Comprehensive DescriptionRead full entry
Type species: Acestra acus Kner, 1853 ZBK .
Holotype : NMW 47795 , Venezuela , Caracas .
The genus Farlowella ZBK is broadly distributed in Amazon, Orinoco, Paraná , and coastal rivers of the Guyana Shield. Curiously, it seems to be absent from the Pacific slope of the Andes and from the coastal rivers of the Brazilian shield. Farlowella ZBK has a very unique body shape that resembles of a thin stick of wood. The body is slender and elongate, often with a pronounced rostrum and a brownish color with two lateral dark stripes beginning at the tip of the rostrum, passing over the eyes and ending at the tail, which are periodically interrupted on the caudal peduncle. Species inhabit areas of gently flowing water in submerged dead leaves and sticks, among which it blends remarkably (pers. obs.). Some specimens can sometimes be found in swift current over rocks and submerged wood. These species appear scarce (Le Bail et al. 2000, Evers & Seidel 2005) but their mimicry can explain in part this apparent scarcity (Le Bail et al. 2000). Sexual dimorphism includes hypertrophied odontodes along the sides of the rostrum or the head in species with a short rostrum. These species are open water brooders (pers. obs.). The eggs are laid on open vertical surfaces such as submerged vegetation or rocks, in a single layer and are guarded by the male. Morphological (Rapp Py-Daniel 1997) and molecular (Montoya-Burgos et al. 1998) phylogenetic studies have placed Farlowella ZBK as sister to Sturisoma . This relationship is supported by their sexual dimorphism and reproduction strategy, which are identical in all respects. For these reasons, the tribe Farlowellini described by Isbrücker (1979) herein is considered a synonym of Harttiini . The character used to define Farlowellini (i. e. the relative position of the dorsal and anal fins), is subjective and could be interpreted as a generic feature following the example of European cyprinids like Scardinius erythrophthalmus and Rutilus rutilus which are also distinguished by this criterion. A revision and a key to twenty five valid species of Farlowella ZBK were made available by Retzer & Page (1997), and an additional species from the Rio Beni drainage in Bolivia has been described recently by Retzer (2006).