240 



UNITED STATES NATIONAL MUSEUM BULLETIN 224 



hypandrium is broad and relatively short, leaving the 

 genital cavity exposed. Female terminalia with spines 

 on the acanthophorites. 



Distribution: Neotropical: Lastaurina ardens 

 Wiedemann (1828). 



Genus Lastaurax Carrera 



Figures 1071, 1080 



Lastaurax Carrera, Arq. Zool. Sao Paulo, vol. 7, art. 1, p. 109, 

 1949. Type of genus: Lastaurax lanei Carrera, 1949, by 

 original designation. 



The following is Carrera's description in translation : 



Head : Face plane in the middle, but salient in the buccal bor- 

 der and in the base of the antenna. Mystax located in the border 

 of the mouth. Front with dense, lateral pile. Ocellar callosity 

 with a tuft of fine bristles. The two segments of the palpus are 

 continuous and not forming an angle at the junction of the two 

 segments. The proboscis is approximately as long as the second 

 and third segments of the antenna combined ; it is sharply 

 pointed at the apex and has a clear, dorsal ridge. The two first 

 segments of the antenna are subequal in length. The third seg- 

 ment is almost two and one-half times as long as the first two 

 segments united ; it has a few cilia in the middle, is linear, and 

 has a subapical concavity. 



Thorax : Pronotum with abundant, lateral pile : mesonotum 

 with developed dorsocentral bristles from the middle of pre- 

 scutum to the prescutellar suture; lateral bristles stout; the 

 pile is more abundant on the sides than in the middle ; scutellum 

 with two long, marginal bristles and some scattered, marginal 

 hairs. Region of the postscutellum with the lateral callosity 

 developed but bare. Pleuron with some hairs in the middle, 

 which on the metapleuron are very long. 



Legs : The legs are slender, with short bristles. The apical 

 spine of the anterior tibia is fine, short and recurved. Claws 

 sharp ; pulvilli developed. 



Wings : First basal cell larger than the second by one-third. 



Abdomen : The abdomen is conical with not very abundant 

 pile, except on the sides of the first tergite where it is more 

 conspicuous. Length 16 or 17 mm. 



Distribution: Neotropical: Lastaurax lanei Carrera 

 (1949). 



Genus Lastauronia Carrera 



Lastauronia Carrera, Arq. Zool. Sao Paulo, vol. 7, p. 104, 1949. 

 Type of genus : Lastauronia travassosi Carrera, 1949, by 

 original designation. 



The following is Carrera's description in translation: 



Head : Face inclined and gradually becoming salient from 

 the top to the bottom ; the superior half is bare, the inferior 

 half has some pilosity which intermixes with the fine bristles 

 of the mystax over the buccal border. Front with abundant, 

 lateral pilosity. The ocellar callosity is salient and has 8 to 

 10 long bristles. The two segments of the palpus are not 

 continuous ; the second segment is inserted in the apex of the 

 first segment forming an angle. Proboscis a little longer than 

 the antenna ; it has a ridge on top and a fine, sharp point and 

 is inclined downward. First segment of antenna a little 

 smaller or shorter than the second ; these two basal segments 

 united are almost half the length of the third segment ; third 

 segment subf usiform. 



Thorax : Prothorax with abundant pile and 2 or 3 pairs of 

 bristles on the lateral lobe; over the pronotum there is a row 

 of long, fine bristles. Mesonotum with lateral bristles and 



with dorsocentral bristles developed ; these dorsocentral bris- 

 tles extend from the anterior border to the posterior border of 

 the mesonotum. Humerus with 6 bristles and some pile. The 

 pile of the mesonotum is more abundant in the margins ; 

 scutellum with 5 marginal bristles, 3 on one side and 2 on 

 the other, mixed with long, fine pile. Postscutellar region 

 bare. Mesopleuron and metapleuron with long pile. 



Legs : Strong. The apical spine of the anterior tibia is very 

 sharp. Claws sharp ; pulvilli developed. 



Wings : First basal cell of wings a little larger than the 

 second. 



Abdomen : With longer, lateral pile on the sides of the first 

 four segments and the pile of the middle of these segments 

 short; the two last segments are considerably more narrow. 



This genus is distinguished from Lastaurus Loew by the form 

 of the palpus and the antenna ; from Lastauropsis Carrera by 

 the form of the mystax; and from the other forms in this 

 complex by the character of the face. Length 16 mm. 



Distribution: Neotropical: Lastauronia travassosi 

 Carrera (1949). 



Genus Lastauropsis Carrera 



Figures 1072, 1081 



Lastauropsis Carrera, Arq. Zool. Sao Paulo, vol. 7, art. 1, p. 

 107, 1949. Type of genus: Lastauropsis villosus Carrera, 

 1949, by original designation. 



The following is Carrera's description in translation : 



Head : Face inclined and gradually salient from the top to 

 the bottom. The lower three-fourths of the face is entirely 

 covered with a dense and uniform pile that extends down over 

 the buccal border where we can distinguish some bristles. 

 Front with abundant, lateral pile. Ocellar callosity salient 

 and with a tuft of long bristles. The two segments of the 

 tarsus are not continuous ; the second segment is attached to 

 the first in such a way as to form an angle. Proboscis larger 

 than the antenna, with a dorsal ridge which is prominent and 

 with the apex pointed. The third segment of the antenna is 

 one and one-half times larger than the two basal segments 

 united ; it is fusiform and the apex is more slender than the 

 remainder of the segment. 



Thorax : Prothorax with abundant bristles and pile. Meso- 

 notum with lateral bristles developed with also a double row 

 of dorsocentral bristles that extend from the top of the hu- 

 merus to the posterior margin. Humeral callosity with 6 large 

 bristles; pile more abundant over all of the margins of the 

 mesonotum. Scutellum with 2 long marginal bristles and some 

 long convergent pile between them. Region of the postscutel- 

 lum bare. Pleuron with long pile on the mesopleuron and 

 metapleuron. 



Legs: Strong with short bristles; apical spine of anterior 

 tibia short and quite sharp. Claws very sharp; pulvilli 

 developed. 



Wings : First basal cell larger than the second by one-fourth. 



Abdomen : Entirely covered with hairs which are very few 

 or scattered on the first segment, but abundant along the 

 sides of the remainder of the abdomen. Male genitalia a little 

 salient, rotate, the lateral aspect situated dorsally. 



This genus is separated from others of the complex by the 

 face being inclined as in Lastaurus Loew, but with a dense 

 tuft of hairs covering entirely the lower three-fourths of face; 

 also the small size of the fusiform third antennal segment 

 as well as the position of the palpal segments, which differ- 

 entiate between Lastaurus and Lastaurax Carrera. Length 21 

 mm. 



Distribution : Neotropical : 

 Carrera (1949). 



Lastauropsis villosus 



