This species is often confused with the nominal congeners C. marulius (Hamilton, 1822) and C. melanoptera (Bleeker, 1855) with all three presenting taxonomic problems.

For example, C. marulioides exhibits a number of variations in colour pattern depending on collection locality with the most common possessing a brownish base colour with a series of dark, chevron-like markings along each flank and some scales margined posteriorly in white.

Prefers a dimly-lit aquarium with plenty of cover in the form of live plants, driftwood branches, terracotta pipes, plant pots, etc., arranged to form a network of nooks, crannies, and shaded spots.

Surface vegetation such as Ceratopteris spp. is also appreciated and makes the fish less inclined to conceal themselves.

G. filamentosa has appeared in the ornamental trade but is evidently delicate and therefore recommended only to experienced aquarists.

It can be told apart from congeners by the following combination of characters: possession of filamentous dorsal and anal-fin rays in males; body transparent to translucent yellowish-brown colour in life; absence of a highly-extended second anal-fin spine; absence of carmine-red pigmentation in the dorsal, anal an…

This species is a near-exclusive inhabitant of the upper water column and appreciates surface cover in the form of floating or overhanging vegetation.

Other décor is relatively unimportant but can consist of a sandy substrate with leaf litter plus some large driftwood branches and twisted roots.

Plants which can grow rooted in sand can al…

Type locality is ‘Palembang, Sumatra, Indonesia’, but this species is widely-distributed throughout much of Southeast Asia including major river systems in Thailand, Laos, Cambodia, Vietnam and Peninsular Malaysia plus the Greater Sunda Islands of Sumatra, Borneo and Java.

It’s been extensively recorded from the Mekong, Cha…

Generally peaceful though it may predate on smaller fishes and is somewhat timid so does not compete well with much larger, robust or otherwise boisterous species.

Peaceful, comparably-sized cyprinids, loaches and other catfishes perhaps constitute the best options but be sure to research your choices thoroughly prior to purchase.

This species has occasionally appears in the aquarium trade in substantial quantities but is not an easy species to maintain in captivity and often susceptible to disease post-import.

It’s sometimes sold as ‘ornate licorice gourami’.

It’s among the smallest members of the gen…

It’s care requirements, disposition, and especially conservation status dictate that it should be maintained alone or alongside a group of small, peaceful cyprinids such as Boraras or Sundadanio spp.

Likewise, different Parosphromenus spp. should not be kept together since the females of many are very difficult to tell apart and some are undoubtedly capable of hybridising.

Not recommended for the standard community set-up for reasons already touched upon. It’s requirements and disposition mean it’s best kept alone or with very peaceful species since much bigger or more vigorous fishes are likely to intimidate and outcompete it.

Some small cyprinids and loaches that inhabit similar environments in nature are compat…

This species is not often seen in the aquarium hobby but occasionally exported as bycatch among shipments of other fishes. It was described as a subspecies of the closely-related ‘P.‘ binotatus but is currently considered distinct on a tentative basis as per Ng and Tan (1999) who stated it is ‘likely’ that the two represent extreme colour forms of a single, variably-patterned species.