Elongate Mudskipper (Pseudapocryptes elongatus)

Elongate Mudskipper (Pseudapocryptes elongatus)

An adult Elongate Mudskipper found in a back mangrove creek.

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Pseudapocryptes elongatus
Common Name(s): Elongate Mudskipper

Presence in Singapore: Native
Habitat: Coastal: Mangrove forest creeks down to mudflats.
Conservation status: Vulnerable (Red Data Book 3)

This is one of the lesser encountered mudskipper species in Singapore. This is a long species as evident by its common name, reaching up to a maximum length of 24cm. The Elongate Mudskipper has well-proportioned fins which aren't flashy like its relatives. Both juveniles and adults have varying levels of slanted stripes on a greenish-brown/grey body. While they have been recorded living down in the mudflats, sightings of them in Singapore seem to be limited to back mangrove creeks such as in Pulau Ubin, where they're most often seen. In 2024, juveniles of the Elongate Mudskipper were found to be living in the open breakwater of Marina East by us, where they have burrows in the muddy pools present. With adults being sighted before in the same area, it is a surprising habitat considering their preferences but they seem to be thriving.

Elongate Mudskippers are omnivorous, feeding on algae and small invertebrates such as worms. As mentioned in (Polgar, 2013), they have a few feeding styles such as sifting (like the Bearded Mudskipper), scraping (like the Boddart's Blue-spotted Mudskipper) and pump-suspension feeding where they inhale suspended particles. This species is the most aquatic of all mudskippers seen reliably in Singapore, preferring to sit under water with only its eyes breaching the surface. 

A juvenile Elongate Mudskipper from Marina East. (Photograph by: Jiayuan Lin)

A juvenile Elongate Mudskipper which without Jiayuan's side shot, it might've been impossible to ID.

Check out this video: https://www.youtube.com/watch?v=SfArKeBzsVE&ab_channel=SGfishesabovewater



References

• FishBase. Pseudapocryptes elongatus Cuvier, 1816 – (Mudskipper). Retrieved from https://fishbase.se/summary/Pseudapocryptes-elongatus
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.
• Ong JXL, Tay JX & JY Lin (2025) Biodiversity Record: Elongate mudskippers, Pseudapocryptes elongatus, at Marina East. Nature in Singapore, 18: e2025010. DOI: 10.26107/NIS-2025-0010
• Polgar, G. Gobiidae: Oxudercinae – Pseudapocryptes elongatus Cuvier, 1816. Retrieved from http://www.mudskipper.it/SpeciesPages/elon.html 

Bearded Mudskipper (Scartelaos histophorus)

Bearded Mudskipper (Scartelaos histophorus)

A mated pair of Bearded Mudskippers.

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Scartelaos histophorus
Common Name(s): Bearded Mudskipper, Walking Goby

Presence in Singapore: Native
Habitat: Coastal: Open mudflats and creek banks.
Conservation status: Vulnerable (Red Data Book 3)

One of Singapore's lesser encountered mudskippers due to its habitat preference. The Bearded Mudskipper is easily recognized by its elongated body shape which can reach up to 14cm in length. It is overall grey with sparse black dots. The first dorsal fin is very tall and it is raised in territorial displays as with all mudskippers. The unique feature about this species is that it has barbels below its head, resulting in the common name.

The Bearded Mudskipper is mostly encountered on open mudflats where the mud is sticky and one can sink in it to varying levels. They can also be encountered further upstream along creek banks but larger individuals are further out to sea. Similar to the Boddart's Blue-spotted Mudskipper, they only appear during low tide and hide in their burrows where there is an air pocket during high tide. This species is omnivorous and it feeds by sifting through the mud, running it through its gills and expelling the sediment. It feeds on tiny organisms such as algae, crustaceans and worms.

They are known for their impressive displays where the male leaps into the air but keeps its tail on the ground, making it seem like it is standing up! If a female is interested, they share a burrow together. It appears that juveniles are not as elongated and have the normal mudskipper proportions.

A Bearded Mudskipper sifting through the mud for food.

A small Bearded Mudskipper that has just emerged from its burrow.

YouTube videos

• Passive behaviour: https://www.youtube.com/watch?v=BWEUVAqJFzw&ab_channel=SGfishesabovewater
• Burrow emergence: https://www.youtube.com/watch?v=9MdIDaMvDUs&ab_channel=SGfishesabovewater

References

• FishBase. Scartelaos histophorus Valenciennes, 1837 – (Walking goby). Retrieved from https://www.fishbase.se/summary/Scartelaos-histophorus.html
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Boddart's Blue-spotted Mudskipper (Boleophthalmus boddarti)

Boddart's Blue-spotted Mudskipper (Boleophthalmus boddarti)

A small Boddart's Blue-spotted Mudskipper found in Sungei Buloh Wetland Reserve.

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Boleophthalmus boddarti
Common Name(s): Boddart's Blue-spotted Mudskipper, Boddart's Goggle-eyed Goby, Blue-spotted Mudskipper

Presence in Singapore: Native
Habitat: Coastal: Open mudflats near and beyond the mangrove roots.
Conservation status: Vulnerable (Red Data Book 3)

This genus of large mudskippers are unmistakable for they are commonly filmed for documentaries due to their range of behaviours. The Boddart's Blue-spotted Mudskipper can reach a maximum recorded length of 22cm and can be separated from other blue-spotted mudskippers via its slanting black stripes. As its name suggests, both the sides of the body and fins are covered in blue spots. Their dorsal fins are impressive with long, filamentous spines.

The Boddart's Blue-spotted Mudskipper lives out on the open mudflats that are revealed during low tide beyond the mangrove trees. Larger individuals are found further out than smaller individuals, which reside closer to the trees. During high tide, this species hide in their burrows where there is an air pocket inside. 

This mudskipper has a stocky build which it smoothly drags across the mudflats it calls home. Its large mouth appears to be more for burrowing and fighting rather than capturing prey, for it leads a herbivorous and detritivorous lifestyle. To feed, they skim the mud by moving their heads side to side, scraping up the microbes present on the surface such as algae.

Males put on a beautiful display by jumping into the air with fins fully flared, in hopes of attracting a female. If a female is interested, they enter the burrow together to mate. Very small juveniles are pinkish (see Ong & Tay, 2024). 

Mudskippers roll on their sides to keep themselves moist!

A juvenile Boddart's Blue-spotted Mudskipper.

References

• FishBase. Boleophthalmus boddarti (Pallas, 1770) – (Boddart's goggle-eyed goby). Retrieved from https://fishbase.se/summary/4901
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.
• Ong JXL & Tay JX (2024) Biodiversity Record: Fish fauna of a mangrove tide pool at Sungei Buloh. Nature in Singapore, 17: e2024056. DOI: 10.26107/NIS-2024-0056

Dusky-gilled Mudskipper (Periophthalmus variabilis)

Dusky-gilled Mudskipper (Periophthalmus variabilis)

A small Dusky-gilled Mudskipper on the sandy shores of St John's Island.

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Periophthalmus variabilis
Common Name(s): Dusky-gilled Mudskipper

Presence in Singapore: Native
Habitat: Coastal: Mangrove forests down to lower intertidal zones.
Conservation status: Vulnerable (Red Data Book 3)

The Dusky-gilled Mudskipper is a small species, reaching a maximum total length of 7cm. This species is identified by its variable black blotches that usually fade towards the bottom. It also has tiny whitish-blue spots across the body. Its red dorsal fins are similar to the Silver-lined Mudskipper but in the first dorsal fin, the black margin curves down to the base and it lacks the many white specks. 

The Dusky-gilled Mudskipper was formerly synonymized with Periophthalmus novemradiatus, leading to some outdated signboards in our parks. It is now a recognized separate species from its relative further north. 

This species shares a similar habitat range to most of its relatives, being abundant in back mangroves all the way down to intertidal zones. It doesn't seem to stray far from the shelter of mangroves however unlike the Gold-spotted Mudskipper. It is an opportunistic carnivore that feeds on small invertebrates.

Territorial display of a Dusky-gilled Mudskipper with dorsal fins in full view.

References

• FishBase. Periophthalmus variabilis Eggert, 1935 – (mudskipper). Retrieved from https://fishbase.se/summary/65362
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Slender Mudskipper (Periophthalmus gracilis)

 Slender Mudskipper (Periophthalmus gracilis)

A Slender Mudskipper seen on the sandy shores of St John's Island.

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Periophthalmus gracilis
Common Name(s): Slender Mudskipper, Graceful Mudskipper

Presence in Singapore: Native
Habitat: Coastal: Mangrove forests down to lower intertidal zones.
Conservation status: Vulnerable (Red Data Book 3)

The Slender Mudskipper is a small species, reaching a maximum recorded length of 4.5cm. This species usually has thin, silver stripes and slanting black bands on the side of its body, making it easy to confuse with the Silver-lined Mudskipper and Dusky-gilled Mudskipper. The best way to identify this mudskipper is to look at the gap between its two dorsal fins, which are very far part compared to its relatives. The first dorsal fin is also small and rectangular, with dark patterns and blue margins over a lighter colour base compared to the red base of the two earlier mentioned species.

This is a common species, being seen in the back mangroves down to open intertidal zones such as mudflats. It is often seen alongside its relatives listed in this blog as well. Being an opportunistic carnivore, it preys on small invertebrates. 

A Slender Mudskipper caught via hand-line for dorsal fin inspection. (Photograph by: Jiayuan Lin)

References

• FishBase. Periophthalmus gracilis Eggert, 1935 – Graceful (Slender) Mudskipper. Retrieved from https://www.fishbase.se/summary/Periophthalmus-gracilis
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Gold-spotted Mudskipper (Periophthalmus chrysospilos)

Gold-spotted Mudskipper (Periophthalmus chrysospilos)

A male Gold-spotted Mudskipper identified by the elongated first spine of the first dorsal fin. This was seen in the intertidal zone of Bukit Chermin Boardwalk.

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Periophthalmus chrysospilos
Common Name(s): Gold-spotted Mudskipper

Presence in Singapore: Native
Habitat: Coastal: Intertidal zones such as sandy beaches and mudflats
Conservation status: Vulnerable (Red Data Book 3)

The Gold-spotted Mudskipper is an average-sized species, reaching around 10cm long usually. This species is easily identified by the orange-gold spots that cover the sides of its body, resulting in its common name. It also has bright orange dorsal fins that stand out from the other mudskippers in Singapore. In the males, the first dorsal spine is very elongated, which is a feature not seen in its relatives under the same genus locally.

The Gold-spotted Mudskipper is abundant in open intertidal zones along the coast such as mudflats and sandy beaches. It is rarely seen inside mangrove forests where its relatives are common. During high tide, they go further up the beach or wait it out on mangrove roots and other elevated surfaces.

A Gold-spotted Mudskipper braving the high tide and strong winds while clinging to a mangrove sapling.

This species is omnivorous and appears to have different feeding styles. It hunts smaller invertebrates on-sight but also grazes on surfaces for algae and microorganisms. We have observed this species grazing on the rocks they're sitting on every time the wave crashes into it.

Territorial display of the Gold-spotted Mudskipper.

References

• FishBase. Periophthalmus chrysospilos Bleeker, 1853 – Gold-spotted Mudskipper. Retrieved from https://www.fishbase.se/summary/Periophthalmus-chrysospilos.html
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Silver-lined Mudskipper (Periophthalmus argentilineatus)

Silver-lined Mudskipper (Periophthalmus argentilineatus)

A Silverlined Mudskipper seen on St John's Island, where it is rather plentiful. 

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Periophthalmus argentilineatus
Common Name(s): Silver-lined Mudskipper, Barred Mudskipper

Presence in Singapore: Native
Habitat: Coastal: Mangrove forests down to lower intertidal zones.
Conservation status: Vulnerable (Red Data Book 3)

This is an abundant species seen in Singapore from both inside mangrove forests to even sandy shores that at least meet a patch of mangroves (indicating some mud). The Silver-lined Mudskipper is an average-sized mudskipper, reaching just under 10cm at max. It is named after the silver stripes on the sides of its body but other species can have similar patterns as well. Thus, a shot of the raised dorsal fins can help separate it from similar-looking species in the region. The first dorsal fin is red with a black and white margin running from the top to the back of the fin, while the red area has many spots. 

A Silver-lined Mudskipper flaring its dorsal fins to another of its kind. (Photograph by: Lumin Ong)

This species is an opportunistic carnivore, feeding on whatever could feed in its mouth such as small invertebrates.

A Silver-lined Mudskipper feeding on what appears to be a polychaete worm that it dug out from the mud.

Although not recorded in Singapore (so far), Periophthalmus kalolo frequently appears alongside this species elsewhere and look pretty much the same. A ventral view of the pelvic fin is currently the best way to differentiate them (Polgar, 2014). 

References

• Polgar, G. Gobiidae: Oxudercinae – Periophthalmus argentilineatus Valenciennes, 1837. Retrieved from http://www.mudskipper.it/SpeciesPages/arge.html
• FishBase. Periophthalmus argentilineatus (Valenciennes, 1837) – Barred Mudskipper. Retrieved from https://www.fishbase.se/summary/Periophthalmus-argentilineatus
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Yellow-spotted Mudskipper (Periophthalmus walailakae)

Yellow-spotted Mudskipper (Periophthalmus walailakae)

A Yellowspotted Mudskipper seen in Berlayer Creek. (Photograph by: Lumin Ong)

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Periophthalmus walailakae
Common Name(s): Yellow-spotted Mudskipper, Walailak's Mudskipper

Presence in Singapore: Native
Habitat: Coastal: Mangrove forests
Conservation status: Vulnerable (Red Data Book 3)

This is a large mudskipper species for its genus, reaching nearly 13cm in length at max. It is relatively common in our muddy mangrove forests but can also be seen further out along the shore, sometimes in sandier habitats. The top half of its body has several saddle-like stripes while its flanks are covered with yellow spots, giving it the common name it's known by locally. Its first dorsal fin is un-patterned, being red with black and white margins along the top down to the back. 

The Yellow-spotted Mudskipper is an opportunistic carnivore, preying on small crustaceans and other invertebrates. Its burrows are usually further back in the mangroves in mud and it doesn't seem to stray far from the shelter of the mangrove forests.

A Yellow-spotted Mudskipper showing a bit of its first dorsal fin. (Photograph by: Lumin Ong)

References

• FishBase. Periophthalmus walailakae. Country species summary for Singapore. Retrieved from https://www.fishbase.se/Country/CountrySpeciesSummary.php?c_code=764&id=61443
• Polgar, G. Gobiidae: Oxudercinae – Periophthalmus walailakae Darumas & Tantichodok, 2002. Retrieved from http://www.mudskipper.it/SpeciesPages/wala.html
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Giant Mudskipper (Periophthalmodon schlosseri)

Giant Mudskipper (Periophthalmodon schlosseri)

A Giant Mudskipper emerging from its burrow in Pasir Ris Park's mangroves. (Photograph by: Lumin Ong)

Family: Oxudercidae (Subfamily Oxudercinae - Mudskippers)

Species Name: Periophthalmodon schlosseri
Common Name(s): Giant Mudskipper

Presence in Singapore: Native
Habitat: Coastal: muddy mangrove swamps and mudflats.
Conservation status: Least Concern (Red Data Book 3)

This is the largest mudskipper seen in Singapore and one of the largest in the entire world for it can reach almost 30cm in length. Due to its sheer size and abundance in the right habitats, it is also the most often seen mudskipper in Singapore as it is hard to miss. It is easily recognizable via a dark, horizontal stripe that runs along the sides of its body starting from the eyes. It is also peppered with light blue spots towards the bottom half of its body.

The Giant Mudskipper is carnivorous, possessing impressive fangs for its kind. It preys on smaller fishes, crustaceans and have even been known to eat reptiles such as snakes. They have been observed digging for burrowing prey such as eels. This highly territorial species chases other individuals that get too close.

The Giant Mudskipper inhabits mangrove swamps where the substrate is muddy and can even be found further out on open mudflats. They dig large burrows marked by a round pool visible at low tide, where the mudskipper usually sits in. In mated pairs, both the male and female help to maintain the burrow These pools are usually shelter to smaller mangrove fishes such as their goby cousins during low tide (see Ong & Tay, 2024), which are often too small for the mudskipper to bother about. They can be seen waiting out the high tide on mangrove roots and other elevated surfaces. 

A Giant Mudskipper hard at work digging in Sungei Buloh Wetland Reserve. (Photograph by: Lumin Ong)

A young Giant Mudskipper taking shelter on a rock during high tide. (Photograph by: Lumin Ong)

References

• FishBase. Periophthalmodon schlosseri (Pallas, 1770) – Giant Mudskipper. Retrieved from https://www.fishbase.se/summary/Periophthalmodon-schlosseri
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.
• Ong JXL & Tay JX (2024) Biodiversity Record: Fish fauna of a mangrove tide pool at Sungei Buloh. Nature in Singapore, 17: e2024056. DOI: 10.26107/NIS-2024-0056

Mangrove Jack (Lutjanus argentimaculatus)

  Mangrove Jack (Lutjanus argentimaculatus)

A large individual found in Pasir Ris Park's mangroves which has seen some fighting with anglers. (Photograph by: Lumin Ong)

Family: Lutjanidae
Species Name: Lutjanus argentimaculatus
Common Name(s): Mangrove Jack, Mangrove Red Snapper

Presence in Singapore: Native
Habitat: Based on age - Adults: offshore coral reefs, Juveniles: Estuaries and rivers.
Conservation status: Near Threatened (Red Data Book 3)

The Mangrove Jack is a name known to many people as a game fish, food and even pets. This euryhaline fish covers a wide range of habitats depending on its age. Younger adults and juveniles inhabit inland waters such as estuaries and even freshwater streams, while adults move to deeper waters offshore over coral reefs. 

Growing up to a maximum size of 1.5 meters, this is a formidable predator in the ecosystems it occurs on whatever fits into its mouth. Like its relatives, it possesses sizable fangs that helps in snagging unsuspecting prey. It is an ambush predator, carefully inspecting and sneaking around shelters such as mangrove roots for its prey before catching them with a burst of speed.

As mentioned earlier, the Mangrove Jack is a popular commercial fish that is caught and farmed for its meat. It is also famous among fishermen for its burst of speed upon getting hooked.

A small Mangrove Jack found in full saltwater around Sentosa. (Photograph by: Lumin Ong)

References

• FishBase. Lutjanus argentimaculatus (Forsskål, 1775) – Mangrove Red Snapper. Retrieved from https://www.fishbase.se/summary/lutjanus-argentimaculatus.html.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Mangrove Cardinalfish (Yarica hyalosoma)

Mangrove Cardinalfish (Yarica hyalosoma)

A school of Mangrove Cardinalfish resting in the mouth of Sungei Cina. (Photograph by: Lumin Ong)

Family: Apogonidae

Species Name: Yarica hyalosoma
Common Name(s): Mangrove Cardinalfish, Humpbacked Cardinalfish

Presence in Singapore: Native
Habitat: Brackish such as estuaries and mangrove swamps. Enters the lower reaches of freshwater rivers as well.
Conservation status: Least Concern (Red Data Book 3)

The Mangrove Cardinalfish is a unique-looking fish that can be seen in freshwater to more commonly, brackish habitats. As its common name suggests, it can be found in our mangrove swamps, creeks and more during rising to high tide. It can be also seen in tidal rivers, river mouths and along the coast if it can't enter the mangrove forest due to low water levels.

The genus Yarica is said to include two species but so far, Y.hyalosoma seems to be the only widely recognized and documented species. It stands out from other cardinalfishes due to its habitat preferences and stocky build, which can reach 17cm in length. The Mangrove Cardinalfish is generally grey with a spot on both sides of the peduncle (base of tail). 

Being a cardinalfish, the Mangrove Cardinalfish is a predator with great eyesight due to its big eyes, picking off smaller fish and invertebrates in the water column with the help of its even bigger mouth. It is also a mouthbrooder just like its relatives.

A Mangrove Cardinalfish spotted in Sungei Buloh Wetland Reserve. (Photograph by: Lumin Ong)

References

• FishBase. Yarica hyalosoma (Bleeker, 1852) – Humpbacked Cardinalfish. Retrieved from https://www.fishbase.se/summary/Yarica-hyalosoma.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Silver Moony (Monodactylus argenteus)

Silver Moony (Monodactylus argenteus)

A juvenile Silver Moony found in a pontoon. (Photography by: Lumin Ong)

Family: Monodactylidae
Species Name: Monodactylus argenteus
Common Name(s): Silver Moony, Diamondfish, Mono

Presence in Singapore: Native
Habitat: Coastal such as mangrove estuaries, tidal rivers and shallow reefs. Occasionally seen in lower freshwater stretches.
Conservation status: Near Threatened (Red Data Book 3)

The Silver Moony is a popular fish in the aquarium trade, especially for brackish aquariums but however, it is often advertised as a purely freshwater fish which isn't true. Being a euryhaline fish, the Silver Moony is relatively common in our coastal habitats ranging from brackish mangrove swamps to saltwater ones such as along seawalls, and in shallow reefs. 

Adult Silver Moonies can reach a maximum known length of 27cm but are usually half that size. Juveniles are more common in the upper reaches of their habitats while adults stay more at the coast. This is a unique-looking fish, being shaped like a diamond as its common name suggests with yellow fins standing out along its silver body. Very young juveniles are dark with orange fins.

They are known to form large schools but juveniles are usually solitary or found with a few other individuals. This fish is omnivorous, feeding on plankton, detritus and other small mid-water edibles. Interestingly, the juveniles are known to approach similar-sized and larger fishes in an attempt to "clean" them but are often met with annoyance.

A trio of very young Silver moonies.

A juvenile Silver Moony attempting to "clean" a Mangrove Cardinalfish.

References

• FishBase. Monodactylus argenteus (Linnaeus, 1758) – Silver Moony. Retrieved from https://www.fishbase.se/summary/Monodactylus-argenteus.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

 

Green Spotted Pufferfish (Dichotomyctere nigrovidis)

 Green Spotted Pufferfish (Dichotomyctere nigroviridis)

A Green Spotted Pufferfish at Admiralty Park during high tide. (Photograph by: Lumin Ong)

Family: Tetraodontidae
Species Name: Dichotomyctere nigroviridis
Common Name(s): Green Spotted Pufferfish

Presence in Singapore: Native
Habitat: Estuarine such as in mangrove swamps. Enters freshwater rivers and streams etc.
Conservation status: Least Concern (Red Data Book 3)

The Green Spotted Pufferfish is probably the most commonly seen pufferfish in Singapore as it is abundant in our mangrove habitats, which it enters during a rising tide. It is also a popular aquarium fish, where they're sold as freshwater fishes when they thrive much better in more saline waters. This pufferfish can grow up to 17cm but are usually seen at half that size. It is unique looking among its kind in Singapore, making it easy to identify thanks to its colouration and patternings.

Like all pufferfishes, the Green Spotted Pufferfish is mostly a hunter of hard-shelled invertebrates, which it uses its beak-like teeth to crush. It is not picky however and will even go for other fishes. When threatened by potential predators, they will puff up by inhaling water, revealing small spines all over the body in the process. Green Spotted Pufferfishes also contain the deadly tetrodotoxin which can kill if the fish is consumed.

A juvenile Green Spotted Pufferfish at the surface in Sungei Buloh Wetland Reserve.

References

• FishBase. Dichotomyctere nigroviridis (Marion de Procé, 1822) – Spotted Green Pufferfish. Retrieved from https://fishbase.se/summary/7763.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Barramundi (Lates calcarifer)

Barramundi (Lates calcarifer)

A medium-sized Barramundi found patrolling in the shallow waters at Eagle Point.

Family: Latidae
Species Name: Lates calcarifer
Common Name(s): Barramundi, Asian Sea Bass, Giant Sea Perch

Presence in Singapore: Native
Habitat: Varied. Ranges from freshwater rivers to coastal habitats such as lagoons.
Conservation status: Data Deficient (Red Data Book 3), Least Concern (IUCN)

A fish most people should know, be it by name and/or taste. In Singapore, the Barramundi can be found in a variety of habitats with varying salinity such as lagoons, estuaries, freshwater and tidal rivers. The Barramundi is a large, predatory fish that have reached lengths of up to two meters on record. It hunts near the bottom for smaller fishes, crustaceans and molluscs as adults while the juveniles feed on zooplankton. It is a highly recognizable fish with its elongated body and sloping head, usually clad in grey of varying darkness. 

Adult Barramundi that usually reside in the upper reaches of freshwater habitats such as rivers migrate down to estuaries to breed. The juveniles then mature in coastal habitats such as mangrove swamps before repeating the cycle. Populations of Barramundi are known to establish in saltwater as well.

The Barramundi is an important food fish world wide and are raised in aquaculture across many countries including Singapore. It is also a popular sport fish due to the fight it's able to give anglers.

References

• FishBase. Lates calcarifer (Bloch, 1790) – Barramundi. Retrieved from https://www.fishbase.se/summary/Lates-calcarifer.html.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Indian Mud Moray (Gymnothorax tile)

 Indian Mud Moray (Gymnothorax tile)

An Indian Mud Moray found at the side of a tidal river during an upset in water chemistry.

Family: Muraenidae
Species Name: Gymnothorax tile
Common Name(s): Indian Mud Moray

Presence in Singapore: Native
Habitat: Muddy estuaries, mangrove swamps, river mouths.
Conservation status: Least Concern (Red Data Book 3)

This moray eel is abundant in our estuaries but in true moray eel fashion, it is tough to find due to its elusive nature and that their habitats are usually muddy. Due to its euryhaline nature, it is often sold as a freshwater in the aquarium trade but it thrives much better and longer in brackish water. Growing to a length of 60cm, the Indian Mud Moray preys on other fishes and crustaceans which it uses its strong sense of smell to locate, making up for their poor eyesight. It also has a recognizable look among local moray eels, exhibiting a dirty brown base colour with tiny, yellow speckles.

Like all moray eels, the Indian Mud Moray possesses two sets of jaws: 1. the oral jaw which is used to do the initial grasping of prey and 2. a pharyngeal jaw resting inside that helps to pull the prey in or tear off chunks. 

Another Indian Mud Moray found at the side of a tidal river during an upset in water chemistry.  It is sharing the space with its prey - a Penaeid prawn, showing the direness of the situation.

References

• FishBase. Gymnothorax tile (Hamilton, 1822) – Freshwater Moray. Retrieved from https://www.fishbase.se/summary/Gymnothorax-tile.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Mangrove Pipefish (Ichthyocampus carce)

Mangrove Pipefish (Ichthyocampus carce)

A large-sized Mangrove Pipefish compared to an usual-sized individual!

Family: Syngnathidae

Species Name: Ichthyocampus carce
Common Name(s): Mangrove Pipefish, Freshwater Pipefish, Indian Freshwater Pipefish

Presence in Singapore: Native
Habitat: Mangroves and estuaries, slow-moving to still water such as pools. Freshwater streams and rivers.
Conservation status: Vulnerable (Red Data Book 3)

One of the few estuarine Syngnathid (seahorses and pipefishes) that we can find in Singapore and the most readily seen too. It can be found in relative abundance during low tide, where it inhabits isolated pools and slow-moving creeks. Despite their numbers, their thin bodies and brown colouration makes them tough to spot. They can grow up to 15cm in length but are usually found at sizes half of that, adding on to the difficulty. 

For a fish with such a seemingly small mouth, they are voracious predators of small invertebrates and zooplankton, which they snake along the sediment or around mangrove roots to stalk.

Like all Syngnathids, the males raises the eggs. The male Mangrove Pipefish carries the eggs in a brood pouch found under the tail.

One out of several Mangrove Pipefish found in an isolated pool with many estuarine gobies.

References

• ​FishBase. Ichthyocampus carce (Hamilton, 1822) – Freshwater Pipefish. Retrieved from https://www.fishbase.se/summary/Ichthyocampus-carce.html.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• Ong JXL & Tay JX (2024) Biodiversity Record: Fish fauna of a mangrove tide pool at Sungei Buloh. Nature in Singapore, 17: e2024056. DOI: 10.26107/NIS-2024-0056
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Milkfish (Chanos chanos)

Milkfish (Chanos chanos)

A school of Milkfish at Sungei Buloh Wetland Reserve's main bridge.

Family: Chanidae
Species Name: Chanos chanos
Common Name(s): Milkfish

Presence in Singapore: Native
Habitat: Coastal and offshore waters, often enters esutaries.
Conservation status: Least Concern (Red Data Book 3)

Although adults live offshore, Milkfish are known to frequently enter shallow coastal waters and estuaries, sometimes touching freshwater. They can be commonly seen in schools during the rising and high tide in habitats such as tidal rivers, where they sometimes mix with mullets. These are sizable fishes, growing to a maximum length of 1.8 meters but usually average out at a meter and are recognizable by their deeply forked tail.

Having a small mouth, Milkfish are omnivorous and feed on a variety of pelagic organisms such as zooplankton and fish larvae. They also feed near the bottom on benthic invertebrates, algae and even detritus. Milkfish themselves are important food fish for humans and are farmed as well. 

The Milkfish is the sole-living representative of the family Chanidae, which includes several extinct genera that existed during the Cretaceous. 

Adult Milkfish spawn in the sea, where the maturing juveniles swim back to coastal waters or even further upstream to grow. 

A small Milkfish following a school of mullets.

References

• FishBase. Chanos chanos (Fabricius, 1775) – Milkfish. Retrieved from https://www.fishbase.se/summary/chanos-chanos.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.

Javanese Ricefish (Oryzias javanicus)

Javanese Ricefish (Oryzias javanicus)

A school of Javanese Ricefish at Pasir Ris Park's Mangrove Boardwalk (Photograph by: Lumin Ong)

Family: Adrianichthyidae
Species Name: Oryzias javanicus
Common Name(s): Javanese Ricefish

Presence in Singapore: Native
Habitat: Various brackish and freshwater habitats like mangrove swamps and canals.
Conservation status: Least Concern (Red Data Book 3)

A small but very adaptable fish commonly seen in not only our estuaries, but sometimes also in freshwater as well. The Javanese Ricefish can be found in schools of varying sizes and are recognizable by their guppy-like appearance. They have a distinct yellow ring around their tail which helps to separate them from other ricefish species found in the region.

Growing to a maximum size of 4.5cm, the Javanese Ricefish is mainly a micropredator of tiny crustaceans and protozoa but are known to consume detritus and algae too. 

The female carries her eggs outside her genital pore via filaments.

A Javanese Ricefish at Eagle Point during a rising tide.

References

• FishBase. Oryzias javanicus (Bleeker, 1854) – Javanese Ricefish. Retrieved from https://www.fishbase.se/summary/Oryzias-javanicus.html.
• Lim, K.K.P. & Low, J.K.Y. 1998. A Guide to Common Marine Fishes of Singapore. Singapore Science Centre, 163 pp. ISBN 981-00-9904-5.
• National Parks Board (NParks). Marine Fishes. Retrieved from https://www.nparks.gov.sg/nature/species-list/marine-fishes.