Synaptolaemus latofasciatus (STEINDACHNER, 1910)

SynonymsTop ↑

Leporinus latofasciatus Steindachner, 1910; Synaptolaemus cingulatus Myers & Fernández-Yépez, 1950

Etymology

latofasciatus: from the Latin latus, meaning ‘broad’, and fasciatus, meaning ‘banded’.

Classification

Order: Characiformes Family: Anostomidae

Distribution

Type locality is ‘Orinoco River, Venezuela’, but this species is widely-distributed throughout the upper Orinoco, Casiquiare Canal and middle-to-lower Amazon region in Venezuela and Brazil with records existing from the rios Negro, Madeira, Trombetas, Xingu and Tapajós.

There are certain differences in morphology, especially that of the snout, and colour pattern depending on locality.

Maximum Standard Length

100 – 110 mm.

Aquarium SizeTop ↑

An aquarium with base dimensions of 120 ∗ 45 cm or equivalent should be the smallest considered.

Water Conditions

Temperature: 20 – 28 °C

pH: 5.0 – 7.5

Hardness: 36 – 215 ppm

Diet

Likely to be a foraging omnivore browsing algae, invertebrates and organic detritus from submerged solid surfaces in nature.

Apparently it’s quite unfussy in the aquarium and will accept most things offered, although foods containing high levels of protein are best avoided.

NotesTop ↑

This species was described from a single specimen and included in the genus Leporinus until 2011 at which point the holotype was examined and recognised as corresponding to the fish described as Synaptolaemus cingulatus (Myers & Fernández-Yépez, 1950).

The latter was therefore concluded to be a synonym of L. latofasciatus with Synaptolaemus latofasciatus the currently-accepted name since the genus Synaptolaemus has been clearly diagnosed (Myers & Fernández-Yépez, 1950; Winterbottom, 1980) and was recovered as a monophyletic lineage, most closely-related to Gnathodolus and Sartor, in phylogentic analyses (Sidlauskas and and Vari, 2008).

In the latter study  Synaptolaemus was placed in a large polytomy alongside the genera Anostomoides, Anostomus, Gnathodolus, Laemolyta, Petulanos, Pseudanos, Rhytiodus, Sartor, and Schizodon plus a clade formed by most species of Leporinus and the genus Abramites.

Synaptolaemus can be told apart from other anostomids in that the symphyseal teeth of the lower jaw are around twice as long as they are broad (vs. subequal or 5 times as long as broad), and the gill membranes are broadly united with the isthmus.

In addition the lower jaw is about twice as long as it is broad and appears vertical when the mouth is fully-closed and the colour pattern comprises alternating transverse bands of orange or yellow and dark brown or black extending along the entire body and below the lateral line.

The family Anostomidae is distributed throughout much of tropical and subtropical South America from northwestern Colombia to central Argentina.

The majority of species are moderately-elongate and somewhat rounded in shape although there are some exceptions, e.g., the relatively deep-bodied Abramites.

Greater diversity is apparent in the range of oral morphology, however, and members exhibit a wide range of adaptations in dentition and jaw structure.

A number of anostomids tend to swim at an oblique ‘head-down’ angle which has given rise to them being referred to by the generalised vernacular term ‘headstanders’.

References

1. Britski, H. A., J. L. O. Birindelli and J. C. Garavello , 2011 - Zootaxa 3018: 59-65
   Synaptolaemus latofasciatus, a new combination for Leporinus latofasciatus Steindachner, 1910 and its junior synonym Synaptolaemus cingulatus Myers and Fernández-Yépez, 1950 (Characiformes: Anostomidae).
2. 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.
3. Sidlauskas, B. L. and G. M. dos Santos, 2005 - Copeai 2005(1): 109-123
   Pseudanos winterbottomi: a new anostomine species (Teleostei: Characiformes: Anostomidae) from Venezuela and Brazil, and comments on its phylogenetic relationships.
4. Sidlauskas, B. L. and R. P. Vari, 2008 - Zoological Journal of the Linnean Society 154(1): 70-210
   Phylogenetic relationships within the South American fish family Anostomidae (Teleostei, Ostariophysi, Characiformes).
5. Winterbottom, R., 1980 - Life Sciences Contributions Royal Ontario Museum No. 123: 1-112
   Systematics, osteology and the phylogenetic relationships of fishes of the Ostariophysan subfamily Anostominae (Characoidei, Anostominae).