Taxonomy & naming
Trichopodus poptae was described by Benny K.K. Low, Heok Hui Tan, and Ralf Britz in 2014, in Ichthyologische Erkundung der Süßgewässer (Ichthyological Exploration of Freshwaters), volume 25, number 1, pages 69–77, under the title 'Trichopodus poptae, a new anabantoid fish from Borneo.' The type locality is Kalimantan, the Indonesian portion of Borneo. Eschmeyer's Catalog of Fishes treats the valid name as Trichopodus poptae Low, Tan & Britz, 2014.
The species belongs to the family Osphronemidae, the gouramis and pikehead, and is placed within the subfamily Luciocephalinae. The genus Trichopodus was long sunk into Trichogaster, but molecular and morphological work has restored the two as separate genera; Trichopodus is characterised in part by the long, thread-like ventral fins that are a hallmark of many gouramis in the group. T. poptae was the most recently described species in the genus at the time of writing and is distinguished from its congeners — T. trichopterus, T. leerii, T. microlepis, and T. pectoralis — by its comparatively simple coloration: a plain brown body carrying a blackish reticulate or net-like pattern, lacking the bold spots or iridescent sheen of its relatives.
The specific epithet honours Clara Antoinette Popta (1860–1929), a Dutch ichthyologist at the Leiden natural history museum who worked on the fishes of Borneo and was among the first women to practice ichthyology as a professional discipline. The iNaturalist common name 'False-eye Gourami' has circulated informally but is not yet standardised in the major databases.
Morphology
T. poptae is a moderately elongate, laterally compressed gourami, reaching a recorded maximum of 2.5 in standard length according to FishBase — making it one of the smaller species in the genus. Like other Trichopodus it possesses the family's characteristic labyrinth organ, a suprabranchial accessory respiratory structure housed above the gills, and the long, filamentous first rays of the ventral fins that serve as touch organs and are a signature of gourami biology.
The adult colour pattern is described in the original description as plain brown with a blackish reticulate (net-like) pattern overlying the flanks. Juveniles may show a faint dark spot in the dorsal-posterior area of the body, which fades with maturity. This understated appearance, lacking the strong spots, bars, or metallic sheen present in congeners such as T. leerii or T. trichopterus, is one of the primary characters used to separate T. poptae from other members of the genus. Sexual dimorphism in the species has not been characterised in detail in the available literature.
Habitat
Trichopodus poptae is endemic to Kalimantan on the island of Borneo, with records from West Kalimantan noted in the IUCN assessment. It inhabits peat-swamp forest waterways — the dark, tannin-stained blackwater streams and pools that develop over deep accumulations of partially decayed organic matter in lowland Bornean forest. These are extreme environments by the standards of freshwater fish: the water is deeply acidic (pH values below 4 are not unusual in primary peat swamp), soft, warm, and nearly opaque with humic acids and dissolved organic carbon.
As a labyrinth fish, T. poptae is well adapted to the low dissolved-oxygen conditions that characterise stagnant or near-stagnant peat-swamp water — the suprabranchial organ allows the fish to breathe atmospheric air at the surface, an essential adaptation in habitats where dissolved oxygen can drop to near-zero. The peat-swamp biome is also one of the most habitat-specialised freshwater ecosystems in Southeast Asia, supporting numerous endemic species found nowhere else. T. poptae shares this environment with other gourami relatives and a rich community of equally range-restricted fishes.
Feeding
No dedicated dietary studies are available for Trichopodus poptae. Based on the feeding ecology of other Trichopodus species and the general biology of small gouramis in peat-swamp habitats, the species is inferred to be an opportunistic omnivore. In the wild it likely consumes small invertebrates — insect larvae, microcrustaceans, and surface-fallen insects — as well as organic detritus, zooplankton, and plant material available in the peat-swamp water column and leaf litter.
In the aquarium, congeners such as T. trichopterus and T. leerii accept a broad range of prepared and live foods including flake, micro-pellets, frozen Daphnia, brine shrimp, and bloodworm. The same diet would be appropriate for T. poptae, though its smaller adult size — no more than about 2.5 in SL — means that food particle size should be kept appropriately fine.
Mating
Trichopodus poptae has not been bred in the aquarium with any documented regularity, and detailed observations of its courtship behaviour are absent from the published literature. Based on the reproductive biology of the genus, T. poptae is expected to be a bubble-nest builder: the male constructs a raft of mucus-bound bubbles at the water surface, often anchored among floating vegetation or surface debris, and courts females through lateral displays and fin spreading.
In congeners, males become territorial around the nest site during the breeding period and court females with intensified colour displays. The male drives the female toward the nest, where spawning occurs through a body-wrapping embrace typical of labyrinth fishes. Given the peat-swamp origin of T. poptae, it is probable that breeding behaviour is triggered by the very soft, acidic, and warm water conditions of its native habitat, and that replicating those conditions closely would be important in any captive breeding attempt.
Breeding
No captive breeding records for Trichopodus poptae are documented in the available literature. The account here is necessarily inferential, drawn from the biology of the genus and close relatives in peat-swamp habitats.
As an expected bubble-nest builder in the Trichopodus mould, the male would construct a surface nest and guard both the eggs and hatched fry there after spawning, which takes place beneath or at the nest. Eggs are buoyant and are gathered by the male and placed into the nest. Parental care — at least by the male — is typical for the group; the female is usually removed after spawning to prevent the male from harassing her. Water chemistry replicating the species' native peat-swamp conditions (pH in the range of 4–6, very soft water, temperature in the high 20s Celsius) would likely be needed to condition adults and stimulate spawning. Data on clutch size, incubation period, and fry development for this species are not available.
In the aquarium
Trichopodus poptae is not established in the aquarium hobby and is rarely if ever available in the trade. No hobbyist care sheets or forum accounts specific to the species were found in the literature reviewed. General principles for peat-swamp gouramis apply: the species would require soft, acidic, heavily tannin-stained water replicating its native blackwater conditions, warm temperatures (approximately 75–82 °F), very gentle or minimal filtration to avoid current, and a well-covered tank to prevent the fish from accessing cold air at the surface, which can damage the labyrinth organ.
As a small gourami reaching only about 2.5 in SL, T. poptae would be suitable for a species-only or carefully chosen community setup with other small, soft-water fishes. The addition of dried leaf litter, peat filtration, and driftwood to create authentic blackwater conditions would be appropriate. Surface access is essential, as for all labyrinth fishes. Until captive populations are established and care requirements better documented, the species should be regarded as a specialist subject for experienced aquarists with a focus on peat-swamp biotopes rather than a general community fish.
Conservation
Trichopodus poptae is assessed as Data Deficient (DD) on the IUCN Red List under version 3.1. The Data Deficient listing reflects the very limited information available on the species' population size, range extent, and ecological requirements at the time of assessment, not an absence of concern: DD status explicitly does not mean a species is not at risk, but that current data are insufficient to apply a threat category.
The habitat of T. poptae — peat-swamp forest in West Kalimantan — is under severe pressure from land conversion for oil-palm plantations, logging, drainage for agriculture, and the repeated burning of peat that accompanies land clearing. Kalimantan has lost a very large proportion of its peat-swamp forest over the past several decades, and this destruction continues. Species endemic to this biome, particularly those known from only a few localities, are inherently vulnerable. The IUCN assessment notes habitat loss in the peat swamps of West Kalimantan as a threat. Given the narrow endemism of T. poptae and the trajectory of its habitat, the species may warrant uplisting to a threat category when sufficient population data become available.