Edit Trigonostigma hengeli

You can suggest changes to this profile. A moderator will review each change.

Name

Scientific name

Trigonostigma hengeli

Described by

Authority Meinken, Year 1956, Bracketed

Family

Cyprinidae

Common names

Not recorded

Photograph credits

All 3 credited

Summary

Trigonostigma hengeli is a small rasbora from the Greater Sunda Islands, collected in Jambi province, Sumatra and apparently West Kalimanta…

Size and aquarium

Maximum size

30mm, standard length

Aquarium size

Minimum length 60 cm, Minimum depth 30 cm

Water

Water conditions

Temperature 23–28°C, pH 5–7.5

Hardness

1–10dGH

Conductivity

Not recorded

Behaviour

Temperament

Peaceful

Community suitability

Community-safe

Where it lives

Countries, regions, rivers and lakes

Indonesia, Borneo, Sumatra, Batang Hari

Writing

Etymology

Not written yet

Distribution

Certainly restricted to the Greater Sunda Islands although the exact extent of its range is unclear. Collections have occured in Jambi province, Sumatra and ap…

Habitat

Mostly inhabits gently flowing sections of forest streams and tributaries where submerged aquatic plants such as Cryptocoryne species grow thickly. The water i…

Aquarium size

Aquarium base dimensions of 60 ∗ 30 cm or equivalent should be the smallest considered since this species should be maintained in numbers.

Maintenance

Choice of decor is not especially critical although it tends to show better colouration when maintained in a well-furnished set-up with a dark substrate, and i…

Water conditions

Temperature: 23 – 28 °C pH: Even though the majority of fish entering the trade are wild caught this species is quite happy within the range 5.0 – 7.5. Hardnes…

Diet

Probably a micropredator feeding on small insects, worms, crustaceans, and other zooplankton in nature. In the aquarium it's easily-fed but the best condition …

Behaviour and compatibility

This species is very peaceful indeed making it an ideal resident of the well-maintained community tank. As it places no extreme demands in terms of water chemi…

Sexual dimorphism

Mature females are usually deeper-bodied and slightly larger than the slimmer, more intensely-coloured, males.

Reproduction

This species exhibits no parental care although it does utilise a different spawning method to most small cyprinids as the eggs are attached to the underside o…

Notes

T. hengeli is sometimes seen for sale with the trade name of 'glowlight rasbora' due to the distinctive orange patterning on the posterior part of the body but…

T. hengeli is sometimes seen for sale with the trade name of 'glowlight rasbora' due to the distinctive orange patterning on the posterior part of the body but we've refrained from using that name here because it's also commonly applied to Trigonopoma pauciperforatum.

It can be confused with the similar-looking T. heteromorpha and T. espei although on close inspection they're actually quite easy to tell apart. The basic body colouration of T. heteromorpha is pinkish, it has the deepest body shape of the three and the characteristic body marking is broader, more triangular in shape and darker in colour.

T. espei is generally a bright copper/reddish colour with a thinner, 'lambchop'-shaped body marking whereas T. hengeli is a slightly smaller fish with an overall greyish/colourless body colouration and a flash of bright orange pigmentation along the upper and anterior edges of the 'lambchop' marking.

T. somphongsi is the fourth, exceptionally rare, member of the genus but is very easy to distinguish from the others as the dark body marking is reduced to a thickish stripe.

The genus was erected by Kottelat and Witte (1999)[2] in order to separate members from the larger Rasbora grouping on the basis of the following combination of characters: colour pattern comprising a reddish, pinkish or orange body (in life) with a conspicuous black stripe extending from below dorsal-fin origin to middle of caudal-fin base and usually broadened anteriorly so as to have a triangular or hatchet shape (except in T. somphongsi in which the stripe is only slightly broader anteriorly); reproductive strategy in which eggs are deposited on the underside of broad leaves or similar structures.

Other characters distinguishing the genus (but not unique to it) are: miniature size (maximum 32 mm1.3 in SL in nature, though captive specimens may grow slightly larger); incomplete lateral line reduced to 6-9 pores; absence of barbels; 5 branched anal-fin rays; relatively deep body (not quantified).

Rasbora has long been recognised as a polyphyletic lineage as noted by Kottelat (1999) among others, and in 2010 the results of a phylogenetic analysis by Liao et al. suggested a number of changes in order to improve the taxonomy. The authors found species of rasborin genera to represent a monophyletic grouping existing in six clades and erected four new genera containing former members of Rasbora in order to preserve monophyly of the existing groups.

The first two of these clades contain new groupings Kottelatia and Brevibora, respectively. The third comprises Boraras, Horadandia, Rasboroides, and Trigonostigma, plus new genera Trigonopoma and Rasbosoma. However the results for Boraras and Trigonostigma were found to be inconclusive in some respects and further work regarding their phylogenetic position was recommended.

The fourth clade includes Rasbora semilineata, R. borapetensis, R. rubrodorsalis, and an undescribed fish similar to R. beauforti. Clade five consists of R. daniconius, R. hubbsi, R. paucisqualis, R. wilpita (plus allies), R. kobonensis, R. ornata, and R. cf. daniconius.

Clade six is subdivided into two groupings. The first contains R. einthovenii, R. elegans, and R. cephalotaenia, and the second R. lateristriata, R. argyrotaenia, R. volzii, R. paviana, R. rasbora (plus an undescribed related fish), R. caudimaculata, and R. trilineata.

As this final clade contains R. cephalotaenia, the type species of Rasbora, its members retain the generic name as do members of clade five because they don't differ sufficiently to warrant erection of a new genus or genera.

Shortly afterwards a paper investigating systematics of the subfamily Danioninae was published (Tang et al. 2010) The results differed significantly and the four new genera of Liao et al., plus Boraras and Trigonostigma, were synonymised with Rasbora based on an incomplete knowledge of relationships within the group, an approach described as 'more conservative'.

Though neither conclusion can be deemed 100% the system of Liao et al. is followed here on SF pending future studies, if only because we prefer to retain the familiar genera Boraras and Trigonostigma.

Editing needs JavaScript. This is the text as it was last saved.

Where does this come from?

My own experienceFor example, I've kept twelve in a planted 60 cm tank since March 2024.A website I sawFor example, an IUCN Red List assessment, a museum catalogue or a FishBase page.A paperFor example, Marshall et al. (2011), Water temperature differences in interfluvial palm swamp habitats of Paracheirodon axelrodi and P. simulans.A book, or something not onlineFor example, Tappin (2010), Rainbowfishes: their care and keeping in captivity.Something already on the pageFor example, the Behaviour and compatibility section already says this.

Web address

Paste the address of the page that says this. What counts as a source

DOI

Paste a DOI and we will look up the rest of the reference. A DOI looks like 10.11646/zootaxa.4694.4.1, and most papers print it on the first page.

Title

Enter the title of the paper, book or page. If you leave it empty, we will use the website's address.

Authors

Separate authors with semicolons, e.g. Tan, H.H.; Ng, P.K.L.

Year

Journal or publisher

Pages

Enter the page that says this, e.g. 218 or 218–221.

Anything worth adding

Describe what you saw, or which part of the source says this.

References

3 on this profile

Name

Scientific name

Described by

Family

Common names

Photograph credits

Summary

Size and aquarium

Maximum size

Aquarium size

Water

Water conditions

Hardness

Conductivity

Behaviour

Temperament

Social needs

Community suitability

Where it lives

Countries, regions, rivers and lakes

Writing

Etymology

Distribution

Habitat

Aquarium size

Maintenance

Water conditions

Diet

Behaviour and compatibility

Sexual dimorphism

Reproduction

Notes

References

References