimes highly specialized fauna and flora of these habitats. Last but not least, it is also people, mainly indigenous peoples , who are not only threatened indirectly by the destruction of their living space and thus their livelihood, but also directly by violent displacement and expropriation. In order to draw attention to these human rights violations in Europe, too, representatives of indigenous tribes from Sumatra and Borneo protested in Hamburg in front of the Unilever headquarters and in Brake near Bremen, where Unilever supplier Wilmar operates a palm oil refinery. The Indonesians were supported by nature conservation organizations such as Rettet den Regenwald e. V. and Robin Wood , who with their campaigns try to influence those responsible from politics and business in order to initially persuade them to forego “palm oil from overexploitation ” and in the long term to stop further “expansion of palm oil plantations in the tropics” ".

The Parosphromenus Project

The Parosphromenus-Project is “a global conservation network” that emerged from the Paro-AG, which was founded in 2005 by Peter Finke and Martin Hallmann within the International Association for Labyrinth Fish (IGL). It was founded “in order to raise awareness of the licorice gouramis, which are highly threatened but little-known, to the attention of aquarists and the general public”. Responsible conservation aquariums are proclaimed in contrast to the current trend of consumer-oriented consumption aquariums. The project sees itself as a merging, cross-association network that tries to address "Paro friends" from the various enthusiasts' associations such as IGL, AKL / EAC, AAGB but also VDA and EATA and thus to bundle forces. In addition to its main goal of "making an effective contribution to the conservation of these fish", it pursues the increase and dissemination of knowledge about the species "and the strengthening of awareness of its threat". The project also tries to influence "biotope conservation and nature conservation in their home countries". As part of an alternative aquarium hobby that does not ignore the massive destruction of nature in Southeast Asia, but explicitly includes "the environmental and economic dimension of this hobby", it seeks contact with nature conservation organizations or tries to "relate to our everyday life in the western, industrialized world" produce by z. B. points to our indirect participation in the destruction of biodiversity, for example through the consumption of palm oil products or tropical timber. In order to achieve its declared main goal, namely "the long-term preservation of aquarium populations", the project relies on the mutual "exchange of information and fish" among the members, as well as their willingness to "voluntarily sponsor species". Furthermore, a census takes place every six months in which all members provide information about their aquarium stocks. This inventory survey, which can be viewed by all members, provides information on "the distribution and reproduction situation" of the individual species or forms and forms "the basis for the award of sponsorships". As a result, all species and many of the "varieties introduced in very small stocks" could be preserved in the aquarium stocks in the past few years.

literature

  • Peter Finke, Martin Hallmann: licorice gouramis - jewels of the jungle in nature and in the aquarium . Aqualog Verlag, Rodgau 2013, ISBN 978-3-939759-27-0 .
  • Horst Linke: Labyrinth fish - color in the aquarium . Tetra Verlag, Münster 1998, ISBN 3-89745-120-4 .
  • Helmut Pinter: Labyrinth fish, pike heads and snakehead fish . Ulmer Verlag, Stuttgart 1984, ISBN 3-8001-7093-0 .
  • Jürgen Schmidt: Guramis and thread fish . Bede Verlag, Ruhmannsfelden 1998, ISBN 3-931792-48-X .
  • Jörg Vierke: Labyrinth fish and related species . Pfriem Verlag, Wuppertal-Elberfeld 1978, ISBN 3-921677-08-4 .

Web links

Commons : Licorice gouramis ( Parosphromenus )  - Collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d e P. KL Ng, M. Kottelat: Osphromenus deissneri Bleeker, 1859 (currently Parosphromenus deissneri Osteichtyes, Osphronemidae): proposed replacement of holotype by a neotype. (Case 3071). In: Bulletin of Zoological Nomenclature. 55 (3), 1998, pp. 155-158.
  2. ↑ a b c P. KL Ng: Blackwater fish from North Elangor (Malay Peninsula). In: The aquarium and terrarium magazine. 46, 1993, pp. 112-117.
  3. ↑ a b c The survival of licorice gouramis is not certain. ( Memento of the original from February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  4. ↑ a b c d e M. Kottelat, PKL Ng: Diagnoses of six new species of Parosphromenus (Teleostei: Osphronemidae) from Malay Peninsula and Borneo, with notes on other species. In: The Raffles Bulletin of Zoology . Supplement No. 13, 2005, pp. 101-113.
  5. ↑ a b c d e f g h i j P. Finke: My Paro recipe - about keeping and breeding licorice gouramis. In: The Macropod. 28 (7/8), 2006, pp. 115-126.
  6. ↑ a b c d P. KL Ng, JB Tay, KK P Lim: Diversity and conservation of blackwater fishes in Peninsular Malaysia, particularly in North Selangor peat swamp forest. In: Hydrobiologica. 285, 1994, pp. 203-218.
  7. ↑ a b c d H. Linke: Labyrinth fish - color in the aquarium. 5th completely revised edition. Tetra-Verlag, Münster 1998, pp. 9-10 and pp. 120-141.
  8. ↑ a b c What you need to know about the habitats of licorice gouramis. ( Memento of the original from February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  9. ↑ a b c d e f g h i j k Labyrinth wiki of the IGL with species portraits ( Memento of the original from February 3, 2014 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. on: igl-home.de , accessed on March 1, 2012. @1@ 2Template: Webachiv / IABot / www.igl-home.de
  10. ↑ a b c d e f g h i M. Hallmann: licorice gouramis a complex topic. Part 3: Representatives of the Parosphromenus harveyi group. In: The Macropod. 33 (3) 2011, pp. 83-87.
  11. ↑ J. Vierke: A new labyrinth fish from Borneo - Parosphromenus parvulus nov. spec. In: The aquarium. 120, 1979, pp. 247-250.
  12. ↑ a b c The species currently recognized by science. ( Memento of the original from February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  13. ^ A b M. Kottelat: Notes on the taxonomy and distribution of some Western Indonesian freshwater fishes, with diagnoses of a new genus and six new species (Pisces: Cyprinidae, Belontiidae, and Chaudhuriidae). In: Ichthyological Exploration of Freshwaters. 2, 1991, pp. 273-287.
  14. ↑ MWF Tweedei: Notes on Malayan fresh-water fishes. Part 3: The ananbantoid fishes. Part 4: Some new and interesting records. Part 5: Malay names. In: Bulletin of the Raffles Museum. 24, 1952, pp. 63-95.
  15. ↑ a b c d e f g h W. Foersch: Observations during the breeding of Parosphromenus deissneri. In: The aquarium and terrarium magazine. 27 (10) 1974, pp. 338-343 and 27 (11) 1974, pp. 372-374.
  16. ↑ a b c d e D. Schaller: Parosphromenus nagyi spec. nov., a new licorice gourami from Malaysia (preliminary communication). In: The aquarium and terrarium magazine. 38, 1985, pp. 301-303.
  17. ↑ a b c The behavior of the licorice gouramis is a story in itself. ( Memento of the original from February 20, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  18. ↑ The genus “Parosphromenus” Bleeker 1877. ( Memento of the original dated February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  19. ↑ a b c J. Vierke: Parosphromenus filamentosus n.sp. from SO Borneo (Pisces: Belontiidae). In: Senckenbergiana Biologica. 61, 1981, pp. 363-367.
  20. ↑ Jörg Vierke: Observations on the reproductive and learning behavior of the dark swamp licorice gouramis. ( Memento of the original from February 7, 2012 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. on: fischhaben.de , accessed on March 1, 2012. @1@ 2Template: Webachiv / IABot / www.fischhaben.de
  21. ↑ J. Vierke: Beautiful and easy to care for: The fine thread dwarf gourami from Borneo - care and breeding of Parosphromenus filamentosus . In: Aquariums Magazin. 5, 1982, pp. 300-305.
  22. ↑ What you should know about these fish. ( Memento of the original from February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  23. ↑ a b c breeding. on: guenter-kopic.de , accessed on March 1, 2012. (Günter Kopic's pages on licorice gourami breeding)
  24. ↑ a b licorice gouramis. ( Memento of the original from March 16, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. on: fischreisen.de Pay special attention to the video for P. spec. Langgam ; Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.fischreisen.de
  25. ↑ Taxonomy ( Memento of the original dated February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  26. ↑ a b c d e f g M. Hallmann: licorice gouramis - a complex topic. Part 1, In: The Macropod. 30 (3) 2008, pp. 95-99.
  27. ↑ a b Parosphromenus sumatranus. ( Memento of the original from January 4, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  28. ^ Parosphromenus filamentosus. ( Memento of the original from January 4, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  29. ^ Parosphromenus deissneri. ( Memento of the original from January 4, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  30. ↑ Science is lagging behind: Other forms that are already known. ( Memento of the original from February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  31. ↑ H. Linke: New licorice gouramis from Indonesia. In: Aquarium Live. 4, 2008, pp. 12-17 and 5, 2008, pp. 62-65.
  32. ^ I. Schindler, H. Linke: Two new species of the genus Parosphromenus (Teleostei: Osphronemidae) from Sumatra. In: Vertebrate Zoology. 62 (3), 2012, pp. 399-406. (on-line)
  33. ↑ P. Bleeker: Negende bijdrage tot de kennis of the vischfauna van Bangka. In: Natuurkundig tijdschrift voor Nederlandsch-Indië. 18, 1859, pp. 359-378.
  34. ↑ M. Kottelat, PKL Ng: Parosphromenus bintan, a new belontiid fish from Bintan and Bangka islands, Indonesia, with redescription of P. deissneri Bleeker, 1859 (Teleostei: Osphronemidae). In: Ichthyological Exploration of Freshwaters. 8 (3), 1998, pp. 263-272.
  35. ^ J. Geck: The licorice gouramis. In: The aquarium and terrarium magazine. 45 (4), 1992, pp. 216-219.
  36. ↑ P. Finke: Praise of the colorful dwarfs - Six reasons why licorice gouramis are (almost) ideal aquarium fish for me. In: The Macropod. 30 (1), 2008, pp. 7-11.
  37. ↑ Food ( Memento of the original from February 20, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  38. ↑ a b How Unilever palm oil suppliers are burning up Borneo. ( Memento of the original from February 2, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: greenpeace.org , accessed March 1, 2012. @1@ 2Template: Webachiv / IABot / www.greenpeace.org
  39. ^ Wilmar International , accessed March 1, 2012.
  40. ↑ a b Unilever admits violations of the law and violence at palm oil suppliers. from regenwald.org , accessed March 1, 2012.
  41. ↑ Palm Oil - News ( Memento of the original from February 19, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from regenwald.org , accessed March 1, 2012. @1@ 2Template: Webachiv / IABot / www.regenwald.org
  42. ↑ a b c d P. Finke: The Parosphromenus project - a globally operating conservation network. In: Amazon. 8 (2) 2012, pp. 36-41.
  43. ↑ a b How the Parosphromenus Project came about. ( Memento of the original from September 24, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  44. ↑ a b What the Parosphromenus Project is about. ( Memento of the original from April 7, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  45. ↑ What is the Parosphromenus Project? ( Memento of the original from February 18, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  46. ↑ a b The participants are the most important part of the Parosphromenus Project! ( Memento of the original from April 7, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org
  47. ↑ a b c Regular inventories are the basis of all maintenance work. ( Memento of the original from September 24, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. from: parosphromenus-project.org , Retrieved March 1, 2012. @1@ 2Template: Webachiv / IABot / www.parosphromenus-project.org