Order Atheriniformes ( Atheriniformes )
Family Melanotaeniidae ( Melanotaeniidae )
To be continued…
Genus Melanotaenia — Melanotaenia.
— Mayland’s Rainbowfish — Melanotaenia maylandi [Allen, 1983]. (Eng. – Mayland’s Rainbowfish). Western New Guinea. 9 cm. Adult males are olive-green with a brownish back and silvery-white lower half. The upper back and sides often reflect bluish or purple hues, accompanied by a series of narrow orange lines on the sides between each scale row. A faint dark blue stripe extends from the gill cover to the middle of the caudal fin base, often interrupted by large spots. Fins are colorless with a grayish to blue tinge, except for the yellow anal fin. pH 6.0-8.5; T 22-28°C.
— Misool Rainbowfish — Melanotaenia misoolensis [Allen, 1982]. (Eng. – Misool Rainbowfish). Papua New Guinea. 6 cm. Body of adult males with a bluish or golden bronze tint on the upper head and back, often with a golden sheen in front, and silvery-white on the lower half. The upper sides feature 6-7 narrow pale orange lines between the scales.
A faint, spotty dark blue stripe extends from the gill cover to the middle of the caudal fin base. A narrow yellowish stripe is located directly beneath the dark spots, running from the pectoral fin to the level of the middle anal rays. Orange spots appear on the upper part of the gill cover. Fins are colorless with a yellowish tint. Peaceful in temperament and can be kept in a community aquarium with other non-aggressive species of approximately the same size. pH 6.0-8.5; T 22-28°C.
— Mubi Rainbowfish — Melanotaenia mubiensis [Allen, 1996]. (Eng. – Mubi Rainbowfish). Papua New Guinea, Mubi River basin. 9 cm. Iris is golden. Body greenish to bluish in the upper half of the head and back, often with a golden gloss, lower part whitish. A dark blue stripe runs along the side from the posterior edge of the eye to the caudal fin base, wider on the caudal peduncle; beneath it is a narrow yellowish stripe running from the pectoral fins to the middle of the anal fin. The upper half of the body features 6-7 pale orange stripes between scale rows. An orange spot is present on the upper part of the gill cover.
The first dorsal fin is pale green or bluish. The second dorsal and anal fins are blackish, bluish at the base. The caudal fin is bluish, translucent, with narrow dark bands on the upper and lower margins. Pelvic fins are translucent with a dark leading edge, pectoral fins mostly translucent. Males are brighter than females, with a deeper body. Dorsal and anal fins in males are colored and have a dark border, whereas in females they are transparent or bluish. Females are less intensely colored.
— Black Banded Rainbowfish — Melanotaenia nigrans [Richardson, 1843]. Synonym: Melanotaenia nigra, Atherina nigrans. (Eng. – Black Banded Rainbowfish, Dark Australian Rainbowfish). Northern and Western Australia, Cape York Peninsula. It should be noted that for a long time M. splendida australis or M. fluviatilis were kept in aquariums under the name M. nigrans. 7-10 cm. This species has a slimmer body than most other rainbowfishes. Coloration is modest, lacking spots and dashes. The upper half of the silver-reflecting body is greenish-olive, the lower is silvery-white. Large scales bordered with red create a reticulated pattern.
The fish has only a single wide horizontal black stripe running from the upper lip to the base of the caudal fin. The male has a bright carmine-red spot on the gill cover; a golden line of large, clearly distinct scales extends along the middle of the body, bordered in the caudal peduncle area by two rows of small scarlet dots, with identical distinct scarlet dots present along the upper half of the body between scale rows.
Red-orange dashes are scattered across the grayish fin membranes, and blackish dots appear on the caudal fin. The male is larger, the first rays of the anal fin are strongly elongated and white, and the caudal fin is blood-red. In the female, the caudal fin is reddish. The dorsal and anal fins in males are colored with a dark border, while in females they are transparent without a pronounced dark border. The red color of the caudal fin is more pronounced in males and not always noticeable in females.
Many color variations are found in different geographical localities. Specimens from Kimberley exhibit several central black lines and red fins. Some populations display blue body and fin coloration. Geographical color variations: — Melanotaenia nigrans “Anniversary Creek”; — Melanotaenia nigrans “Adelaide River”; — Melanotaenia nigrans “Dominic Creek”; — Melanotaenia nigrans “Robin Falls”; — Melanotaenia nigrans “Scotts Creek”;
These are schooling fish, typically keeping to the middle and upper water layers, and are less active compared to other schooling fish. They fall ill when kept in very soft and acidic water. For successful aquarium maintenance, it is advisable to add 1-2 teaspoons of marine salt to the water. They take food poorly from the bottom. pH 5.5-7.0; dH 8-15°; T 20-26°C.
— Oktedi Rainbowfish — Melanotaenia oktediensis [Allen & Cross, 1980]. (Eng. – Oktedi Rainbowfish). New Guinea, in tributaries of the Ok Tedi River. 10 cm. The body is copper-brown above the lateral line, while the lower half is white or pale lilac. Prefers heavily oxygenated water. pH 7.3-8.7; T 20-24°C.
Melanotaenia praecox, papuae, parva, parkinsoni, pierucciae.
Melanotaenia lacustris, lakamora, maccullochi, monticola. 
