Cichlasoma Swainson

Synonymy

Plesiops (Cichlasoma) Swainson, 1839. Nat. Hist. Fish. 2, p. 230 (type by monotypy Labrus punctatus Bloch 'pl. 295, fig. 1' = Labrus bimaculatus Linnaeus; set aside by Opinion 1954, designating Labrus bimaculatus Linnaeus, 1758 as type species). Neuter.
Plesiops (Cichlaurus) Swainson, 1839. Nat. Hist. Fish. 2, p. 173 (variant spelling of Plesiops (Cichlasoma)). Masculine.
Cichlosoma Regan, 1905. Ann. Mag. nat. Hist. (7) 16, p. 61 (unjustified emendation of Cichlasoma). Neuter.

Cichlasoma dimerus (Heckel) guarding young in aquarium. Photo: A. Kullander.

Diagnosis

Cichlasoma species are distinguished from other large-scaled cichlasomines by characters in combination. Except that two bars may be merged in C. paranaense and C. sancifranciscense, there are six vertical bars over the sides from the midlateral spot caudad, instead of five or less. The dorsal and anal fin bases are more or less extensively scaled in contrast to Aequidens, Krobia, Bujurquina, Tahuantinsuyoa, most Laetacara, and Nannacara. In overall appearance Cichlasoma species are similar in particular to Aequidens species, e.g., in having a light-ringed spot at the base of the caudal fin, in having a dark spot on the cheek close to the orbit, and in having an asymmetrical spot-pattern in the caudal fin.

Standard length rarely exceeds 100 mm in the wild.

Included species

Cichlasoma amazonarum Kullander, 1983

Cichlasoma amazonarum Kullander, 1983. Revision Cichlasoma, p. 115, pl. V, fig. 2 (Peru, depto Loreto, R. Ampiyacu system, little upstreams of Pebas, Sacarita del Tuyé, right bank tributary of the R. Ampiyacu, floating meadow near mouth).

Cichlasoma araguaiense Kullander, 1983

Cichlasoma araguaiense Kullander, 1983. Revision Cichlasoma, p. 252, pl. XIV, fig. 1 (Brasil, est. Mato Grosso, R. Araguaia system, small igarapé tributary to Igarapé Sangadina, tributary to the R. das Mortes, 1 km from Xavantina).

Cichlasoma bimaculatum (Linnaeus, 1758)

Labrus bimaculatus Linnaeus, 1758. Syst. Nat. ed. 10, 1, p. 285 (M. Mediterraneo).
Acara Gronovii Heckel, 1840. Annln wien. Mus. Natges. 2, p. 361 (Flüsse in Surinam).
Sparus filamentosus Gray, 1854. Catal. Fish. Gronow, p. 60 (Surinami).

Cichlasoma boliviense Kullander, 1983

Cichlasoma boliviense Kullander, 1983. Revision Cichlasoma, p. 165, pl. VIII, fig. 2 (Bolivia, depto Santa Cruz, R. Guaporé system, R. Uruguaito, tributary of the R. Quizer, 13 km S San Xavier).

Cichlasoma dimerus (Heckel, 1840)

Acara dimerus Heckel, 1840. Annln wien. Mus. Natges. 2, p. 351 (Cujabà-Fluss).
Acara marginatus Heckel, 1840. Annln Wien Mus. Natges. 2, p. 350 (der Nähe von Cujabà).
?Heros centralis Holmberg, 1891. Revta Argent. Hist. nat. 1, p. 183 (República Argentina, Provincia de Santiago del Estero).

Cichlasoma orientale Kullander, 1983

Cichlasoma orientale Kullander, 1983. Revision Cichlasoma, p. 177, pl. IX, fig. 1 (Brasil, est. Ceará, R. Curu system, Pentecoste, reservoir).

Cichlasoma orinocense Kullander, 1983

Cichlasoma orinocense Kullander, 1983. Revision Cichlasoma, p. 106, pl. IV, fig. 2 (Colombia, depto Meta, R. Meta system, Laguna Mozambique, at shoreline on N side of lake).

Cichlasoma paranaense Kullander, 1983

Cichlasoma paranaense Kullander, 1983. Revision Cichlasoma, p. 241, pl. XIII, fig. 1 (Brasil, Est. Mato Grosso do Sul, R. Paraná superior system, mun. Tres Lagoas, varzea on the left bank of the R. Sucuriú, at Fazenda Santa Luzia, near Urubupungá dam).

Cichlasoma portalegrense (Hensel, 1870)

Acara portalegrensis Hensel, 1870. Arch. Natges. 36, p. 52 (bei Porto Alegre in stagnirenden Gewässern).

Cichlasoma pusillum Kullander, 1983

Cichlasoma pusillum Kullander, 1983. Revision Cichlasoma, p. 221, pl. XII, fig. 1 (Paraguay, depto Alto Paraná, R. Alto Paraná system, Puerto Palma).

Cichlasoma santifranciscense Kullander, 1983

Cichlasoma sanctifranciscense Kullander, 1983. Revision Cichlasoma, p. 227, pl. XII, fig. 2 (Brasil, Est. Bahia, R. São Francisco system, Lagoa Viana).

Cichlasoma taenia (Bennett, 1831)

Chromis Taenia Bennett, 1831. Proc. Comm. Sci. Corr. zool. Soc. Lond. 1, p. 112 (Apud Trinidad).

Key to species

From Kullander (1983), slightly modified.

1. Three anal-fin spines..........................2
Four to 8 anal fin spines......................7

2.Mostly uniserial predorsal scale pattern; Bars 2+3 usually merged; caudal fin immaculate; Rio Paraná superior................C. paranaense
Predorsal scale pattern triserial; Bars 1-6 separate entities; caudal fin extensively spotted or immaculate..........................3

3. Caudal fin immaculate; prepelvic scales cycloid; head narrow (18.2-20.6% of SL); Rio Tocantins and Rio Xingu.....................C. araguaiense
Caudal fin extensively spotted; prepelvic scales ctenoid at least in adults; head wide (18.5-22.5% of SL).............................4

4. Dark rim on nape and dorsal side scales incon- spicuous; commonly mottled pattern on posterior sides, formed by dark spots on scale bases; interradial dorsal fin scales in double rows in adults; Bolivian Amazonia..........C. boliviense
Dark rim on nape and dorsal scales prominent and wide; interradial dorsal-fin scales in single row on each memberane; no mottled pattern formed by scale base spots on posterior sides..5

5. Anterior lateral band as intense as midlateral spot; black spots on gill-cover and cheek spot enlarged; prepelvic angle 20-25°; upper Rio Alto Parana and Rio Uruguay..........C. pusillum
Anterior lateral band usually fainter than mid- lateral spot; no black spots on gill cover, and cheek spot small; prepelvic angle 25-34°.......6

6. Spot pattern on dorsal lobe of caudal fin distinct; anterior lateral band fainter than midlateral spot; lower jaw teeth 16-24 in outer hemiseries; Rio Paraguay, lower Rio Alto Parana, Parana medio and Parana inferior......C. dimerus
Hyaline interspaces dominating over spot pattern in dorsal lobe of caudal fin; anterior lateral band as intense as or fainter than mid- lateral spot; 11-15 teeth in lower jaw outer hemiseries; coast of Rio Grande do Sul.......... ................................C. portalegrense

7. Slender, stick-like first pharyngobranchial bone; caudal fin immaculate; Bars 2+3 usually merged; predorsal scale pattern uniserial; Rio São Francisco system, coastal drainages near Salvador, Lago de Parnaguá.C. sanctifranciscense
First pharyngobranchial bone widened ventrally; caudal fin usually spotted; Bars 1-6 separate; predorsal scale pattern triserial..............8

8. Posterior lateral band and scale base spots close to soft dorsal-fin base usually well developed; dorsal fin interradial scales in single rows, up to 5, width of scaly layer to 1/4 of length of last dorsal-finn spine; caudal fin immaculate or with sparse dotting on obscure ground; northeastern Brazil.C. orientale
Posterior lateral band rarely prominent; dorsal posterior side scale-base spots absent or not especially distinct; dorsal fin with double or single series of interradial scales; width of scaly layer usually 1/3 or more length of last dorsal-fin spines; caudal fin with distinct dark dots with contrasting light interspaces..9

9. Head(20.8-23.1 % of SL) and interorbital space (14.0-17.3% of SL) wide; interradial dorsal-fin scales usually in double rows, 5-20 along a membrane, depth of scaly layer half or more length of last dorsal-fin spine; Amazon basin except Bolivia....................C. amazonarum
Head and interorbital width variable; dorsal-fin squamation reduced (interradial scales in single series, up to five) depth of scaly layer at most about 1/3 length of last dorsal- fin spine....................................10

10. Dorsal-fin base length 64.0-68.3% of SL; depth 48.0-52.9% of SL; caudal-fin spotting in excurved series; Orinoco drainage......... ..................................C. orinocense
Dorsal-fin base length 56.7-67.8% of SL; depth 38.8-57.5% of SL; caudal-fin spotting asymmetrical .................................11

11. Body depth 44.4-57.6% of SL; no supraorbital spot; Guianas, Rio Branco ........C. bimaculatum
Body depth 38.8-49.2% of SL; supraorbital spot usually well evident; Trinidad, Rio Monagas .......C. taenia

Cichlasoma portalegrense (Hensel), field photo taken near Porto Alegre. Photo: A. Kullander.

Etymology

The second word in Cichlasoma and Cichlosoma is evidently from the Greek soma, body. In Cichlaurus the second part is probably from the Greek oura, tail. Cichla- probably refers to the generic name Cichla (Greek kichle). There is, however, no really close similarity between Cichlasoma and Cichla in body or caudal fin shape. Swainson (1839) explicitly referred to the rounded caudal fin shape in his diagnosis of Cichlaurus. His reference to Cichla may have been only Schneider's (1801) drawing of Cichla ocellaris showing a rounded caudal fin, whereas C. ocellaris typically has a truncate or slightly emarginate caudal fin.

Geographical distribution

Species of the genus have been recorded from a wide area including most of the Amazon, Orinoco, Paraguay, Paraná, Uruguai and São Francisco basins, and also Trinidad, Guianan rivers, the NE coast of Brazil, Rio Grande do Sul and Uruguay.

References

[INTERNATIONAL COMMISSION ON ZOOLOGICAL NOMENCLATURE]. 2000. Opinion 1954. Labrus Linnaeus, 1758, Cichlasoma Swainson, 1839 and Polycentrus Müller & Troschel, 1849 (Osteichthyes, Perciformes): conserved by the designation of Labrus mixtus Linnaeus, 1758 as the type species of Labrus and L. bimaculatus Linnaeus, 1758 as the type species of Cichlasoma; and Polycentrus schomburgkii Müller & Troschel, 1849: specific name given precedence over L. punctatus Linnaeus, 1758. Bulletin of Zoological Nomenclature, 57: 131-136.
KULLANDER, S.O. 1983. Revision of the South American cichlid genus Cichlasoma. Swedish Museum of Natural History, Stockholm.
SWAINSON, W. 1839. The natural history of fishes, amphibians & reptiles, or monocardian animals, vol. II Lardner's Cabinet Cyclopaedia, Longman, Orme, Brown, Green & Longmans, London, 452 pp. Relevant pages 173(146kb), 230 (166kb), 231 (168kb)