Results for “genus”

This species is included in the Betta unimaculata complex of closely-related species within the genus, of which members share the following set of characters: body long and slender with depth at dorsal fin origin 18-25 % SL; head large and blunt with width 19-24 % SL; long maxilla and lower lip with distance from tip of lower jaw to posterior end of maxilla 27-54 % HL; caudal-fin rounded in shape, occasionally with elongated median rays; pelvic-fin short and filamentous; dorsal and anal fins relatively pointed.

Within the genus Boraras this species is most similar to B. naevus, though in the latter the red body colouration does not extend into the head. The two also differ in the following characters: anteriormost lateral blotch of comparable size in both sexes in B. maculatus vs. significantly larger in male than female B. naevus; 9-10 + 9 principal caudal-fin rays vs. 9 + 8; 26-29 lateral scales vs. 24-26; i.6.i. pelvic-fin rays vs. i.5.i.

Following Grant (2007) this species is included in the B. dario complex of closely-related species within the genus alongside B. striata. They're characterised by body patterning consisting of a base yellow to golden colour with 7-9 blue, green, grey or black body bars usually with thinner, lighter bars between. In some individuals the...

Boulengerella differs from Ctenolucia, the only other genus currently contained in the family Ctenolucidae, by a series of derived features including possession of 87-124 (vs. 45-50) lateral line scales, presence of a strongly (vs. weakly) developed fleshy appendage at the tip of the snout and absence (vs. presence) of fleshy flaps on the lower jaw. Within the order Characiformes the family Ctenoluciidae is also distinguished by a set o...

The genus Brachychalcinus currently contains four other species: B. copei (Steindachner 1882) from the rio Madeira and rio Solimões; B. nummus Böhlke 1958 from the Upper Amazon region in Colombia, Ecuador and Peru; B. parnaibae Reis 1989 from the rio Parnaíba basin, and B. retrospina Boulenger 1892 from the Rio Paraguay system. The group is often referred to collectively as 'silver dollar tetras' and tho...

This species is among the more frequently-traded members of the genus, although confusion regarding its identification and natural distribution is commonplace and it's often misidentified as B. nunus or B. xanthozonus. It can be diagnosed as follows: <30 lateral scales; one black band on head, three on body; first black band on body overlapping first dorsal fin to the extent that almost all fin, except a narrow margin, is black, and beginning opposite centre of opercle...

Type locality is '55 miles north of Singapore, freshwater ditches, Mawai District, Johore, Malaysia', and this species has been recorded throughout much of Peninsular Malaysia and southern Thailand. Records from Borneo and Singapore appear to be in error although it may have been extirpated from the latter but as with most members of the genus a degree of confusion surrounds its identity (see 'Notes').

In the Amazon region it is only specimens larger than around 160 cm and werighing in excess of 50 kg that are referred to as 'Piraíba' with the name 'filhote' normally applied to smaller individuals. Other vernacular names include 'Salton catfish', 'Kumakuma'; and 'tiger antenna catfish'; with members of the genus often referred to collectively as 'goliath catfishes'.

This species is sometimes confused with B. juruense, especially when juvenile, but can be told apart quite easily by it's more well-defined colour pattern, relatively slender body shape and longer barbels. It was described in the genus Meredontotus, but is currently included in Brachyplatystoma based on a pair of synapomorphies shared by memb...

Several Brachyrhamdia species have developed colour patterns that mimic syntopically-occurring Corydoras spp. throughout the life-cycle, and the remainder may mimic Otocinclus or smaller Corydoras spp. when juvenile. Among other catfishes they're closely-related to members of the genus Pimelodella, but differ in...

The Brycon genus is large, at present containing over 50 species. A number of these are very similar, a couple of which (B. rubricauda and B. orbignyanus) resemble B. cephalus quite closely. However this one is the most common in nature and is likely to be the species seen on sale most often. Commonly known as the matrinxã in Brazil, it has an interesting life cycle, migrating twice per year over large distances according to the season. The first movement occurs at the start of...

Rarely seen in the trade, as it is quite difficult to collect in nature. It retreats at great speed into deeper water at the first sign of threat. As with other members of its genus, it is a hunter, feeding mainly on smaller cichlids.

Bunocephalus is the largest genus within the Aspredinidae family and there are several undescribed species. B. coracoideus is the most common member seen in dealers' tanks. Its native name "Guitarrita" translates as "little guitar" and refers to the shape of the fish when viewed from above. Despite the regularity with which it is seen for sale, it isn't really a good catfish for the general community tank because it's a largely inactive, secretive species, ...

Butis spp. are largely nocturnal ambush predators with cryptic patterning to help them blend in with their surroundings. They can also lighten and darken their body colouration to an extent, have a habit of aligning themselves with solid surfaces whether horizontal, vertical, or inverted, and often swim in an upside-down position. The genus is usually included in the family Eleotridae of which members are often referred to...

Members of the genus Callochromis feed in a similar way to the South American "eartheaters" such as Geophagus species. They extract invertebrates and other items hidden in the substrate by taking in mouthfulls of sand and sifting it through the gills. The common term "sand sifters" is applied to these and other Tanganyikan species that inhabit a similar ecological niche, such as Enantiopus and Xenotilapia spp. Several geographical colour forms of this species exist. These ...

This species is relatively uncommon in the aquarium hobby but is available on occasion, sometimes mixed in among shipments of the congener C. salivator. These two can be told apart by the fact that C. salivator possesses a series of distinct dark bars on the head and body in both sexes, a colour pattern unique within the genus. It is also similar t...

C. strigata is an enduringly popular species in the aquarium hobby but is not bred on a commercial basis with all fish offered for sale collected in the wild. It can be told apart from other members of the genus by its larger adult size and dark, marbled colour pattern appearing as a series of dark and light stripes running diagonally across the body below the lateral line. This colour pattern is variable and popul...

A very cute little catfish, that unfortunately is rarely kept in ideal conditions. When it is maintained properly, it's a joy to watch as it feeds from close to the water surface, swimming frantically in the flow. It was reclassified, and placed in the genus Centromochlus in 1998.

The genus Centromochlus is diagnosable by members having the proximal anal-fin radials enlarged and fused to each other at the base, forming a single ossified structure. It's sometimes included in the putative subfa...

Endemic to the Ganges and Brahmaputra river basins and thus occurs in northern India, Nepal and Bangladesh. Type locality is 'the Yamuna River, and northern rivers of Behar and Bengal'. The distribution of the genus as a whole is interesting because these fish occupy the area that geographically separates Indian and Southeast Asia barbs and it has been theorised that they may represent an evolutionary 'link' species...