Indochinese Needlefish

About

The Indochinese needlefish (Xenentodon canciloides) is a surface-dwelling predator from the rivers and seasonally flooded lowlands of Thailand, the Mekong basin, and across to Indonesia. That long, slender beak packed with alternating canine and conical teeth makes it look dangerous, but it's actually a reasonably peaceable fish toward anything it can't fit in its mouth. It belongs to the family Belonidae, making it a true needlefish rather than a relative of the North American gars it superficially resembles. The vast majority of belonids are marine or estuarine, which makes this one of a small handful of genuinely freshwater representatives. Compared to its close relative Xenentodon cancila, this species has noticeably more slender jaws, a slightly smaller and more streamlined body, and a higher tooth count in the upper jaw. It's the rarer of the two in the hobby, with X. cancila turning up far more often at importers. Behaviorally, juveniles show a clear schooling tendency and adults remain non-aggressive toward conspecifics, so keeping four or more together is the right approach. It is, however, a poor competitor at feeding time, so tankmates need to be chosen with that in mind. Reproduction in aquaria has not been documented, though wild fish produce eggs with surface tendrils that anchor them to submerged objects.