Taxonomy & naming
Teleocichla centisquama was described in 2002 by the Brazilian ichthyologists Jansen Zuanon and Ivan Sazima, in Ichthyological Exploration of Freshwaters (volume 13, number 4, pages 373–378), from material collected in the rapids of the lower Rio Xingu near Altamira, Pará. The holotype (INPA 14934) is housed at the Instituto Nacional de Pesquisas da Amazônia in Manaus, with paratypes distributed between INPA, the Museu de Zoologia da Universidade de São Paulo (MZUSP) and the Universidade Estadual de Campinas (ZUEC); the type locality is Furo do Zé Pinheiro (3°27'26"S, 51°55'03"W) on the Rio Xingu. The species had been known to ichthyologists for some years before its formal description — during 1996–1997 field surveys it was tracked under the field code 'Teleocichla LS,' one of three undescribed forms studied alongside the genus's named species. The genus Teleocichla itself was erected by the Swedish ichthyologist Sven Kullander in 1988 for a then-novel assemblage of rheophilic cichlids from the rocky rivers of the Brazilian Shield, and centisquama was its first addition after the original six species. It sits firmly within the genus on morphological grounds, and Teleocichla in turn belongs to the eartheater tribe Geophagini of the American-cichlid subfamily Cichlinae, where it is allied with — and effectively a small-mouthed offshoot of — the pike cichlids Crenicichla. No synonyms exist; the name has been treated as valid in every subsequent revision, including Kullander's 2003 checklist of South American cichlids and the genus-wide work of Varella and colleagues (2016, 2023). It should not be confused with the superficially similar Teleocichla preta, the large dark 'black' Xingu species described separately in 2016; centisquama is a paler, station-holding fish of the open rock tops.
Morphology
This is a small cichlid: the type series tops out at about 1.5 in standard length, making it one of the more modest members of the genus. The body is strongly elongate and almost cylindrical in cross-section — body depth is only about 10.5–13.9% of standard length — tapering to a rounded caudal fin, the classic 'goby-like' silhouette shared by all Teleocichla and convergent on the African rapids cichlids of the genus Teleogramma. The long dorsal fin carries 18–20 spines and 9–11 soft rays, the anal fin 3 spines and 8–9 soft rays, and there are 33 vertebrae. The diagnostic feature that gives the fish its name is its squamation: an unusually high count of 113–129 scales along an unbroken (continuous) lateral line, the most of any species in the genus, with ctenoid (rough-edged) scales restricted to the posterior quarter of the body. Compared with its congeners it has a smaller eye (orbital diameter 5.7–7.6% of standard length, against 7.3–10.6% in others) and a shallower caudal peduncle. The pectoral fins are nearly symmetrical with a slightly thickened lower edge — an adaptation for bracing against current. Coloration is drab and cryptic, matching the rock and detritus of its habitat; territorial individuals can intensify their patterning, but this is not a brightly marked fish. Sexual dimorphism in Teleocichla is generally subtle: as in related species, males tend to grow somewhat larger and develop more extended, better-coloured median fins, while ripe females are rounder-bodied, but no strong, reliably published dimorphic marker has been documented specifically for this species.
Habitat
Teleocichla centisquama is endemic to the Rio Xingu in Pará, Brazil, where it is confined to the rocky rapids of the river's lower reaches — by the IUCN's account, from the mouth of the Rio Iriri downstream through the great horseshoe bend known as the Volta Grande do Xingu. This is clearwater country: the Xingu drains the ancient, nutrient-poor crystalline rock of the Brazilian Shield and runs warm, low in dissolved minerals, slightly acidic to near-neutral, and seasonally transparent. The fish is obligately rheophilic, living among and on top of boulders in flowing water with current velocities measured up to about 1.7 metres per second — flows that would tumble most fish but in which Teleocichla holds its ground. Like other members of the genus it has a reduced swim bladder and negative buoyancy, so rather than swimming in open water it perches on the substrate, bracing with thickened pectoral fins and darting between rocks in short bursts. Whereas crevice-dwelling relatives wedge themselves into cracks, centisquama is a station-holder that characteristically sits exposed atop large rocks in the fastest water. Recorded depths are shallow — these are fish of the photic rapids zone, typically within a metre or two of the surface over rock, the band that field workers can snorkel — and in the dry season, when the rapids shrink, water temperatures in this habitat run warm, broadly in the upper twenties to low thirties Celsius. Hard in-situ chemistry specific to this species is sparse in the literature, but the Xingu rapids generally combine soft, warm, oxygen-rich, slightly acidic clearwater with a hard rock substrate.
Feeding
The hallmark of the genus Teleocichla, and the key to its success in the rapids, is not the rheophilic body alone but the mouth: small and terminal, more like that of a marine dragonet (Callionymidae) than the gaping jaws of a predatory pike cichlid. This 'callionymid mouth' lets Teleocichla exploit a fine-grained food niche in fast water that the larger-mouthed Crenicichla cannot. Teleocichla centisquama forages directly on rock surfaces, picking mostly benthic prey from the stone. The published diet is a menu of small rapids invertebrates: micro-crustaceans (cladocerans, ostracods and copepods), the immature stages of aquatic insects (chironomid midge larvae, mayfly and caddisfly nymphs), and minute clams. It is, in effect, a specialized micro-predator and grazer of the aufwuchs and interstitial fauna that coat the boulders — a low trophic-level fish (FishBase estimates a trophic level near 3.2) whose feeding is inseparable from the rock-and-current microhabitat it occupies. Differences in body shape, microhabitat use and diet among the several Teleocichla species sharing the Xingu rapids are thought to be exactly what allows so many close relatives to coexist there.
Mating
Reproductive behaviour in Teleocichla centisquama has not been documented in detail, and what can be said is drawn largely from the genus and from field observation of related Xingu species. Teleocichla are territorial, substrate-bound fish: individuals — most conspicuously territory-holding males with their fins fanned and colours raised — defend small patches of rock, pits, holes or crevices, and territoriality intensifies around breeding. In several congeners, larger dominant fish have been seen sharing a territory with one or more smaller, plainer individuals (presumed females or juveniles), hinting at pair- or harem-based associations rather than open shoaling. Because centisquama is a comparatively exposed station-holder rather than a crevice specialist, its courtship presumably plays out on and around the boulder tops it occupies. Reproductive isolation among the syntopic Xingu Teleocichla is thought to be maintained not by spatial separation — several species can occur under the same rock — but by behavioural barriers such as courtship displays, colour and timing. Beyond that, the specifics of pair formation and spawning ritual in this particular species remain unrecorded.
Breeding
No spawning of Teleocichla centisquama has been described from the wild or, in any detailed published account, from captivity, so its breeding biology is inferred from the genus. Teleocichla are cave or crevice substrate spawners: like their pike-cichlid relatives and like the convergent African rheophilic genera, they deposit adhesive eggs on a concealed hard surface — the wall or ceiling of a rock cavity, crevice or hollow under a boulder — rather than building open nests. Parental care in the genus is biparental to maternal, with the eggs and larvae guarded inside the shelter; clutches are small, as befits tiny fish (congeneric rapids cichlids of this size are reported to lay on the order of a few dozen to perhaps a hundred eggs), and the fry are guarded within the rocky refuge until they can fend for themselves in the current. Spawning is presumably tied to the river's seasonal rhythm, most plausibly to the falling-water and low-water period when the rapids are most extensive and accessible and territories are densest. For centisquama specifically, clutch size, egg number, developmental timing and the division of parental labour are all genuinely undocumented, and any figure should be read as a genus-typical estimate rather than a measured value.
In the aquarium
Teleocichla as a group reach the hobby only sporadically, as a specialist's fish exported in small numbers from the Xingu, and Teleocichla centisquama is a rarity even among them; it has no established common name and is sold, when it appears at all, under its scientific name or a collector's code. It is emphatically not a beginner's cichlid, and almost everything about keeping it follows from one fact: it is a small fish built for fast, clean, oxygen-saturated water on bare rock.
The defining requirement is flow. These fish come from rapids and need strong, well-oxygenated current — achieved in aquaria with oversized circulation pumps or powerheads aimed across a rocky hardscape, the kind of 'river tank' set-up used for hillstream loaches and other rheophilic specialists — rather than the still water of a typical community aquarium. Because the fish is bottom-oriented and territorial rather than far-ranging, footprint and structure matter more than sheer volume: a tank of roughly 31.5–39.5 in length with a generous floor area and abundant rockwork gives a small group the broken sightlines and individual territories they need. The aquascape should be built from rounded boulders, cobbles and flat stones stacked to create caves, crevices and current-swept rock tops, over a substrate of sand and smooth pebbles; plants are largely irrelevant to a fish of the bare-rock rapids.
Water should mirror the Xingu: warm (around 79–90 °F), soft, and slightly acidic to neutral (pH roughly 6.0–7.5), kept scrupulously clean and high in dissolved oxygen. Teleocichla are intolerant of accumulated waste and low oxygen, so heavy biological filtration, vigorous surface agitation and frequent water changes are not optional. Feed small, meaty foods that suit a micro-predator's mouth — live and frozen bloodworm, daphnia, cyclops, brine shrimp and the like — offered so they are carried in the current to fish that pick rather than chase; many specimens are slow to take dry foods.
Temperament is the other catch. Like its relatives, centisquama is territorial and can be sharply intraspecifically aggressive in close quarters, so a group needs enough rock-divided space to spread out, and tankmates should be other small, current-tolerant rapids species rather than slow or delicate fish. Kept in a true river tank by an experienced aquarist, it is a characterful fish that perches and patrols its own patch of rock; kept in a placid, under-oxygenated community tank, it will not thrive. Given its conservation status and limited availability, it is best regarded as a fish for dedicated rheophile keepers.
Conservation
Teleocichla centisquama is assessed by the IUCN Red List as Vulnerable (VU, criterion B2ab(ii,iii)), in an assessment dated 7 November 2018 carried out by Brazil's Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio). The listing reflects a small, fragmented range and ongoing habitat loss driven explicitly by hydropower and dam-related water management. The reason is the Belo Monte hydroelectric complex, whose operation diverts much of the Xingu's flow out of the Volta Grande — the exact stretch of rapids to which this fish is endemic — and into a power canal, leaving a roughly 100-km 'reduced-flow' reach where the natural flood pulse has been replaced by an artificial, dam-controlled hydrograph. For an obligate rapids fish that depends on fast current over rock, the dewatering and altered seasonal flooding of those rapids is an existential pressure: it degrades and shrinks the precise microhabitat the species cannot live without. Independent monitoring after the dam came online has documented declining fish richness and abundance in the affected lotic (flowing-water) habitats of the lower Xingu, alongside fish kills linked to the manipulated flow. Teleocichla centisquama is thus one of a cluster of narrowly endemic Xingu rapids fishes — cichlids, plecos and characins among them — whose conservation outlook is tied directly to how much of the river's natural flow is allowed back into the Volta Grande. It carries no CITES listing, and while it is taken in small numbers for the ornamental trade, habitat alteration, not collection, is the documented threat.