﻿44 PROCEEDINGS OF THE NATIONAL MUSEUIM vol. loo 



METASYRPHUS NEOPERPLEXUS (Curran) 



Figure 10, d-f 



Si/rphus neoperplexus Ccekan, Kansas Univ. Sci. Bull. 15, p. 93, 1Q24. 

 Metasyrphus neoperplexus Fluke, Trans. Wisconsin Acad. Sci. Arts and Letters, 

 vol. 28, p. 101, 1933. 



A series of five males and seven females of this species, all from 

 Matanuska, Alaska, are before me. They are very uniform in appear- 

 ance and are best recognized by the reddish fifth segment in both sexes 

 (a small median basal black dot on the male), small to medium-sized 

 styles on the genitalia, and the arcuated and interrupted spots on the 

 abdomen. 



I misinterpreted this species in 1933. The diffused opalescent stripe 

 on the face of the type male does not appear to be a normal condition. 

 All the specimens from Alaska have a yellow to reddish face and 

 the midstripe is somewhat darkened but never distinctly brown or 

 black. The specimens I reported from Ontario apparently represent 

 another species. The nearest relative of neoperplexus appears to be 

 talus Fluke, but the males can be told readily by the elongate styles on 

 talus. 



The front of the female is shining yellow below the depression with 

 a faint elongate brownish spot above each antenna, shining black above 

 the depression with weak side dust spots ; the ocellar triangle shining 

 black. The mesonotal pile is yellowish ; pleural pile white ; scutellar 

 pile mostly black, some yellow hairs intermixed, especially along the 

 rim. The legs are yellowish to reddish and in fully colored specimens 

 the bases of the femora are somewhat blackish but there is no sharp 

 demarcation of the colors. 



Dr. G. E. Shewell kindly made careful comparisons with the type 

 and while there are some differences in color I believe these Alaskan 

 specimens are neoperplexus. I quote below some of the notes made by 

 Shewell : 



As you have noted in your 1933 paper, the type has the tubercle and oral mar- 

 gin faintly but unmistakably suffused with brownish black. In this, I find your 

 specimen differs. Though there is a very faint suggestion of dark pigmentation 

 below the tubercle, the only area which corresponds closely to the type in this 

 respect is that alongside the facial groove. [Some of the Alaska males are 

 reddish brown on the mid-strip below the tubercle which indicates a variability 

 in this respect.] The color of the facial pile definitely differs. In the type there 

 are no long black hairs below the facial depression and only a few scattered 

 short black hairs on the tubercle. 



In shape and length of genital styles, there is no noticeable difference. 



Attention is called to the mouth edge of the Alaska males, which has 

 a reddish cast somewhat darker than the rest of the face. Also, the 

 abdominal spots on the type are larger, but here again there is consider- 

 able variation. 



