River
Demerara
14 profiles across 7 families name the Demerara as a locality.
- Species
- 14
- Families
- 7
- Photographed
- 14 of 14
- Difficulty rated
- 14 of 14
Basin
Shares fishes withspecies recorded from both
Runs through

Anostomus anostomusStriped Headstander
Anostomidae · Linnaeus, 1758
A biotope-style set-up could consist of a sandy substrate, piles of smooth rocks and driftwood roots and branches, some of which should penetrate the water surface. Aquatic vegetation can be included if you wish but is likely to be eaten.

Apistogramma steindachneriSteindachner's Apisto
Cichlidae · Regan, 1908
This species is assigned the code A138 under the DATZ system, with the Venezuelan variant referred to as A139 for easy reference. The genus Apistogramma is among the most speciose of South American cichlid genera with around 70 species valid at present but many more awaiting description. In addition many species exist in two or more geographical colour forms which may or may not turn out to be distinct in the future. Hobbyists tend to label these with collection dat...

Brachychalcinus orbicularisDiscus Tetra
Characidae · Valenciennes, 1850
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...

Carnegiella strigataMarbled Hatchetfish
Gasteropelecidae · Günther, 1864
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...

Chilodus punctatusSpotted Headstander
Chilodontidae · Müller & Troschel, 1844
Omnivorous and will accept most foods offered, with the stomach contents of wild specimens varying on a seasonal basis but mostly comprising insects and insect larvae (orders Trichoptera, Hemiptera, Homoptera) plus some terrestrial fruits and even scales of other fishes (Sánchez et al., 2003). In the aquarium offer live Daphnia, Artemia, Moina, bloodowrm, etc., vegetable matter in the form of blanched spinach, lettuce, cucumber, fruit, algae wafers, etc., and good quality, sinking dried foods.

Cleithracara maroniiKeyhole Cichlid
Cichlidae · Steindachner, 1881
This species can be told apart from relatives by the characteristic 'keyhole' shaped marking on each side of the body. It's one of few fishes in which the current generic name is derived from the common name popularised in the aquarium hobby with 'Cleithracara' a combination of the Greek kleithron, meaning lock, and, acará, the Guaraní word for cichlids.

Copella arnoldiSplash Tetra
Lebiasinidae · Regan, 1912
This species is also known as the 'spraying', 'splashing' or 'jumping' tetra and these names are also sometimes applied to its congeners although none of them exhibit a comparable spawning strategy, simply depositing their eggs among vegetation at or around the water surface.

Crenuchus spilurusSailfin Characin
Crenuchidae · Günther, 1863
This species is currently the only described member of its genus although colour pattern and morphology vary considerably across its range. You may see reference to this species being the only fish species to possess infra-red vision, but other species also possess this ability and we suspect that infra-red plays an important role in the reproductive cycle of many fishes.

Geophagus brachybranchus
Cichlidae · Kullander & Nijssen, 1989
This species is generally rare in the aquarium hobby though oddly appears to be one of the commoner species in Australia where it's often referred to by the vernacular name 'black-throated eartheater'. It's a member of the nominal G. surinamensis 'group' of closely-related species within the genus and can be identified by a combination of characters including: presence of dark preopercular markings; no vertical bars on the flanks even when stressed/preserved; base of filaments on the first gill arch mostly covered by a flap of skin; exposed part of bra...

Leporinus fasciatusBanded Leporinus
Anostomidae · Bloch, 1794
This species is also referred to as 'black-anded leporinus', 'striped leporinus' and 'eight-banded leporinus'. Young specimens are often traded for aquaria without warning as to their potential size and requirements, and as a result it's fairly ubiquitous in public aquarium displays.

Nannostomus beckfordiGolden Pencilfish
Lebiasinidae · Günther, 1872
This is the type species of the genus, fairly ubiquitous in the aquarium trade, and represents an excellent choice for the newcomer to fishkeeping since it's less demanding than most congeners. It's sometimes referred to as 'Beckford's pencil fish' or 'brown pencilfish'. Don't worry if your fish look different when you switch on the aquarium lights after dark or in the morning as like most Nannostomus species it assumes a cryptic, vertically-barred colour pattern at ni...

Nannostomus harrisoniBlackstripe Pencilfish
Lebiasinidae · Eigenmann, 1909
This species is quite rare in the aquarium hobby and is not often available in numbers, more often being exported as bycatch among shipments of the congener N. eques. Following Weitzman and Cobb (1975) it can be diagnosed by the following combin...

Nannostomus marginatusDwarf Pencilfish
Lebiasinidae · Eigenmann, 1909
There also exist a number of minor differences in colour pattern between populations. For example some Peruvian forms have yellow pigmentation on the body and fins, and those from Guyana and Suriname possess a short red stripe on vertical scale rows 6-9, above the central dark stripe on the body. Rio Negro forms have a similar red stripe but overlapping the central dark stripe and extending along most of the flank, while a form from Colombia has an elongate red stripe which is broken in two beneath the dorsal-fi...

Satanoperca leucostictaWhitespot Eartheater
Cichlidae · Müller & Troschel, 1849
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...