False gharial eggs have a soft inner membrane and harder, calcified shell. Crocodilian sex is determined by temperature rather than genetics. Incubation lasts approximately 90 days and young resemble small adults upon hatching. Hatchlings are equipped with an “egg tooth”, a pointed structure on the end of the snout that allows the hatchling to slice through the egg shell; this recedes a few weeks after hatching.
Development - Life Cycle: temperature sex determination; indeterminate growth
Adult false gharials are usually safe from predators due to their large size. Eggs and hatchlings preyed upon by Wild pigs (Sus scrofa) and larger reptiles, such as monitor lizards. Eggs may be collected and consumed by humans as well. In captivity, hatchlings have been killed by termites and ants before emerging from the nest mound.
Known Predators:
False gharials are large crocodilians characterized by a long, narrow snout snout filled with 76-84 sharp pointed teeth, similar to that of gharials (Gavialis gangeticus), from which false gharials get their common name. False gharials have a streamlined body and muscular tail, eyes and nostrils on top of the head, and a palatal valve that prevents water from entering the throat while underwater. They are known to grow to 4-5 m in length and may grow even larger. There are records of captive adults weighing from 93-201 kg. Both adults and juveniles have dark, sometimes chocolate brown coloration, with black banding on the tail and body and dark patches on the jaws. The belly is cream-colored or white. Males are longer and heavier than females.
Range mass: 93 to 210 kg.
Range length: 4 to 5 m.
Sexual Dimorphism: male larger
Other Physical Features: ectothermic ; bilateral symmetry
False gharials are long-lived animals with an estimated lifespan in the wild of 60 to 80 years, similar to that of other crocodilians. Reports show that captive specimens have a shorter lifespan.
Typical lifespan
Status: wild: 60 to 80 years.
False gharials are found in a variety of habitats throughout their range, including lowland freshwater swamp forests, flooded forests, peat swamps, lakes, and blackwater streams and rivers. They are also found on the fringes of rainforests near slow-moving rivers. Their preferred habitats are peat swamp areas with low elevation and acidic, slow-moving muddy water; they are also found in secondary forest habitat, characterized by more defined river channels and banks, higher pH and elevation, and a lack of peat mounds. This species needs terrestrial areas for basking and nesting.
Range elevation: 0 to 20 m.
Range depth: 0.30 to 1.10 m.
Habitat Regions: tropical ; terrestrial ; freshwater
Terrestrial Biomes: forest ; rainforest
Aquatic Biomes: lakes and ponds; rivers and streams; temporary pools
Wetlands: marsh ; swamp ; bog
Other Habitat Features: riparian
False gharials are freshwater crocodiles that are found throughout Indonesia (including Kalimantan, eastern Sumatra, western Java, and western Borneo), parts of Malaysia (including Peninsular Malaysia and Sarawak), and Brunei. There have been unconfirmed reports of false gharials in Vietnam and Sulawesi, Indonesia. They are assumed to be extirpated in southern Thailand, where they have not been seen since the 1970s. False gharial populations are isolated and occur in low densities throughout their range. The largest known populations are in Sumatra and Kalimantan, with smaller established populations in Malaysia. The highest density population of false gharials is in Tanjung Puting National Park in Kalimantan.
Biogeographic Regions: oriental (Native )
False gharials are opportunistic carnivores. They have been reported to grab monkeys (Crab-eating macaques (Macaca fascicularis) and other Macaca sp.) from river banks, submerging and drowning their prey or beating it against the bank. Other prey items include wild pigs, mouse deer, dogs, otters, fish, birds, turtles, snakes, monitor lizards, and aquatic and terrestrial invertebrates.
Animal Foods: birds; mammals; reptiles; fish; insects; terrestrial non-insect arthropods; aquatic crustaceans
Primary Diet: carnivore (Eats terrestrial vertebrates, Piscivore )
The role of false gharials in their ecosystem is not completely understood due to a lack of study in the wild. They are large predators, preying on a variety of animals and keeping their populations in check. Their distribution overlaps with that of Siamese crocodiles (Crocodylus siamensis) and saltwater crocodiles (Crocodylus porosus), and it is not known how much competition for resources there is amongst these species.
Commensal/Parasitic Species:
False gharials were once hunted for their skins, but their skins are not currently considered commercially valuable. In the Mesangat area, their eggs are collected for use in traditional medicine. There is a good deal of research being done to learn more about the roles these animals play in their environments, as well as to determine whether they should be placed in the family Crocodylidae or the family Gavialidae.
Positive Impacts: body parts are source of valuable material; source of medicine or drug ; research and education
False gharials are not considered to be a threat to humans. There has been only one documented case of an attack on a human, and one documented attack on a cow in eastern Kalimantan.
Negative Impacts: injures humans (bites or stings)
Since the 1890s, sightings and captures of wild specimens have been rare, and it has become increasingly difficult for researchers to locate any individuals for study. Populations, which tend to be very small, are restricted to small patches of swamp or forest. There has been a significant decline in the density of populations since the 1940s. In 2000 this species was assessed by the Crocodile Specialist Group and reported as endangered, with an estimate of less than 2,500 individuals remaining in the wild. More surveys must be conducted to determine the number of individuals remaining before a conservation plan can be developed. The Crocodile Specialist Group Tomistoma Task Force (CSG-TTF) has conducted fundraising for field research and international awareness, and produced reports on conservation priorities and captive breeding. False gharials are threatened by many factors including habitat loss through forest fires, drainage of wetlands, logging, agriculture development, slash and burn agriculture, and dam building. These activities have reduced this species' range in Sumatra by 30-40%. False gharials are now legally protected throughout their entire range, but enforcement of laws has been insufficient to maintain stable populations and breeding habitat. Trade of the species is also prohibited by law, but not well enforced.
US Federal List: endangered; no special status
CITES: appendix i
State of Michigan List: no special status
Communication among false gharials has not been observed in the wild. From observed mating behaviors, it can be assumed that they communicate visually, tactilely and through olfaction. Although most crocodilians use a variety of calls to communicate with their own species and to other animals, these have not been recorded for false gharials and, in fact, their mating has been observed to be silent, rather than accompanied by calls. All crocodilians possess integumentary sense organs located in the skin and covering much of the animal’s body including the body, tail, cloaca and inner surfaces of the legs, as well as on the head and jaws. These are likely used to detect changes in pressure caused by touch or the movement of prey in water; this sense is likely used for hunting in murky water.
Communication Channels: visual ; tactile ; acoustic
Other Communication Modes: vibrations
Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical
There is debate over this species’ taxonomic classification. False gharials are currently listed included in the family Crocodylidae based on fossil evidence and morphological similarities to extant crocodiles. Other data, including biochemical, immunological and molecular characters suggest a closer relationship to the family Gavialidae. Studies of nuclear genes suggest the grouping of tomistomine and gavialine crocodilians into one taxon, which would comprise a sister group to the Crocodylidae. Other crocodilian researchers suggest considering Tomistominae and Gavialinae as sister taxa.
Very little is known about the natural mating behaviors of false gharials; most details are from captive breeding programs, with a few acocunts from the wild. Courtship behavior and nesting appear to take place during the rainy season in both cases. Males approach females in the water, swimming around them. In some cases, this is accompanied by both animals hitting each other with their tails, in others copulation proceeds immediately. The male mounts the female, wrapping his tail around and under hers. Copulation occurrs once a day for several days to a week, and is accompanied by a strong odor. One captive breeding program in Malaysia had success housing a group of 3 males and 1 female. The female chose the largest male and appeared to stay near him during the courting period. When 2 females were kept in the same enclosure with the males, no mating occurred and it is theorized that females living in close proximity may suppress breeding in one another.
Mating System: monogamous
False gharials are mound-nesting crocodilians that lay very large eggs (records up to 9.5 cm long and 6.2 cm wide), with a total mass approximately double that of any other species (eggs may weigh up to 155 gm each). Mounds are usually constructed on land at the shady base of a tree near water, using sand and vegetation including peat, twigs, tree seeds, and dried leaves. Females have been observed beginning nest building a month or more after copulation and laying a clutch of 20-60 eggs 1-2 weeks after beginning to nest. After eggs are laid, more vegetation is added to the top of the nest by the female. Mounds typically measure 45-60 cm high and 90-110 cm in diameter. Eggs are laid just above ground level and the temperature within the nest fluctuates depending on the environment and rainfall (records in captivity of 26°C-32°C). Eggs hatch after 90-100 days. Captive breeding initiatives have shown that abundant vegetation improves the chances of breeding because it provides more cover and nesting material for the female. Both sexes reach sexual maturity at around 20 years of age (females measuring 2.5-3 m in length).
Breeding interval: False gharials breed twice yearly.
Breeding season: False gharial breeding occurs during the wet seasons: November-February and April-June.
Range number of offspring: 20 to 60.
Range gestation period: 90 to 115 days.
Average age at sexual or reproductive maturity (female): 20 years.
Average age at sexual or reproductive maturity (male): 20 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; oviparous
Males exhibit no parental investment beyond fertilization. Females have occasionally been observed sitting on top of nest mounds or defending them by stomping the ground, but more often flee the nest if approached. There is evidence that females may help to excavate nests before or during hatching. but they have not been observed helping hatchlings to the water as some crocodilians do. No parental investment beyond this has been observed.
Parental Investment: female parental care ; pre-fertilization (Provisioning); pre-hatching/birth (Protecting: Female)
The false gharial (Tomistoma schlegelii), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It is listed as Vulnerable on the IUCN Red List, as the global population is estimated at around 2,500 to 10,000 mature individuals.[2]
The specific name schlegelii honors Hermann Schlegel.[3][4]
The scientific name Crocodilus (Gavialis) schlegelii was proposed by Salomon Müller in 1838 who described a specimen collected in Borneo.[5] In 1846, he proposed to use the name Tomistoma schlegelii, if it needs to be placed in a distinct genus.[6]
The genus Tomistoma potentially also contains several extinct species like T. cairense, T. lusitanicum, T. taiwanicus, and T. coppensi. However, these species may need to be reclassified to different genera as evidence suggests they may be paraphyletic.[7][8]
The false gharial's snout broadens considerably towards the base and so is more similar to those of true crocodiles than to the gharial (Gavialis gangeticus), whose osteology indicated a distinct lineage from all other living crocodilians.[9] However, although more morphologically similar to Crocodylidae based on skeletal features, recent molecular studies using DNA sequencing consistently indicate that the false gharial and by inference other related extinct forms traditionally viewed as belonging to the crocodylian subfamily Tomistominae actually belong to Gavialoidea and Gavialidae.[10][11][12][13][14][15][7][16]
Fossils of extinct Tomistoma species have been found in deposits of Paleogene, Neogene, and Quaternary ages in Taiwan, Uganda, Italy, Portugal, Egypt and India, but nearly all of them are likely to be distinct genera due to older age compared to the false gharial.[17]
The below cladogram of the major living crocodile groups is based on molecular studies and shows the false gharial's close relationships:[11][14][15][7][16]
Crocodilia Alligatoridae Caimaninae Alligatorinae Longirostres Crocodylidae GavialidaeTomistoma 
The following cladogram shows the false gharial's placement within the Gavialidae; it is based on a tip dating study, for which morphological, DNA sequencing and stratigraphic data were analysed:[7]
Gavialoidea GavialidaeFalse gharial
(crown group) (stem-based group)
The false gharial is dark reddish-brown above with dark brown or black spots and cross-bands on the back and tail. Ventrals are grayish-white, with some lateral dark mottling. Juveniles are mottled with black on the sides of the jaws, body, and tail. The smooth and unornamented snout is extremely long and slender, parallel sided, with a length of 3.0 to 3.5 times the width at the base. All teeth are long and needle-like, interlocking on the insides of the jaws, and are individually socketed. The dorsal scales are broad at midbody and extend onto the sides of the body. The digits are webbed at the base. Integumentary sensory organs are present on the head and body scalation. Scales behind the head are frequently a slightly enlarged single pair. Some individuals bear a number of adjoining small keeled scales. Scalation is divided medially by soft granular skin. Three transverse rows of two enlarged nuchal scales are continuous with the dorsal scales, which consist of 22 transverse rows of six to eight scales, are broad at midbody and extend onto the sides of the body. Nuchal and dorsal rows equals a total of 22 to 23 rows. It has 18 double-crested caudal whorls and 17 single-crested caudal whorls. The flanks have one or two longitudinal rows of six to eight very enlarged scales on each side.[18]
The false gharial has one of the slimmest snouts of any living crocodilian, comparable to that of the slender-snouted crocodile and the freshwater crocodile in slenderness; only that of the gharial is noticeably slimmer.[9] Three mature males kept in captivity measured 3.6 to 3.9 m (12 to 13 ft) and weighed 190 to 210 kg (420 to 460 lb), while a female measured 3.27 m (10.7 ft) and weighed 93 kg (205 lb).[19] Females have been recorded at lengths of up to 4 m (13 ft).[20] Males can grow up to 5 m (16 ft) in length and weigh up to 590 kg (1,300 lb).[21][22] The false gharial apparently has the largest skull of any extant crocodilian, in part because of the great length of the slender snout. Out of the eight longest crocodilian skulls from existing species that could be found in museums around the world, six of these belonged to false gharials. The longest crocodilian skull belonging to an extant species was of this species and measured 84 cm (33 in) in length, with a mandibular length of 104 cm (41 in). Most of the owners of these enormous skulls had no confirmed (or even anecdotal) total measurements for the animals, but based on the known skull-to-total length ratio for the species they would measure approximately 5.5 to 6.1 m (18 to 20 ft) in length.[23]
Three individuals ranging from 2.9 to 4.05 m (9 ft 6 in to 13 ft 3 in) in length and weighing from 79 to 255 kg (174 to 562 lb) had a bite force of 1,704–6,450 N (383–1,450 lbf).[24]
False gharials are native to Peninsular Malaysia, Sarawak, and Indonesia (Sumatra, and Borneo), but were extirpated in Singapore, Vietnam, and Thailand. It is unclear if they remain in Java. Apart from rivers, they inhabit swamps and lakes.[2] The species is almost entirely found today in peat swamps and lowland swamp forests.[25] In the 1990s, information and sightings were available from 39 localities in 10 different river drainages, along with the remote river systems of Borneo.
Prior to the 1950s, Tomistoma occurred in freshwater ecosystems along the entire length of Sumatra east of the Barisan Mountains. The current distribution in eastern Sumatra has been reduced by 30-40% due to hunting, logging, fires, and agriculture.[26]
Until recently, very little was known about the diet or behaviour of the false gharial in the wild. Details are slowly being revealed. In the past, the false gharial was thought to have a diet of only fish and very small vertebrates, but more recent evidence indicates that it has a generalist diet despite its narrow snout. In addition to fish and smaller aquatic animals, mature adults prey on larger vertebrates, including proboscis monkeys, long-tailed macaques, deer, water birds, and reptiles.[27] There is an eyewitness account of a false gharial attacking a cow in East Kalimantan.[25]
The false gharial may be considered an ecological equivalent to Neotropical crocodiles such as the Orinoco and American crocodiles, which both have slender snouts but a broad diet.[9]
False gharials are mound-nesters. Females lay small clutches of 13 to 35 eggs per nest, and appear to produce the largest eggs of extant crocodilians. Sexual maturity in females appears to be attained around 2.5 to 3 m (8.2 to 9.8 ft), which is large compared to other crocodilians.[26]
It is not known when they breed in the wild or when the nesting season is. Once the eggs are laid, and construction of the mound is completed, the female abandons her nest. Unlike most other crocodilians, the young receive no parental care and are at risk of being eaten by predators, such as mongooses, tigers, leopards, and wild dogs. The young hatch after 90 days and are left to fend for themselves.
In 2008, a 4-m female false gharial attacked and ate a fisherman in central Kalimantan; his remains were found in the gharial's stomach. This was the first verified fatal human attack by a false gharial.[27] However, by 2012, at least two more verified fatal attacks on humans by false gharials had occurred indicating perhaps an increase of human-false gharial conflict possibly correlated to the decline of habitat, habitat quality, and natural prey numbers.[28]
The false gharial is threatened with extinction throughout most of its range due to the drainage of its freshwater swamplands and clearance of surrounding rainforests. The species is also hunted frequently for its skin and meat, and the eggs are often harvested for human consumption.[27]
The false gharial is listed on CITES Appendix I.[2] Currently population surveys indicate that while the false gharial is not for the most extirpated from areas it used to inhabit, the distribution of individuals is much more spotty than the previously more connective distribution, putting the animals at risk of genetic isolation.[29] In large part, the isolation of false gharials is due to extremely extensive habitat destruction and disturbance within the species' area of distribution, few areas outside of legally protected areas are likely to bear viable breeding populations.[30]
Steps have been taken by the Malaysian and Indonesian governments to prevent its extinction in the wild. There are reports of some populations rebounding in Indonesia, yet with this slight recovery, mostly irrational fears of attacks have surfaced amongst the local human population.[27] Yayasan Ulin (The Ironwood Foundation) is currently attempting to manage a wetland area in East Kalimantan, which is known to contain the false gharials.[31]
_white_background.jpg){kind=small}
{{cite book}}: CS1 maint: multiple names: authors list (link) {{cite book}}: CS1 maint: multiple names: authors list (link) {{cite journal}}: CS1 maint: multiple names: authors list (link) {{cite book}}: CS1 maint: multiple names: authors list (link) The false gharial (Tomistoma schlegelii), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It is listed as Vulnerable on the IUCN Red List, as the global population is estimated at around 2,500 to 10,000 mature individuals.
The specific name schlegelii honors Hermann Schlegel.
