Satanoperca leucosticta (MÜLLER & TROSCHEL, 1849)

Whitespot Eartheater

SynonymsTop ↑

Geophagus leucostictus Müller & Troschel, 1849; Satanoperca macrolepis Günther, 1862

Etymology

Satanoperca: from the Ancient Greek Σατάν (Satán), meaning ‘Satan’ (the devil), and πέρκη (pérkē), meaning ‘perch’.

leucosticta: from the Ancient Greek λευκός (leukós), meaning ‘white’, and στικτóς (stiktos), meaning ‘spotted’, presumably in reference to the colour pattern on the body and head in this species.

Classification

Order: Perciformes Family: Cichlidae

Distribution

Native to the Guiana Shield in eastern Venezuela (rivers draining into Guyana from Bolivar state), Guyana (throughout the country), northwestern Suriname (Nickerie and Sipaliwini districts), and northern Brazil (Roraima state). It is known with certainty from the Essequibo, Demerara, Nickerie, and Branco river systems, but  in the Guianas is also likely to occur in the Cuyuni, Mazaruni, Berbice, and Courantyne/Corantijn watersheds.

It appears to have infiltrated the rio Branco via the rio Takutu, an affluent system which becomes hydrologically connected to the Rupununi River, a tributary in the upper Essequibo basin, during the wettest two months of the year, when a large area of low-lying savannah which lies between the two becomes flooded and is known as Lake Amukú.

Type locality is not given in the original description although the specimens are assumed to have been collected from the Rupununi River.

Habitat

Has been observed in main river channels, smaller tributaries and floodplain lakes, typically over substrates of sand or mud with patches of leaf litter and submerged tree branches.

Maximum Standard Length

130 – 150 mm.

Aquarium SizeTop ↑

An aquarium with a base measuring at least 180 ∗ 60 cm or equivalent is required.

Maintenance

The most essential item of décor is a soft, sandy substrate so that the fish can browse naturally (see ‘Diet’).

Coarser materials such as gravel or small pebbles can inhibit feeding, damage gill filaments and even be ingested with the potential of internal damage or blockages.

Additional furnishings are as much a case of personal taste as anything else but the most favoured set-ups tend to feature relatively dim lighting plus some chunks of driftwood and scattered roots or branches.

Leaf litter is a typical feature of the natural environment but not really recommended in aquaria because the feeding behaviour of Satanoperca spp. tends to cause an excess of partially-decomposed material in suspension which not only looks unsightly but can block filter and pump mechanisms.

Water quality is of the utmost importance since these cichlids are extremely susceptible to deteriorating water quality and swings in chemical parameters so should never be introduced to a biologically immature aquarium. S. daemon also requires soft, acidic conditions and in most cases will not thrive in untreated tap water.

The best way to achieve the desired stability is to filter the tank using a combination of external canister filters and/or a sump system and perform minimum weekly water changes of 50-70%.

If the maintenance regime is insufficient health issues such as head and lateral line erosion or stunted growth can occur.

Mechanical filtration should also be tailored to trap small particles stirred up by the fish as sand can cause blockages and wearing issues with filter mechanisms if allowed to continually run through the system. High flow rates should be avoided so position filter returns accordingly.

Water Conditions

Temperature: 20 – 28 °C

pH: 5.5 – 7.5

Hardness: 36 – 215 ppm

Diet

Satanoperca spp. are benthophagous by nature, employing a method of feeding whereby mouthfuls of substrate are taken and sifted for edible items with the remaining material expelled via the gill openings and mouth. For this reason they are commonly termed ‘eartheaters’ and the provision of a suitable substrate is essential to their long-term well-being. Once settled they readily rise into the water column when food is introduced but continue to browse normally at other times.

The stomach contents of wild specimens mostly comprise small aquatic and terrestrial invertebrates including cladocerans, ostracods, and insect larvae (particularly chironomids), plus plant material (seeds), organic detritus and sediment.

Even large individuals seem unable to properly ingest larger food items, meaning the diet should contain a variety of high quality, fine-grade prepared foods plus small live or frozen bloodworm, Tubifex, Artemia, mosquito larvae, etc. At least some of the dried products should contain a high proportion of vegetable matter such as Spirulina or similar.

Home-made, gelatine-bound recipes containing a mixture of dried fish food, puréed shellfish, fresh fruit and vegetables, for example, are proven to work well and can be cut into bite-sized discs using the end of a sharp pipette or small knife.

Rather than a single large meal offer 3-4 smaller portions daily to allow natural browsing behaviour as this seems to result in the best growth rate and condition.

Behaviour and CompatibilityTop ↑

Unless breeding this species is surprisingly peaceful and will not predate on fishes larger than a few millimetres in length. Suitable tankmates are numerous and include most peaceful species enjoying similar environmental conditions. Best avoided are aggressive or territorial substrate-dwelling species, or those requiring less acidic or mineral-rich water.

Some aquarists keep Satanoperca spp. alongside freshwater stingrays of the genus Potamotrygon which in many cases has proven successful but in some has resulted in the cichlids disappearing at night.

S. leucosticta is gregarious and tends to exist in loose aggregations unless spawning, with juveniles in particular displaying strong grouping instincts. A group of 5-8 individuals should be the minimum purchase and these will form a noticeable dominance hierarchy. When maintained in smaller numbers weaker specimens can become the target of excessive antagonism by dominant individuals or the group may fail to settle and behave nervously.

Sexual Dimorphism

Very few external differences have been observed, although adult males tend to grow somewhat larger than the slightly deeper-bodied females.

Reproduction

This species is a larvophilous maternal mouthbrooder that has been bred in aquaria, although at least one putatively conspecific wild form is an ovophilous mouthbrooder (see ‘Notes’).

There does not appear to be any particular trigger for the spawning process in either case, with the main requirements being good diet and stringent maintenance regime involving relatively large weekly water changes.

Since accurate sexing is very difficult it is perhaps best to begin with a group of young fish and allow pairs to form naturally, while a degree of patience is also required since it can be at least a year, often two or more, until they become sexually mature.

Courtship is initiated by the male, with nuptial individuals forming territories which are typically centred around a piece of driftwood,  sunken leaf, or other submerged object. Gravid females are courted and when a pair forms they may defend the territory together for a few days prior to spawning. Other fishes, especially conspecifics, are not tolerated in the vicinity and in smaller aquaria may need to be removed.

Eggs are deposited in small batches and once fertilised the larvophilous forms tend to cover the brood with a thin layer of substrate. The female then remains to guard and tend the eggs while the male protects the surrounding territory. The eggs hatch in 36-48 hours and the larvae are picked up by the female, normally remaining in her buccal cavity for a further 7 or 8 days. In the ovophilous form, the eggs are instead collected by the female as soon as they are fertilised and she carries them for approximately 9 days. Some males lose interest in territorial defence once the female is brooding the eggs and may attack their partner, so careful observation and readiness for evasive action are required.

Once the fry are free swimming they are easily-fed, accepting good quality powdered dry foods, Artemia nauplii, microworm, etc. If maintained with the female brood care tends to continue for a further 3-4 weeks, and should the male may remain peaceful he may also continue to participate.

If maintaining the adults in a community situation it may prove best to remove brooding females since the fry become easy prey for other fishes, including conspecifics, once released.

NotesTop ↑

S. leucosticta is frequently available in the ornamental trade and farmed for the purpose in several countries. It is often confused with its congener S. jurupari in aquarium literature and on websites, but is easily recognised by presence (vs. absence) of prominent white spots or vermiform markings on the sides of the head.

Although the presence of white spots on the head does not distinguish it from all known Satanoperca populations (see below), it can at least be separated from all nominal congeners by the following combination of characters: presence of a relatively small dark ocellus on the upper caudal-fin base; absence of well-defined dark blotches on the sides of the body (although some forms do display dark  markings on the body when stressed or sleeping); presence of small or large white spots on the sides of the head; absence of black spots at the base of the dorsal-fin; absence of a dark lateral stripe on the body.

The precise identity of S. leucosticta is a confusing issue, however, with differences in colour pattern (presence or absence of a reddish stripe in the dorsal portion of the body, variable fin colouration, extent of pale or iridescent markings on the head, body and fins, etc.) and morphological characters observed across its range, and possible conspecific forms with similar white spots and vermiculations on the head inhabiting the Branco, Negro, and upper Orinoco river basins.

Among these, the congener S. mapiritensis (Fernández-Yépez 1950) from the middle and lower Orinoco grouped most closely with S. jurupari and was clearly distinct from S. leucosticta in recent genetic analyses. A form with white spots on the head (but crucially, not the gill covers) from the upper Negro, Casiquiare, and upper Orinoco basins in Brazil, Colombia, and Venezuela was not included, however, nor was a Brazilian population purportedly from the rio Branco and lower rio Negro. The latter is known as S. sp. ‘Amazonas red’ in the aquarium hobby, and exhibits an ovophilous, rather than larvophilous, reproductive strategy. Here on SF such unidentified forms will be included in this profile as S. cf. leucosticta until their identities can be established, since the possibility that they form a single meta-population with S. leucosticta in the Orinoco-Casiquiare-Negro system (as may be the case for  a group comprising S. jurupari, S. mapiritensis and a form known to aquarists as S. sp. ‘alto-negro’) cannot currently be ruled out.

Satanoperca was considered a synonym of Geophagus for a number of decades before being revalidated by Kullander (1986). It is separated from all other members of the putative cichlid subfamily Geophaginae by presence of a small ocellated spot at the upper caudal-fin base, and from Geophagus by a number of morphological characters as follows: equal numbers of abdominal and caudal vertebrae or one more abdominal vertebra (vs. more caudal than abdominal vertebrae in Geophagus); no ribs on caudal vertebrae and no postabdominal swimbladder extensions (vs. presence of both in Geophagus; cheek scaled rostrally to centre (vs. naked on anterior half; dorsal and anal fins naked (vs. scaled); external gill rakers on lower limb of first gill arch attached to the skin covering the gill filaments (vs. attached to ceratobranchial skin); jaw dentition reduced to one or two short series in each jaw (vs. pluriseriate with wide band of inner teeth); absence (vs. presence) of tooth plates on 4th ceratobranchial; presence (vs. absence) of an ocellus on caudal-fin base; both or only upper lip fold continuous (vs. both interrupted anteriorly); preoperculum and supracleithrum frequently serrated (vs. entire); absence (vs. presence) of median hypural cartilage; 3 (vs. 4) infraorbitals.

The genus is likely to contain additional species, and has been separated into three groups with distinctive morphology, namely the S. jurupari group, the S. daemon group, and the monotypic S. acuticeps group.

Among these, members of the S. jurupari group are characterised by a colour pattern comprising a dark lateral stripe or row of blotches along the side of the body, normally XV.10 (XIV-XVII.8-11) dorsal-fin rays, normally 27 (26-28) E1 scales (the longitudinal row immediately above the lower lateral line, excluding the pectoral girdle), and 12-18 rakers on the first gill arch.

S. daemon group members grow larger than other congeners, possess one or two large dark blotches on the side of the body and a prominent ocellus at the upper caudal-fin base, usually XIX.13 (XII-XIV.12-14) dorsal-fin rays, 29-31 E1 scales, and 18-22 gill rakers. S. acuticeps is unique in that it has a relatively more terminal mouth than all other genus members, normally XIII.12 (XIII.11-12) dorsal-fin rays, 27-28 E1 scales, and 17-20 gill rakers.

The groups also differ in reproductive strategy, with the S. daemon and S. acuticeps assemblages being substrate spawners, and the S. jurupari group mouthbrooders.

Satanoperca and a number of related genera are often included in the putative subfamily Geophaginae, and Kullander (1998) conducted a morphology-based phylogenetic study in which the neotropical Cichlidae was divided into six subfamilies of which the Geophaginae contained 16 genera divided among three ‘tribes’:

Acarichthyini – Acarichthys and Guianacara.
Crenicaratini – Biotoecus, Crenicara, Dicrossus and Mazarunia.
Geophagini – Geophagus, Mikrogeophagus, ‘Geophagus‘ brasiliensis group, ‘Geophagus‘ steindachneri group, Gymnogeophagus, Satanoperca, Biotodoma, Apistogramma, Apistogrammoides and Taeniacara.

Later molecular studies by Farias et al. (1999, 2000, 2001) resulted in the additions of Crenicichla and Teleocichla to the Geophaginae, a result supported by López-Fernández et al. (2005) who conducted the most detailed molecular analysis of the grouping to date including 16 of the 18 genera and 30 species.

However their conclusions regarding interrelationships between genera did vary somewhat from previous hypotheses and can be summarised by the following loosely-defined groups:

– a weakly-supported sister group relationship between Acarichthys and Guianacara.
– a well-supported ‘Satanoperca clade’ comprising Satanoperca, Apistogramma, Apistogrammoides and Taeniacara.
– a ‘big clade’ with Geophagus, Mikrogeophagus, ‘Geophagus‘ brasiliensis group, ‘Geophagus‘ steindachneri group, Gymnogeophagus, Biotodoma, Crenicara and Dicrossus.
– a ‘crenicarine clade’ with Biotoecus and Crenicichla.

No representatives of Teleocichla or Mazarunia were included in the study but the former is well-established as sister to Crenicichla while the latter has grouped closely with Dicrossus and Crenicara in earlier works.

The other main conclusions of the paper are confirmation that Geophaginae is a monophyletic group exhibiting strong signs of having undergone rapid adaptive radiation.

References

1. Müller, J. and F. H. Troschel , 1849 - Versuch einer Fauna und Flora von Britisch-Guiana v. 3, Berlin: 618-644
   Fische. In: Reisen in Britisch-Guiana in den Jahren 1840-44. Im Auftrag Sr. Mäjestat des Königs von Preussen ausgeführt von Richard Schomburgk.
2. de Souza, L. S., J. W Armbruster, and D. C. Werneke, 2012 - Cybium 36(1): 31-43
   The influence of the Rupununi portal on distribution of freshwater fish in the Rupununi district, Guyana.
3. Gosse, J.-P., 1976 - Académie Royal des Sciences d'Outre-Mer, Cl. Sci. Nat. Méd. (N. S.) 19(3): 1-173
   Révision du genre Geophagus (Pisces Cichlidae).
4. Kullander, S. O., 2012 - Cybium 36(1): 247-262
   A taxonomic review of Satanoperca (Teleostei: Cichlidae) from French Guiana, South America, with description of a new species.
5. Kullander, S. O., 1986 - Swedish Museum of Natural History: 1-431
   Cichlid fishes of the Amazon River drainage of Peru.
6. Kullander, S. O., 1998 - EDIPUCRS, Porto Alegre: 461-498
   A phylogeny and classification of the South American Cichlidae (Teleostei: Perciformes). In: Malabarba, L. R. , R. E. Reis, R. P. Vari, Z. M. S. de Lucena and C. A. S. Lucena (eds). Phylogeny and classification of Neotropical fishes.
7. Kullander, S. O. and E. J. G. Ferreira, 1988 - Cybium 12(4): 343-355
   A new Satanoperca species (Teleostei, Cichlidae) from the Amazon River basin in Brazil.
8. Kullander, S. O. and H. Nijssen, 1989 - E. J. Brill, Leiden: i-xxxii + 1-256
   The cichlids of Surinam. Teleostei: Labroidei.
9. López-Fernández, H., R. L. Honeycutt, and K. O. Winemiller, 2005 - Molecular Phylogenetics and Evolution 34(1): 227-244
   Molecular phylogeny and evidence for an adaptive radiation of geophagine cichlids from South America (Perciformes: Labroidei).
10. Machado-Allison, A., B. Chernoff, R. Royero-León, F. Mago-Leccia, J. Velázquez, C. Lasso, H. López-Rojas, A. Bonilla-Rivero, F. Provenzano, and C. Silvera, 2000 - Interciencia 25(1): 13-21
    Ictiofauna de la cuenca del río Cuyuni en Venezuela.
11. Reis, R. E., S. O. Kullander and C. J. Ferraris, Jr. (eds), 2003 - EDIPUCRS, Porto Alegre: i-xi + 1-729
    Check list of the freshwater fishes of South and Central America. CLOFFSCA.
12. Willis S. C., H. López-Fernández, C. G. Montaña, I. P. Farias, and G. Ortí, 2012 - Molecular Phylogenetics and Evolution 63(3): 798-808
    Species-level phylogeny of ‘Satan’s perches’ based on discordant gene trees (Teleostei: Cichlidae: Satanoperca Günther 1862).