Taxonomy & naming
Chilatherina pricei was described by Gerald R. Allen and Samuel J. Renyaan in 1996, in the journal Revue française d'Aquariologie (23(1–2): 5–8), under the title 'Chilatherina pricei, a new species of rainbowfish (Melanotaeniidae) from Irian Jaya'. The holotype, an 3.5 in SL male, was collected in the Reifafeif River about 2 mi upstream of Warironi Village on Yapen (Japen) Island, off the north coast of New Guinea, in what was then the Indonesian province of Irian Jaya (now Papua). Eschmeyer's Catalog of Fishes records the valid name as Chilatherina pricei Allen & Renyaan, 1996; because the species was described in Chilatherina, where it remains, no parenthetical authority is used.
Chilatherina is one of the rainbowfish genera (family Melanotaeniidae) endemic to New Guinea, a group within the silverside order Atheriniformes. Like the rest of the family, these are small, laterally compressed freshwater fishes of the New Guinea–Australia region. C. pricei sits among the more obscure members of the genus, with a restricted distribution and little published on it beyond the original description.
The specific epithet honours David Price, who — as the description records — lived periodically on Yapen Island with his family and collected New Guinea fishes and frogs, including the type specimens of this rainbowfish; he was among the collectors of the 1995 holotype. The genus name combines the Greek cheilos, 'lip', with atherina, the classical Greek name for the smelt or sand-smelt — a nod to the silverside affinities of the rainbowfishes.
Morphology
Chilatherina pricei is a small rainbowfish; the original description records a maximum length of about 3.5 in standard length. As in other members of the genus and family, the body is laterally compressed and moderately elongate, carrying the rainbowfishes' characteristic divided dorsal fin — a short anterior dorsal followed by a longer posterior dorsal — together with a long-based anal fin.
Beyond the original description, species-specific colour and meristic data for C. pricei are thin, and the fish is essentially absent from the aquarium hobby, so reliable live-colour accounts are scarce. Within the genus, Chilatherina are silvery to bluish or greenish fishes in which adult males run to deeper bodies, longer median fins, and stronger colour than females — the usual family pattern. Lacking published figures for this species, treat those points as genus-typical inference rather than confirmed for C. pricei.
Habitat
Chilatherina pricei is a narrow-range endemic of the Reifafeif River on Yapen (Japen) Island, off the north coast of New Guinea in Papua (formerly Irian Jaya), Indonesia. The type series was collected near Warironi Village, a few kilometres upstream of the river mouth. FishBase records it as a freshwater, demersal, tropical species occurring at shallow depths of roughly 0–7 ft, and notes that it is abundant in the main channel of the Reifafeif River.
The description characterises the habitat as a flowing channel over rock and boulder, where the fish gather in midwater. On the coastal plain the main channel runs about 49–98 ft wide and averages roughly 3–7 ft deep outside flood periods; further inland it narrows into rapids, waterfalls, and deep pools. In July 1995 the type river measured 76–80 °F at a pH of 7.5–8.1 — slightly alkaline tropical water. This is rheophilic, clear-water, rocky-bottom river rather than still lake.
What defines the distribution is how confined it is: one river system, essentially. That narrow endemism, on an island whose freshwater fauna is still incompletely surveyed, is why its conservation status is precarious.
Feeding
According to FishBase, Chilatherina pricei forms midwater aggregations to feed on algae and small invertebrates, mainly insects, and is assigned a low trophic level of about 2.6 — consistent with a largely herbivorous-to-omnivorous diet weighted toward plant and algal material supplemented by small prey.
That fits the general feeding ecology of rainbowfishes: opportunistic omnivores that graze algae and aufwuchs off submerged surfaces while picking aquatic and terrestrial invertebrates from the water column and surface. In a rocky, flowing channel, that means algae on the boulders plus drifting and emerging insects.
There is no aquarium feeding literature for C. pricei — it is effectively absent from the hobby. By analogy with related rainbowfishes you would offer a varied omnivore diet — quality flake and small pellets, frozen and live invertebrate foods, some vegetable or algal matter — but that is inference, not documented practice for this species.
Mating
No direct observations of courtship or spawning in Chilatherina pricei appear in the accessible sources; as far as the literature shows, it has never been bred or studied in captivity. What follows is drawn from the well-documented reproductive biology of the rainbowfish family — genus-typical inference, not confirmed for this species.
Rainbowfishes, Chilatherina among them, are egg-scattering plant-spawners with no parental care. Males are more colourful and competitive, staking out display areas and courting females with heightened colour and fin-flaring, often most active in the early morning. A receptive female follows a displaying male into fine vegetation, where the pair release eggs that attach to the substrate by fine adhesive filaments.
Because no spawning of C. pricei has been documented, the timing, triggers, and any species-specific courtship signals remain unknown and are not asserted here.
Breeding
There is no published account of Chilatherina pricei being bred in captivity, and the species is essentially unknown in the aquarium hobby. Detailed, species-specific breeding data are therefore unavailable, and none is invented here.
Where rainbowfishes of this family have been bred, the pattern holds: conditioned adults deposit small adhesive eggs onto fine-leaved plants or spawning mops over a long stretch, releasing a few eggs at a time across many days rather than one clutch. The eggs hang by filaments and hatch after roughly one to two weeks at typical tropical temperatures; the parents give no care and will eat eggs and fry. The tiny fry need very small first foods — infusoria or commercial liquid fry food — before moving up to newly hatched brine shrimp.
All of that is extrapolated from family biology, not observed in C. pricei. Anyone who got hold of this rarely seen fish would be working out its captive breeding from scratch.
In the aquarium
Chilatherina pricei is, for practical purposes, not an aquarium fish: it is a narrow-range New Guinea endemic with little to no presence in the ornamental trade and no dedicated hobby care literature. The notes here are genus-typical inference for anyone who might encounter it, not documented husbandry for this species.
Care across Chilatherina points to warm tropical freshwater and an active, shoaling midwater fish that wants a group and a long, open swimming lane. Given the rheophilic, rocky-channel origin, well-oxygenated water with gentle to moderate flow and a clean, stable setup would suit it better than still, soft blackwater. Precise temperature and chemistry targets for C. pricei aren't in the available sources, so I won't invent numbers.
Like any rainbowfish, it would do best in a school with peaceful, similarly sized companions. The honest read, though, is that this is a wild, little-studied fish rather than an established aquarium subject, and any keeping advice here is provisional.
Conservation
Chilatherina pricei is assessed as Vulnerable (VU) on the IUCN Red List, under criterion D2, in an assessment dated 3 December 2019 (published in 2020; assessment ID 161080365). The D2 criterion applies to species with a very restricted area of occupancy or a small number of locations, making them susceptible to the effects of plausible future threats that could rapidly drive the species to a more threatened category or to extinction.
The listing turns on extreme narrow-range endemism: confined to the Reifafeif River system in Papua, Indonesia, with no large outlying populations to buffer it against local disturbance. For a fish living in a single small river, habitat alteration, pollution, or an introduced species could hit a large share of the global population at once.
Within that range the species is reported as locally abundant, which helps, but abundance in one river doesn't offset the risk of having nowhere else to live. As with much of New Guinea's freshwater fauna, continued survey and habitat protection are the conservation needs.