250 NEOTROPICAL PSELAPHIDAE 



Key to the Species 



Pronotum nearly impunctate ; 2.12 mm 2 



Pronotum rugosely and cribrately punctate 3 



2. Antennal segment VIII oblong, much larger than VII ; X shorter than 



IX; intermediate tibiae with an apical spur simplex Male 



Antennal segment VIII only slightly larger than VII ; X larger than 

 IX; intermediate tibiae simple simplex Female 



3. Known only from northern Panama ; 2 mm 4 



Known only from South America south of the Equator 5 



4. Anterior tibiae slightly dilated on internal face for median third of 



length, tapering towards both base and apex; intermediate tibiae 



with an apical spur puncticollis Male 



Anterior and intermediate tibiae simple puncticollis Female 



5. Antennal segments II-VIII longer than wide 



barberi new species, Male 



Antennal segments III and IV wider than long 6 



6. Antennal segment V quadrate, VI quadrate; 2.2 mm. known only 



from Brazil incertus Female 



Antennal segment V slightly transverse, VI quadrate; 2.5 mm. known 

 only from Bolivia 7 



7. Antennal segment XI with internal (mesial) face incised or notched 



at base and toothed at middle dimidiatus Male 



Antennal segment XI simple, ovate with a truncate base 



dimidiatus Female 



Batoctenus barberi new species 



Type Male. Measurements: Head 0.40 x 0.40 mm. including eyes, or 0.167 

 mm. wide not including eyes; cervicum 0.134 mm.; pronotum 0.43 x 0.40 mm.; 

 elytra 0.67 x 0.72 mm.; abdomen 0.60 x 0.53 mm.; tergites in the following 

 proportional length: I (4), II (2), III (iVs), IV (2), V (1); total length 

 2.2 mm.; greatest width is through elytra, 0.72 mm. (PI. XVIII). 



Body very elongate-cylindrical, reddish-brown; head both above and 

 below completely, rugosely, cribrately punctate, the punctures becoming 

 elongate-oval to substrigose between eyes; pronotum both above and laterally, 

 and prosternum completely, rugosely and cribrately punctate save for apical 

 eighth of pronotal disc; elytra subglabrous and shining; abdomen subim- 

 punctate and shining. Pubescence short, sparse and subappressed on head and 

 pronotum; shorter and sparser on elytra; relatively abundant, longer and ap- 

 pressed on abdomen. 



Head much longer than wide if the eyes are not included, with an arcuate, 

 abruptly vertical and glabrous occipital wall; tempora short, oblique and 

 sharp-angled; vertex long, longitudinally convex, simple, extending as a sub- 

 quadrate area apical to eyes. Eyes very large (0.18 mm. long x 0.12 mm. wide 



