^^ . 208 



madeiremis; some specimens exhibit an overall darker background coloration, but 

 still have a strongly spotted pigmentation pattern on the sides and body. Heavily 

 pigmented specimens have a crescentic band of melanophores on the anterior half 

 of the chin between the dentaries. Paired fins are generally unpigmented except for 

 scattered brown flecks on top of the pectoral spine and/or the first interradial 

 membrane. Dorsal, adipose, and anal fins are usually unpigmented, but occasionally 

 there are diffuse brown specks at the base and along the distal margin of the anal 

 and the anterior margin of the dorsal. 



' h'. ' 



Distribution 



This species is confined to the Amazon River basin, primarily from the 

 headwater drainages in Peru and Bolivia and the upper half of the Amazon (Rio 

 Solimoes) proper (Fig. 39). The scattered localities from which specimens are 

 available presumably reflects a lack of intense collecting efforts rather than locally 

 disjunct populations. 



Ecology 



Nothing published. This species, likey4. atronasus, matures at a very small 

 size; nuptial males were identified at sizes of about 55-60 mm SL. 



Etymology 



From the Latin brevis, meaning short, in reference to the blunt snout of this 

 species. 



