Synopsis of Ophthalmotilapia Pellegrin, 1904

Type species: Ophthalmotilapia boops (Boulenger, 1901)

Distinctive characters:

• Body relatively deep, depth being 29.8 – 40.3 % of standardlength. Head with a rounded profile.
• Dorsal XII-XVI, 13-15. Anal III, 7-10. Ventral fins in mature males prolonged with spatulae, nearly reaching to the caudal fin. The soft rays of the unpaired fins are prolonged and may reach beyond the origin of the caudal fin. The outer rays of the caudal fin are long and filamentous.
• 3-5 oral teeth rows, being either uniscuspid or tricuspid.
• 15-21 gill rakers on ceratobranchial.
• Lower pharyngeal bone triangular, densly covered with mainly bicuspid teeth
• 36-40 scales along the longitudinal line.
• Two lateral lines.

Species currently included:

Ophthalmotilapia boops (Boulenger, 1901)

Type locality:

Msambu, Tanzania.

Taxonomic history:

• Ophthalmotilapia boops (Boulenger, 1901) - by Pellegrin 1904
• Tilapia boops Boulenger, 1901

Synonyms:

None.

Link to Ophthalmotilapia boops in the CRC Catalogue.

Ophthalmotilapia heterodonta (Poll & Matthes, 1962)

Type locality:

Mboko Island, D.R. Congo (former Zaire)

Taxonomic history:

• Ophthalmotilapia heterodonta (Poll & Matthes, 1962) - by Konings 1988
• Ophthalmotilapia heterodontus (Poll & Matthes, 1962) - by Poll 1986
• Ophthalmotilapia ventralis heterodontus (Poll & Matthes, 1962) – by Liem 1981
• Ophthalmochromis ventralis heterodontus Poll & Matthes, 1962

Synonyms:

None.

Link to Ophthalmotilapia heterodonta in the CRC Catalogue.

Ophthalmotilapia nasuta (Poll & Matthes, 1962)

Type locality:

Kalungwe, D.R. Congo (former Zaire).

Taxonomic history:

• Ophthalmotilapia nasuta (Poll & Matthes, 1962) - by Takamura 1984
• Ophthalmotilapia nasutus (Poll & Matthes, 1962)) - by Liem 1981
• Ophthalmochromis nasutus Poll & Matthes, 1962

Synonyms:

None

Link to Ophthalmotilapia nasuta in the CRC Catalogue.

Ophthalmotilapia ventralis (Boulenger, 1898)

Type locality:

Kinyamkolo and Mbity Rocks, Zambia.

Taxonomic history:

• Ophthalmotilapia ventralis (Boulenger, 1898) - by Greenwood 1978
• Ophthalmochromis ventralis ventralis (Boulenger, 1898) - by Poll & Matthes 1962
• Ophthalmochromis ventralis (Boulenger, 1898) - by Poll 1956/li>
• Ophthalmotilapia ventralis (Boulenger, 1898) - by Regan 1920
• Paratilapia ventralis Boulenger, 1898

Synonyms:

None

Link to Ophthalmotilapia ventralis in the CRC Catalogue.

Remarks on taxonomic status:

The genus Ophthalmotilapia was originally described by Pellegrin in 1904, and several authors has since re-diagnosed the genera and the varying number of included species, e.g. Regan (1920), Poll & Matthes (1962), Greenwood (1983) and Poll (1986). Recently Hanssens et al. (1999) did a morphometric analysis of Ophthalmotilapia, and they found several inconsistencies in the hitherto published material on the genus, when compared with the type-series, and a new diagnosis of the genus and its species was designated (listed above).

Hanssens et al.’s analysis showed the existence of a population at Mtoto, D.R. Congo, that could not be designated to either O. ventralis or O. heterodonta, and interestingly this population differ clearly in coloration from both the northern O. heterodonta and southern O. ventralis populations. The taxonomic status of the Mtoto population is still uncertain.

The molecular analysis of the tribe Ectodini by Koblmüller et al. (2004) showed that Ophthalmotilapia form a subclade within the Ophthalmotilapia-clade, together with the genera Cardiopharynx and Cyathopharynx. The analysis could not support the monophyly of the genus Ophthalmotilapia, as O. heterodonta and O. ventralis formed a cluster together with Cyathopharynx furcifer (could actually be C. foae, a taxa not considered valid by all authors, neither in the publication by Koblmüller et al.), whereas Ophthalmotilapia nasuta and O. boops formed a sister species pair. Koblmüller et al. therefore suggest a revision of the genus Ophthalmotilapia.