Volume 3, Issue 2 – Semptember 1998
Uwe Romer and Frank Warzel: Apistogramma arua sp. n. (Teleostei: perciformes: Cichlidae), a new species of dwarf cichlid from the Rio Arapiuns system, Para State, Brazil, pp. 45-44
Volume 3, Issue 2 – September 1998
Richard Winterbottom: A new species of the genus Trimma (Percomorpha; Gobiidae) from Helen Reef, South-West Islands of Palau, pp. 109-116
Apistogramma arua sp. n. is described on the basis of four specimens collected in a small igarapé near Arua in the lower course of the Rio Arua. This relatively small species (males up to 45 mm SL) may be related to the species of the A. cacatuoides complex sensu stricto as well as to the A. trifasciata-group, but at the time has to be placed incertae sedis within the genus. A. arua sp. n. is characterised by a wedge-shaped spot on the abdominal flank beneath the lateral band, which sometimes, depending on mood, is modified to a line or band between the gill cover and the frontal base of the anal fin, or to three indistinct abdominal bands formed by three rows of half-moon-shaped spots. Males additionally exhibit a forked caudal fin and extended membranes to the first 5-7 dorsal fin lappets.