Order Characiformes
Family Anostomidae (Headstanders)
Representatives of the family inhabit standing and slow-flowing waters of Central and South America, including the Caribbean islands. All members of the family possess an adipose fin characteristic of the characiform suborder. The mouth of these fishes is small, with protruding, thick, rough lips, which, together with small teeth, allow them to scrape off various algae and growths, often damaging plants. They feed mainly on plant-based foods. Some species possess additional respiratory organs.
Usually, they stay in small groups in bottom areas, among dense thickets of vertically growing aquatic plants, camouflaging themselves perfectly among them. A characteristic and very interesting feature of the most famous fish of this family is their head-down body position, adopting a horizontal position only during flight, which makes the presence of fish of this group in the aquarium very desirable, especially in combination with vertically standing Nannostomus. The coloration of many fishes in the family is also very attractive. Large fish are poorly suited for aquarium maintenance.
Abramites have a slightly higher body than other genera of the family; broad, brown, transverse stripes are visible against a brown or golden body background, and the fins are muddy yellow. Leporinus have a more elongated, slender body. They are not very popular in aquarium hobby because they reach their final length too quickly and turn out to be too large for home aquariums. Longitudinal and transverse stripes and spots create the characteristic coloration of various species. Their transverse stripes always run through the eye.
Aquariums should be large, tall, with a soft substrate, hiding places in the form of snags, crevices between large stones, planted with tall, vertically growing plants with tough leaves. The water should be soft, peat-filtered, and hardness above 10°dH is unacceptable. Partial water changes will contribute to the well-being of the fish. Keep anostomids either as single specimens in a community aquarium or in a group of 7 individuals or more.
For reasons known only to themselves, they become very aggressive if kept in small groups. They are poorly compatible with members of their own family; adult fish are usually territorial and, in a limited volume of water, aggressive towards each other and other fish. Only young fish can be kept. Males are smaller, brighter, and slimmer than females. They reach sexual maturity at 2-3 years. dH up to 15°; pH 6.0-7.5; T 22-28°C.
Genus Abramites
— Marbled Headstander — Abramites hypselonotus [Gunther, 1868]. Synonyms: Abramites microcephalus, ternetzi, Leporinus hypselonotus, nigripinnis. (Eng: Abramite, High Backed Headstander, Marbled Headstander). Colombia, Peru, Bolivia, Brazil, Paraguay, Ecuador, and Venezuela, Amazon, Orinoco, Paraná, and Paraguay rivers. 12 cm. The fishes have an elongated fusiform body.
Beige-golden or light brown in color with 7-9 undulating coffee, dark gray, or almost black stripes across the body, extending onto the dorsal and anal fins. The upper part of the head and the adipose fin are yellowish. A horizontal stripe runs through the large eyes. The dorsal and ventral fins have dark stripes, while the rest of the fins are transparent. Females are fuller and paler colored than males. Known subspecies: — A. hypselonotus ternetzi. From the Paraguay River. Characterized by a more anteriorly positioned dorsal fin and a greater width of the caudal fin base.
An aquarium with a volume of 150 liters or more is required, with various hiding places in the form of stones, grottoes, and snags at the bottom. They prefer dim lighting, staying mainly in the middle and lower water layers. They swim head-down at a 40° angle near the bottom. The fish are timid and can jump out of the water. Young individuals are schooling, peaceful, and suitable for a community aquarium. As they mature, signs of aggression appear between the fish, and they become pugnacious. Adult fish larger than 10 cm are aggressive both to their own kind and to other species.
The fish have very well-developed jaws that allow them to defend themselves excellently against other fish, as well as attack them. For this reason, adult fish should preferably be kept in a species aquarium in a large group. They destroy vegetation; only tough-leaved plants can be grown, as the fish nibble on algae and young tender shoots. It is advisable to plant artificial plants close together to create dense thickets. Enhanced water filtration and aeration, as well as weekly water changes, are required.
Plant-based food with the addition of small live food. They eat frozen peas, lettuce leaves, young shoots of vegetable and grain crops. If plant food is insufficient, the fish will quickly deal with all live plants in the aquarium, if any. They mature at 1.5-2 years of age, reaching a length of 7 cm. Breeding fish in aquarium conditions is quite difficult. Lifespan is about 10 years. pH 6.0-7.5; dH 5-18°; T 23-27°C.
— Four-striped Headstander — Abramites eques [Steindachner, 1878]. Synonym: Leporinus eques. Colombia, Amazon and Orinoco river basins. 12 cm. Body elongated and spindle-shaped, head sharp, mouth small, caudal fin particularly well developed. Olive-beige coloration with 4-6 wide brown transverse stripes, some half-length and extending onto the fins. The caudal fin is dark at the base but otherwise colorless. The fins are almost completely transparent with faint dark brown patterns. Males are brighter and slimmer.
May be aggressive towards individuals of their own species; keep with fish of similar size. Rocks and roots should be added to provide hiding places for the fish. Plants will be eaten. Strong filtration using peat is required. May jump out. Plant-based food with the addition of small live food. Soft, acidic water. Prefers plant food, spinach, lettuce, supplemented with dry food and tubifex. Lifespan is 5 years. pH 6.5-7.0; dH 4-16°; T 22-26°C.
Genus Laemolyta
— Banded Headstander — Laemolyta taeniata [Kner, 1858]. Synonyms: Schizodon, Anostomus taeniatus. Middle Amazon. 12-20 cm. Body coloration can change depending on keeping conditions – brown, yellow, or silver. Mostly silvery-yellow, with reticulated scales on the back and a dark brown stripe along the body, extending from the mouth to the tail. Belly is beige to whitish. The tip of the snout is red, and in adult fish, the eyes also become reddish. Fins are transparent. A brown lattice pattern on the body is a sign that the fish is frightened or sleeping.
Non-aggressive schooling fish. Should be kept separately or in groups of six or more. If kept in smaller groups, the fish will fight. Should not be kept with small fish; suitable for community tanks with cichlids or similarly sized fish. Swims head down in the middle and lower water layers. Use a powerful filter to create a current. Fish are sensitive to water hardness; water should be soft, pH 5.0-6.5. It is desirable to peat-filter the water. Live and frozen foods, plant flakes, and pellets are used for feeding. dH 0-8°; T 24-28°C.
Genus Pseudanos
— Threespot Headstander — Pseudanos trimaculatus [Kner, 1858]. Synonyms: Schizodon, Anostomus trimaculatus. (Eng: Threespot Headstander). Peru, Brazil, Guyana, northern Amazon basin. 12-15 cm. Spindle-shaped body with a long caudal peduncle. Pointed head with a superior mouth; sometimes they feed from the bottom while lying on their backs. General body tone is silvery-brown, darker on the back.
A series of thin vertical stripes can also be seen on the rear part. Three spots on the flanks: the largest one below the dorsal fin, and another at the base of the caudal fin. The tip of the mouth is orange-red. Fins have a reddish color, more or less intense depending on sex and condition of the fish. Males grow slightly smaller than females and are more colorful. Juveniles are brownish with faint dark stripes on the back.
The body of these fishes is inclined forward both while eating and at rest. A schooling fish, but the schooling instinct manifests only when a few individuals are kept. Generally very compatible. Aggressive towards their own species when kept in small numbers. Hiding places among snags, roots, and tough-leaved plants, along with floating plants on the surface, are highly desirable. The lid should fit well because they are prone to jumping.
Soft young shoots are far from safe from them; they will be eaten, and even tough species will be nibbled. Providing a varied plant diet can substantially moderate their love for vegetation. They like to scrape algae from the undersides of leaves. Water flow should be fairly strong. Mostly herbivorous fish, they consume live and frozen food in small quantities. They eagerly peck at sinking tablets. pH 6.0-7.0; dH up to 18°; T 23-28°C.
Genus Synaptolaemus
— Synaptolaemus cingulatus [Myers & Fernandez & Yepez, 1950]. Upper reaches of the Orinoco and Xingu rivers. 12 cm. Brownish-black with 8-9 crimson ribbons across the body. Fins are bluish; the bases of the dorsal, adipose, anal, and ventral fins are dark. Sociable, schooling fish; a large aquarium with dense vegetation is required. Swims head down. The species prefers meaty foods, crustaceans, and insect larvae. dH 2-10°; pH 5.8-6.8; T 23-28°C.
Anostomus anostomus, ternetzi.
Phenacogrammus altus, interruptus, urotaenia. 
