Luciosoma pellegrinii

Luciosoma: from the Latin lucius, meaning 'a fish (probably the pike)', and Ancient Greek σῶμα (sôma), meaning 'body', in reference to the elongate, pike-like body shape in members of this genus.

pellegrinii: presumably named in honour of French zoologist Jacques Pellegrin (1873-1944).

Endemic to Borneo, with its range extending northeastwards from the Kapuas River watershed in West Kalimantan (Kalimantan Barat) province, Indonesia, through East Kalimantan (Kalimantan Tengah) to the Malaysian state of Sabah. The majority of records are from the Mahakam and Segama river systems.

Type locality is 'Bo River, Borneo', which appears to correspond to a location in the upper Kapuas basin.

A riverine species which apparently displays a preference for deeper habitats with slow-moving water.

The major proportion of this species' natural diet is composed of terrestrial insects which are captured at the water surface, although presumably it also feeds on aquatic invertebrates, fish fry and suchlike.

Luciosoma species are only suitable for the largest private aquaria, although subadults of L. setigerum, L. bleekeri, and an unidentified fish with a distinctive colour pattern (see below) are traded on a regular basis. They are mostly marketed as 'apollo shark', 'shark minnow', or similar, and often labelled with incorrect scientific names.

Luciosoma spilopleura is used very commonly, for example, but that species may never have been collected for aquaria. Similarly, L. pellegrinii is scarcely known in the aquarium trade since it is native to an area where very few commercial collections take place, but its name is misapplied on a regular basis.

The five species which currently comprise Luciosoma can be distinguished by elements of colour pattern. Popta described that of L. pellegrinii as follows: body colour olive dorsally, with dark-edged scales, yellow ventrally; a lateral series of dark spots on the flank forming a midlateral band which extends onto the opercle but not the head; 4-8 blackish-brown, distinctly-separate spots on the lateral line; fins yellow; dorsal and anal fins with a blackish-brown band; anterior half of some pectoral-fin rays blackish-brown; first two-thirds of caudal-fin rays blackish-brown, especially visible on the four short central rays.

In addition, the dark lateral stripe does not continue into the upper caudal-fin lobe as in L. bleekeri, L. setigerum, and L. trinema, while the caudal-fin also lacks a marginal stripe in the upper lobe unlike in L. spilopleura, L. setigerum, and L. trinema. L. pellegrini also appears to develop longer filamentous extensions on the anterior pelvic-fin rays than any other member of the genus.

There is a fish of unknown geographical origin which matches the majority of diagnostic features for L. setigerum with the exception that the dark lateral stripe is absent in the anterior portion of the body and is not composed of interconnected spots. It is relatively common in the aquarium trade and referred to here on SF as L. cf. setigerum until a confirmed identity is established. Images are available on the L. setigerum profile page.