NEOBROTICA AND RELATED GENERA — BLAKE 351 



Potamohrotica, new genus 



Head with a very short carina, a mere knob vanishing below the 

 antennal sockets; antennae fiUform, with the third, fourth, and fifth 

 joints long and subequal, remaining joints somewhat shorter, but 

 not as short as in Cerotoma; prothorax rather short and broad with 

 a transverse sulcus. Elytra coarsely and densely punctate, the punc- 

 tures tending to be striate; traces of costae. Anterior coxal cavities 

 closed, claws appendiculate. 



Type species: Potamobrotica trifasciata, new species. 



Locality: All three species of this genus are from the Amazon 

 part of Brazil, one extending into Venezuela. 



Remarks: Except for the head with the very short carina visible 

 only between the antennal sockets, and the closed anterior coxal 

 cavities, this genus is similar to Neobrotica. However, the prothorax 

 is a Uttle shorter and broader. The genus differs from Cerotoma in 

 not having the third antennal joint longer than the fourth. The 

 antennae in this respect resemble most species of Neobrotica. No 

 male of any of the three species has been examined, so there is the 

 remote possibility that there are sexual differences in the face and 

 antennae. 



The name Potamobrotica is derived from the Greek vorafios, meaning 

 "river," and Bpcotlkch, meaning "voracious." 



Potamobrotica trifasciata, new species 



Figure 102 



Between 7 and 8 mm. in length, oblong oval, feebly shining, 

 alutaceous, the elytra densely and coarsely punctate and feebly 

 costate, pale reddish or yellowish with deep brown markings on the 

 head and three deep brown fasciae on the elytra often interrupted at 

 the suture and sometimes connected along the lateral side. 



Head with the interocular space almost half width of head, carina 

 short, only a little knob between the antennal sockets, below it the 

 front depressed and then swollen transversely over the labrum, frontal 

 tubercles distinctly marked and with a median depression above, 

 occiput well rounded, reddish brown, lower front pale yellowish brown. 

 Antennae pale brownish, the ninth joint pale yellow and two apical 

 joints deep brown. Prothorax almost rectangular with slightly ciu-ved 

 sides and a well marked transverse sulcus, alutaceous, very finely and 

 inconspicuously punctate, pale yellowish brown. Scutellum pale. 

 Elytra alutaceous, not shiny, densely and coarsely punctate, the punc- 

 tures tending to be striate, surface somewhat rugose with indistinct 

 traces of costae, yellowish brown with three deep chocolate colored 

 fasciae not reaching base, apex, suture or margin in one specimen, the 

 fasciae at base in three of the four specimens broken into two spots. 



