158 NEOTROPICAL PSEL APHID AE 



BRYAXINA (Raffray, 1904) 



This is a genus of moderate size, closely related to Achillia, and restricted 

 to Brazil. The males have the second tarsomere of the anterior tarsi greatly 

 expanded laterally, flattened, with the ventral surface setose. The maxillary 

 palpi are four-segmented with the fourth segment irregularly pyriform or ir- 

 regularly pyramidal, the base being rounded, widening rapidly to basal third, 

 then lengthily narrowing to an acute apex, which bears a palpal cone, however, 

 this narrowing is accompanied by a distinct sinuation on the external face, so 

 that the external-apical outline is concave and the internal-apical outline is 

 convex. 



There are ten species known, and I have used Raffray's key (1904, pp. 

 262-263) for their separation since no new forms have been described. 



Each elytron with three basal foveae 2 



Each elytron with four basal foveae 4 



2. Basal discal carinae of first tergite one-third of the segmental 



length torticornis 



Basal discal carinae of first tergite one-fourth of the segmental length 3 



3. Antennae thick, with eighth segment strongly transverse, ninth less 



transverse than eighth, tenth nearly square, eleventh elongate-oval; 



head armed and excavated in the male sex armiceps 



Antennae thicker, with segment eight slightly and nine and ten 

 strongly transverse, eleven briefly obconical; head simple in the female 



sex (male unknown?) fraudatrix 



4. Antennal segments all longer than wide, or most of the segments longer 



than wide 5 



Antennal segments as wide as long (subequal), or fourth, eighth, 

 ninth, and tenth square at least 6 



5. Basal discal carinae of first tergite one-fourth of segmental length; 



antennal segments four and eight square lucida 



Basal discal carinae of first tergite one-third of segmental length; 

 antennal segments four and eight slightly longer than wide . . clavata 



6. Antennae with segments five, six, seven much longer than wide, and 



segments four, eight, nine, and ten square 7 



Antennae thick, with the segments not much longer than wide 8 



7. Basal discal carinae of first tergite one-third of segmental length 



dimidiata 



Basal discal carinae of first tergite one-fourth of segmental length 

 schaufussi 



8. Antennae with segment eight square, nine and ten transverse; basal 



discal carinae of first tergite one-fourth of the segmental length 



cavifrons 



Antennae with segments eight, nine, and ten transverse; basal discal 

 carinae of first tergite one-third of segmental length 9 



9. Antennae with segments eight and nine very transverse, not much 



