RNDr. Roman Slaboch

Translate: Eli Slabochova

One of the most bizarre and also the most beautiful livebearers is Halfbeak harlequin (Nomorhamphus liemi liemi /Vogt, 1978/). It is one of the few “breed able” species of the Hemiramphidae tribe, which are over 110 in 14 species. They live entirely in southeastern Asia and Indonesia. N. l. liemi (mentioned above) lives on Sulawesi.

Females are approximately twice as big as males and they occupy mostly the vegetation under the surface. Males are sometimes by the bottom, which they leave because of females and food. The food are ideally insects and everything alive moving on the surface or close to the surface. Other food they take only tentatively and with bigger time interval, so that feed the shoal of 10 adult with scratched meat is work at least for one hour. They like to eat living bloody worms (like most fish does) but they eat them only from the surface or coming down at the moment. Feeding on the bottom is unusual. I turned out well to let bloody worms dry-up to stay longer on the surface. Unfortunately, I didn’t succeed in this with meat because dried-up edges become hard and halfbeak reject them. They seldom pick food felt on the bottom and if they do it, they are adult and males. I often saw that they even take tiny snails (less than 5 mm). The problems of feeding are also the main problems of breeding. I there is no living food available (insects on the surface or insect grubs floating in water), it takes a long time to feed them and hardly anybody has the patience to take care of it, then the fish suffer from the underfeeding and breed with difficulty.

Number of the young is contentious – it depends on the information source. There are mostly featured limits of 30 pieces, but I have read even about the litters of over 100 young. If we consider the size of the young (about 2–2,5 cm), so it is surely extreme. Females that I have bred littered less than 20 young. The young are not very movable in first days and it takes about one week till they start to eat properly. Then is their breed easy. (In the first, under mentioned information source there is an advice to breed them with the young of more aggressive and more movable Dermogenys pusillus, which will "teach" them to diet more quickly. I trust it, because if I have placed them with the litter of other livebearers, they grew distinctively quicker.)

Regarding to their size, they need bigger and rather lower well grown aquarium with the clear part of the surface. If you were lucky to set this aquarium on the place well-lightened by the sun, males can show amazing iridescence, which you could never seen by the other livebearer and actually by hardly any freshwater fish.

For male imposing, there is characteristic the flapping motion of the butterfly flight; and their caruncle ("neb") on the mandible certainly affects their sexual fruitfulness. But there is unexpected cause and consequence: I got off, that the stateliest males have had always neb before they were physically ripe. Males, which never have the caruncle, stay tiny and females refuse them. Males with the neb (even though they are tiny) get credit and than easier access to food, so they amplify quickly and others don’t have any opportunity.

This implies that males don’t have neb because they are strong, but they are strong because they have neb.

Fish aren’t exacting on the water temperature, 25 °C is adequate. If you afford them pH 7 to 8, they will be resistant to diseases. The only things that I have ever had to get off were Diplozoon and Dactylogyrus.

Except the problems with feeding (especially the females), there is another handicap –long– lasting maturation of males. It takes about 2-3 years until they will reach for the rich color and grow up to the best bizarre monstrosity. But you needn’t worry about it. Regarding to their relative longevity (5–6 years), you will enjoy them well enough.

Resources:

Dokoupil, N., Zemánek, L., (1988): O polozobánkách rodu Nomorhamphus, Akvárium Terárium 3/str.3, Panorama, Praha.
Kempkes, M., Schäfer, F., (1998): Alle Lebendgebärenden der Welt. Mörfelden-Walldorf, A.C.S. (Aqualog), 352 ss.
Májsky, J., (1995): Polozobánka ze Sulawesi, Akvárium terárium 5/str.13, Panorama, Praha.
Wischnath, L.,(1993): Atlas of Livebearers of The World, T.F.H. Publications, Inc.; USA, 336 ss.